Agrodok 1

Pig keeping in the tropics

Dick Muys
Geert Westenbrink© Agromisa Foundation, Wageningen, 2004.
All rights reserved. No part of this book may be reproduced in any form, by print, photocopy,
microfilm or any other means, without written permission from the publisher.
First edition in English: 1984
Third (revised) edition: 1998
Fourth edition: 2002
Fifth edition: 2004
Authors: Dick Muys, Geert Westenbrink
Editor: Rienke Nieuwenhuis
Illustrator: Barbera Oranje
Design: Janneke Reijnders
Translation: MrS. M. Verheij and R. Corner
Printed by: Digigrafi, Wageningen, The Netherlands
ISBN: 90-77073-53-1
NUGI: 835

Foreword
This revised edition has been made possible thanks to thecontributions by Mr Arie Wingelaar and Mrs Marista da Silva of the
IPC Livestock, the International Training Centre for Animal
Husbandry in Barneveld, the Netherlands.
We also wish to thank the co-workers of Agromisa who havecontributed their time and effort to this Agrodok: Mr Arno Overgraag,
Agromisa's livestock specialist, offered important suggestions andcontributions for improvements to this edition, whilst Barbera Oranje
was responsible for the illustrations and Edwin Nuijten for the lay-out.
Rienke Nieuwenhuis, editor
Wageningen 1998

Foreword

3

Contents
1

Introduction

6

2
2.1
2.2
2.3

Pig keeping systems
Free-range 'scavenging' pig keeping
Semi-intensive pig keeping
Small-scale intensive pig keeping

9
9
12
16

3
3.1
3.2
3.3
3.4
3.5
3.6
3.7

Housing
ClimateTechnical requirements for good housing
Feeding and water troughs
Sizes of pens and runs
Housing the sow and her piglets
Housing fattening pigs
Using liquid manure and dung

19
19
22
26
28
29
31
31

4
4.1
4.2
4.3
4.4
4.5
4.6
4.7

Pig breeding
Managing the sows
Selecting and working the boar
The birth and care of the new-born piglets
Problems related to the birth
Rearing motherless piglets by hand
Looking after and weaning piglets
Record-keeping

33
33
36
38
41
44
46
48

5
5.1
5.2

Fertility disorders
Poor oestrus show in sows
Diseases leading to fertility disorders

53
53
54

6
6.1
6.2
6.3

Pig feeding
Introduction
Nutritional requirements
Sources of energy, protein, minerals and vitamins

56
56
57
58

4

Pig keeping in the tropics

6.4
6.5
6.6

Feeding in practice
Feeding pigs, from weaning onwards
Feeding a sow and her piglets

59
60
62

7
7.1
7.2
7.3
7.4
7.5
7.6
7.7
7.8

Diseases, prevention and control
Prevention by promoting natural resistanceDisease-causing organisms
The use of medicines
Parasitic diseases
Bacterial diseases
Viral diseases
Feed-related diseases
Sunstroke

64
65
66
67
70
72
74
76
76

Further reading

77

Useful addresses

78

Glossary

80

Contents

5

1

Introduction

Pigs and pig keeping in one form or another can be found almost
anywhere in the world. Especially of course in country areas it iscommon for communities to have pigs rooting and roaming freely
around the dwellings, to be brought in one day as household needs
require. Pig keeping enterprises are also to be found in and aroundtowns and cities, and they play an important role in feeding urban
populations.
This Agrodok looks at three typical pig-keeping systems:? Free-range scavenging pig keeping:
A more or less extensive system whose main purpose is toguarantee the household emergency fall-back funds, whilst also
supplying it with a little meat from time to time, without any major
investment of time or money. This domestic scale is very typical ofsmall farmer mixed holdings.
? Semi-intensive pig keeping:A system differing from the above in that the animals are housed
and more attention is paid to their health and feeding. Its aims
remain those of domestic pig keeping, but given a modest amountof inputs, its production is higher.
? Intensive pig keeping:
Which aims at producing meat for the market efficiently andprofitably, usually with larger numbers of pigs. This type of system
requires significant inputs of time and money, with careful
calculation of the costs and the resulting benefits.
We will consider the main characteristics of each of these systems, thepurposes they serve, and the methods employed, as well as noting
their limits and the ways of improving them. There are of course any
number of systems in pig keeping. The three models we describe givean idea of the options available and the developments possible to6

Pig keeping in the tropics

make the transition from extensive to intensive management, with thepoints to watch out for.
This book is particularly written for those who may find themselvesadvising farmers involved in pig keeping. This does not mean thatthose who wish themselves to set up or make changes to an existing
system will not profit from the information provided.
Anyone who is considering keeping pigs, or improving an existing
system, must before anything else be clear about the situation on the
ground, the resources available and the constraints, in order to decideon the type of system to introduce in practice.
Advisors will first try to identify the resources available to improve asystem’s productivity, working initially on the basis of a small numberof animals and the means of production available locally. If this is
successful, and there is sufficient demand, the system can be
developed further. It must nevertheless be borne in mind thatgenuinely intensive pig farming requires major investment, and that
there are great risks if such investment is not backed up with thenecessary experience and technical knowledge.
It is therefore all the more important for farmers inexperienced but
interested in this domain to establish their base progressively. They
would be best advised starting up with a semi-intensive approach,concentrating above all on establishing good housing and proper
feeding routines for a small group of healthy animals, taking proper
advantage of all locally available resources.
Agrodok summary
The three systems of pig keeping are presented in Chapter 2, with thevarious possibilities for improvement.

Chapter 3 looks at housing: why is this such an important element in
the system, and what makes for good pig housing? It outlines thevarious parts of a piggery and deals with the installations required forfeeding and farrowing. It also considers the housing requirements ofthe sow and her piglets, and of the fatteners.

Introduction

7

Chapter 4 turns to the question of animal management, covering themanagement of the mother sows and the boar(s), the birth of thepiglets and potential problems, the care of the piglets (including teethtrimming and castration), and finally the important question ofmanagement records.
Chapter 5 takes a brief look at oestrus show and fertility disorders,
whilst feeding is the main preoccupation of Chapter 6 - nutritional
requirements, how to meet them, practical aspects or feeding and thefeeding of sows nursing a litter.
Finally Chapter 7 concerns the main diseases that may unfortunately
be encountered. Preventive measures are detailed, and a number ofgeneral remarks on the use of medicines are made. The symptoms ofthe diseases are described and indications are given of the treatment
possible.

8

Pig keeping in the tropics

2

Pig keeping systems

2.1

Free-range 'scavenging' pig keeping

Figure 1: Free-range pig keeping (after Holnes, 1991).
Main characteristics
The main characteristic of this system is that the pigs move freely
around the house and surroundings, scavenging and finding forthemselves a large part of their food. Often the food they collect is
supplemented with kitchen refuse or agricultural waste products.
Few or no arrangements are made to provide the pigs with shelter, andno money is invested in quality food or medical services.
Local breeds are commonly used, since they are more tolerant of lowquality feed and have a higher resistance to diseases. In general there
is no attempt to improve production by selective breeding or any othermeans.
In some cases the pigs are not bred on the farm: piglets are brought inand are fattened during a season when food is plentiful, for sale at alater date.
Production goals
In most cases the pigs are not kept to provide meat for the household,nor as a regular source of cash income (if there is any cash income thiscomes from other activities). The importance of scavenging pigs is

Pig keeping systems

9rather as a ‘savings account’ or ‘insurance policy’ i.e. they are only
sold when extra cash is needed (e.g. for buying seeds or fertiliser, attimes of illness or family festivity, to pay school fees, to make up for alost harvest etc.). In this way loans (with the associated problems ofhigh interest rates and repayment) can be avoided.
Pigs can also play a specific role in social life, when at weddings andother festivities they are presented as gifts or offered as food.
Socio-economic aspects
Traditionally pigs are often owned or kept by women (and/or
children), with the result that any financial benefits usually go towards
the needs of the household. It also has the effect of strengthening thewomen’s economic position.
Keeping scavenging pigs requires a minimum amount of inputs. The
financial risks involved in this system are small, with little money
being invested and little time spent looking after the pigs.
Potential for improvement
The main constraints with scavenging pigs are the high rates of piglet
loss, and slow growth rates. Pigs kept in a free-range system will not
grow quickly, because they expend a lot of energy in their scavenging
activities. Worm infestation is also an important problem resulting inslower growth rates.

? Enclosing the pigs
Enclosing your animals can lead to improved management. Keeping
pigs together by fencing a piece of land may be difficult to
introduce, but it is the first thing to do if you are aiming to bring
piglet death rates down, reduce the energy lost in scavenging, andimprove the health and growth rates of your pigs. To make a fence,strong wire netting is ideal, but you can also use local materials
such as bamboo, thorny shrubs, tree trunks etc. The fence must be
sufficiently dense that even the small piglets cannot escape.
Shade is essential. If there are no trees or other source of shade asmall shelter must be provided (Figure 1). The animals can also

10

Pig keeping in the tropics

shelter there when it rains heavily. The structure can be as simple asfour solid tree trunks with a roof on top.
Further improvements can be made by separating the animals into
different groups according to their final purpose. Animals forfattening and not for breeding should be kept enclosed. For theseanimals rapid growth is important. By caring for them well, in asmall clean pen if possible, higher growth rates are possible than foranimals left to roam outside. Most of the breeding stock however
can be left outside. The pregnant sows should be separated from theothers just before farrowing and brought inside to deliver. With
proper housing a greater number of piglets will thrive.
? Feeding the pigs
Providing scavenging pigs with extra feed will improve their
growth. Root crops and almost any village refuse can be fed . If thepigs are enclosed, part of the land can be used for growing green
fodder. At the same time there must always be an adequate supplyof fresh drinking water available for them.
? Prevention of worms
Parasites pose a serious problem when keeping pigs outside, as thewet tropics provide ideal conditions for them. Worms are the mostcommon parasites. A pig infected with worms will be in poor healthand will grow very slowly. If the pigs are kept in an enclosure,measures must be taken to control the levels of worm infestation.
This is explained in the next section (2.2).

Pig keeping systems

11

2.2

Semi-intensive pig keeping

Figure 2: Semi-intensive pig keeping (after Holnes, 1991).
Main characteristics
In semi-intensive systems pigs are confined to a limited space. Thismeans that that they cannot gather their own food and are completelydependent upon their keeper. Once or twice a day fresh water andfodder (usually kitchen refuse or agricultural waste) have to bebrought to the pigs. This system of pig keeping opens up possibilities
for improved feed and disease control, which in turn can result infaster growing and healthier pigs and/or in larger litters.

Apart from the economic reasons there are also some very practicalreasons for keeping the animals tethered or enclosed. It prevents crops
from being damaged by the pigs for example, and it reduces the risk ofthe pigs being stolen.
Although this system of pig keeping demands only low financial
inputs, more time and effort needs to be spent on the pigs. Moretechnical knowledge is also required.
Production goals
In general the creation of a ‘savings account’ or ‘insurance policy’
remains the most important strategy underlying this form of pig
12

Pig keeping in the tropics

keeping. Nevertheless in areas close to urban centres or on maintraffic routes for example, where it is possible to sell pigs moreregularly, small-holders (often women) will have intensified their pig
keeping by adopting the semi-intensive approach.
Socio-economic aspects
The introduction of a commercial approach may have an impact on thebalance of income earned within a family. The result is often to thedetriment of the women and children. For if, traditionally, women
were involved in pig keeping, it is often the men who get involved
when the pigs become commercially interesting. This comes aboutbecause the extension services are often reluctant to work withwomen, and because the women themselves are often obliged to makeapplications to or through their menfolk for access to credit or land, orfor help with construction work or farm-related book-keeping. This
process leaves women less able to decide for themselves what will bedone with the animals and the cash income earned; this reduces their
independence.
Potential for improvement
Improvements to semi-intensive systems are made by focusing
attention on feeding and health care practices, and by selective
breeding.

? FeedingA first and simple step can be taken by making sure that theavailable feedstuff is properly distributed. It is important that thebest of the feedstuff be given to the pregnant and the nursing sows
(who supply your future breeding stock), and also to the piglets thathave just been weaned so that they get off to a good start in life.
A further improvement to be made is to raise the quality of the feedby adding to the basic ration. For this see Chapter 6, which deals
with feeding issues. If additional feed has to be bought in, you
should first consider whether the advantages really justify the cost.
This will depend on several factors, such as the quality of your meat

Pig keeping systems

13and the price you finally obtain for it, and the total cost of bringing
in and storing the feed.
? Breeding
A farmer can improve the quality of new stock by choosing theright animals to breed from (selective breeding). If nursing sowsand their piglets are kept separate from the others, it will be easierto select the stronger piglets for breeding. The remaining piglets canbe fattened for sale or for slaughter.
Once you have started separating out the best sows for breeding(see Paragraph 4.1), giving them good housing and proper attention,
you have taken the essential steps towards improved breedingpractice. And once this is achieved it could be worthwhile investingin a good boar to produce strong healthy litters. Buying a boar is aserious investment, as it involves a number of costs - travelling insearch of a good animal, transport costs, purchase price... The costs
can only be recovered if conditions on the farm allow.
The purchase of a boar is a project that a group of farmers may wish
to undertake together. It is also very useful to exchange boars
between neighbouring villages, in order to avoid the problems of inbreeding.
This level of management however demands more knowledge,
experience and time, in the keeping of records for example orroutine checks for heat etc. See Chapter 4 for more information on
improving breeding.
? Prevention of worms
We mentioned above the problem of worm infestation in outdoor
pigs. In fact the adult worms live and develop inside the pig, laying
eggs which are excreted with the faeces onto the soil. Given theright temperature and humidity, larvae emerge from the eggs andwill probably be eaten again by the grazing pig. These larvae caneven penetrate into and cross the animal’s skin. Once inside the pig,
they grow into mature worms again and the cycle can start again.

14

Pig keeping in the tropics

The eggs and the larvae in the soil can die out after a while if
sufficient time passes for them to dry out under the sun. As a resultof this the risk of serious parasite build-up in the field can be
reduced by regularly changing the grazing area. If possible theanimals should be given a fresh piece of ground about every 14
days. In dry periods the animals can stay longer in the same field
because the worms do not develop so quickly.
After a period of grazing the field should be left empty for a while
to allow the larvae to die. In the wet season it is better to leave afield for about 2.5 to 3 months before re-using it; in the dry season
when the larvae and eggs die more quickly, the field can be usedagain after 2 months. With this system, changing the enclosure
every two weeks requires at least four different fields, which is
expensive. If there is a shortage of land, in some areas a simple
pigsty can be made to keep the pigs in during the wet season. By
letting the pigs out in the dry season only, less land will be required.
Animals kept outside will always be slightly contaminated withworms. Some infestation in older animals is not serious, as theseanimals usually have some natural resistance. Young piglets
however are very vulnerable. To prevent young piglets from being
infected directly after birth, the breeding sows should be wormed
about 1 week before delivery (treatment which drives out all theworms). After worming, the sows should be washed to ensure that
there are no worm eggs clinging to them. They should then be kept
inside for delivery.
To prevent re-contamination, the pen should be properly cleaned
every day. All this being done, the young piglets stand a goodchance of being born into a worm-free environment. See Paragraph
7.4 for more information on this.
? Use of pig manure
It is a good idea to use the pig fields occasionally for crops, as thesoil will have been fertilised by the pig manure. This will also cleanout the parasites and after a year’s cropping the soil should becompletely clear again.

Pig keeping systems

15

2.3

Small-scale intensive pig keeping

Figure 3: Small-scale intensive pig keeping (after Holnes, 1991).
Main characteristics
The main characteristics of an intensive pig keeping system is thatpigs are kept in complete confinement. Buildings are provided to keep
fatteners, boars, sows, and sows with their litters separate. In thissystem housing amounts to much more than providing a simple
shelter. Larger numbers of pigs may be kept and the pigs must be wellmanaged because commercial commitments have been made. Knowhow is required to make the right decisions at the right time. The
following chapters in this book provide a lot of this know-how,because they concentrate on the management of small-scale intensive
pig keeping.

High investments are required to provide improved buildings, and tobuy in feeds and medicines. These are especially necessary if thechange towards improved breeds is made.
In this system of pig keeping, kitchen refuse and agricultural waste
products will generally not be sufficient to feed the animals, so certain
feeds will have to be bought. Buying in extra feed to help the pig growfaster only makes sense if the animal can be marketed earlier than

16

Pig keeping in the tropics

usual or if heavier animals can be sold, thus earning much higher
prices.
Local breeds are often considered to be a cause of low productivity(small litter sizes and slow growth rates). In general, however, thesebreeds are very well adapted to the local circumstances. Although‘improved’ breeds have great potential they make high demands on
feed quality and careful husbandry.
Intensive systems are aimed to provide a major source of income for agroup or household. The animals no longer function as a savings
account but are grown to be marketed. This means that regular accessto the market is needed, which might imply dependence on a
middleman.
Potential for improvement
The improvement of small-scale intensive systems needs specialised
know-how. Progress can be achieved particularly by paying attention
to the animals’ health and conditions. The stability of the project
depends on a new approach to production, as the farmer has to be
thinking more and more in terms of the market.

? Marketing
To render the unit economically viable a completely different
approach to keeping pigs is necessary. The animals have to bebrought to market when conditions (prices, the pigs’ condition etc.)
are right. A strategy for optimum buying and selling has to be
developed, taking into account the importance of regular transportand dependable sales outlets.
If there are problems or a catastrophe with the pigs (disease or
accident for example), an extra financial input will have to beavailable to keep the unit in operation. This is not typical in
traditional pig keeping.
? Technical knowledge
A local extension service is important as a source of support andtechnical advice. Veterinary services should also be available whenrequired.

Pig keeping systems

17

To be able to manage the business correctly proper detailed records
must be kept (see Paragraph 4.7).
? Disease control
If too many pigs are confined together there is a high risk ofinfection spreading quickly among the animals. For most diseases
and infections the organisms causing the disease (bacteria, wormsetc.) are found naturally in the animal’s environment. A lot of
locally bred pigs are infected but have enough natural resistance tostay alive and even to develop. This natural equilibrium canhowever very easily be disturbed, with the result that the pigs
sicken or die. This can be due to changes in the season (in the wet
season, parasites are often present in larger numbers), feed
shortages (which weaken the animals) or changes in pig keeping
routines.
Preventive measures aim at increasing the animals’ resistance (forexample by improving the quality of the feed) and they aim at
reducing the sources of infection, e.g. by keeping a smaller numberof animals in the same area or by improved hygiene (providing dry
and clean housing, regularly moving the pens etc.). When large
numbers of pigs are kept together medicines are sometimes
necessary to prevent disease outbreaks. The most essential andpowerful tool to combat disease however remains good hygiene.
By ensuring that the pen is always kept clean the chances ofinfection remain small, and a healthy pig will grow faster than an
animal infected with disease. See Chapter 7 for the prevention andcontrol of diseases.

18

Pig keeping in the tropics

3

Housing

Figure 4: Pig house (Barbera Oranje).

In the preceding chapter we indicated that improved housing is an
essential factor in the conversion to commercial pig keeping.
There are numerous advantages to keeping pigs inside:? The animals spend their energy putting on body weight rather thanon seeking food and shelter.
? The number of piglets surviving will rise if they are born in secureand healthy surroundings.
? Controlling the health of the pigs is easier if they are housed, since
it is easier to maintain good hygiene.
? Feeding routines can be more carefully controlled.
? Manure can be easily collected and used for fertilising land.
In this chapter the necessity for, and the technical aspects of proper
pig housing are explained.

3.1

Climate

The climate to which a pig is exposed is very important. If a pig ishoused this can be controlled to a certain extent. Pigs are very
sensitive to sudden changes in temperature. They cannot stand heavy
Housing19

rain or drought. Strong sunlight is bad for them, as it causes their skin
to dry out. Albino pigs especially cannot endure the sun because they
have no pigment in the skin and they soon burn. This illustrates thenecessity for shade. Pigs kept for optimal production should therefore
be protected from climatic stress. This is only possible by ensuringthat the animals are well housed.
The most important factor to consider in organising proper housing istemperature. A pig’s body temperature can vary with the temperatureof its surroundings and a steady body temperature is important for aproper growth rate.

Figure 5: Protection against climatic influences.
Body temperature
Every living animal produces heat, when converting its food for therequirements of growth. The more an animal eats, the faster it
grows.... and the more heat it produces. Heat is also released when an
animal is active (for example, when walking).
Warm-blooded animals (birds and mammals) can make use of some ofthis heat to keep their body temperature level. The normal internal
body temperature of a pig is about 38.5°C. A healthy animal willautomatically try to maintain this temperature. Any great deviationfrom this norm may lead to the animal’s death, because all of its bodyprocesses are geared to work at this temperature.
20

Pig keeping in the tropics

A sick animal’s temperature may rise to above 40°C if its temperatureregulating mechanism is disturbed. If a pig’s temperature rises above
41°C it will die. The same applies if the temperature drops too much.
Especially in the tropics animals generally produce more heat thanthey need to maintain their body at an ideal temperature. To avoid
overheating they have to get rid of any superfluous heat in one way or
the other.
Controlling body temperature
One way of dissipating heat is to give off moisture by evaporation ‘sweating’ is an example of this process. Pigs however do not havesweat glands and are therefore unable to do this.

Releasing heat by evaporating water from the skin is also possible if
there are puddles and pools that the animals can lie and roll in.
Moisture evaporates from the wet skin, releasing excess heat from thebody. If the water is cooler than the body the body heat will betransmitted to the cooler surroundings. It cannot do any harm,
therefore, to provide the animals with a pool of water, as long as thewater is clean and not a health hazard. Pools are very important for
improved breeds kept enclosed but are less important for indigenous(local) breeds. Good ventilation is also essential.
Evaporation can also take place through the mouth, and in very hot
weather pigs can often be seen panting. This is because, by breathing
more quickly, more air is exhaled through the mouth and other air
channels, and in this way more water is evaporated.
If the animal is unable to get rid of excess heat in one way or anotherit will try to reduce its body temperature by producing less heat, that is
to say, by eating less and therefore not growing so quickly. If it feels
cold it will try to prevent further cooling by generating more heat, forexample by exercising its muscles (shivering). This will use up its
energy and its growth rate will fall.

Housing21

The hide of an animal protects it from the outside world. One of its
protective functions is to help regulate temperature changes, for it
serves as an insulating layer between the internal organs and theoutside. A cow has a very hairy coat, which is one of the ways it
protects itself against the cold. A pig does not have much of an
insulating layer of hair (or fur), but it can form a layer of fat
underneath its skin.
Young piglets do not yet have such a layer to protect them, so in thefirst few days after birth temperature-regulating mechanisms do not
function well. It is therefore important to ensure that the surroundings
are sufficiently warm for the piglets. As the piglets get older they willneed less heat.
Ideal temperatures for pigs
The temperature at which optimum growth and food conversion isachieved differs with the weight of the pig:

? piglets one day old? piglets up to one week old? piglets up to about 8 weeks old? animals up to 90 kg in weight

3.2

35°C
30°C
20°C - 28°C
18°C - 22°C (or a little cooler)

Technical requirements for good housing

The construction of pig pens and houses will depend to a certain
extent upon the climate and local circumstances (e.g. numbers of pigs
to be kept). Local conditions are also important, in terms, for example,of the construction site (waterlogged, exposed to wind...etc.) or thebuilding materials and the skills available for the construction of theinstallations.
In hot, humid, or damp areas, breeze and shade are important factors.
The buildings should be as open and airy as possible. The walls of thepens should be so constructed that the wind can pass freely throughfor good ventilation. In some areas animals should be protected22

Pig keeping in the tropics

against periodic temperature drops by ensuring that any heat can beretained.
A few important requisites for the pen are:? It should not be draughty.
? Bright sunshine and heavy rain should not be able to enter.
? There should be no great variation in temperature inside the pens.
? They should be easy to clean.
? Provision should be made for storing the manure, litter and run-off
for later use.
A pen satisfying these requirements will make a major contribution to
the good health of the herd, counting towards lower piglet mortality,
faster growth and increased feeding efficiency. The most suitablehousing for less intensive holdings in tropical regions consists of awalled and roofed pen with a yard or run (see Figure 6). Bedding
material should be provided in the covered pen and the run should
contain a trough and if possible sufficient space for a large water tank.

Figure 6: Pen adapted to a tropical climate.

When building a pen, care must be taken in choosing the site. In hot
areas the site would benefit from the shade of a group of trees, as trees
Housing23

absorb and screen a good deal of heat. The pen should be near a watersupply, so that water is readily available for the animals, and it mustbe easily cleaned.
The roof
The first essential is a roof, which can be made of various materials.
The most practical approach is to use the same material as is used forthe local roofing. A roof of leaves is a good insulator against heat andcold, but it has the disadvantage of rotting quickly. Corrugated iron or
aluminium sheets covered with leaves would last longer but are more
expensive. Other materials can be used, provided that they protect
against rain and sun, heat and cold. If possible the roof should beconstructed with its longest slope against the prevailing wind and rain.
If an opening has been left between the walls and the roof (seeParagraph 3.5) there should be sufficient outside overhang to preventthe rain entering.
The floors and bedding
The floor of the pen should be slightly raised above its surroundings to
avoid puddling or flooding in wet weather. It is also advisable to slope
the floor slightly, so that the pen is situated at a higher level than therun. This will allow the liquid manure to run off more easily. If a drain
is fixed at the lowest part of the run the run-off and manure can becollected into a pit. Pig manure is a good fertiliser so it is important tocollect it (see Paragraph 3.6).

The floor can be of compacted soil or loam; it should be kept hard andsmooth so that it can be easily swept clean. The pigs can be ringed tostop them rooting in the soil. In Europe special pig rings (small piecesof iron) are sold, which are pinched into the upper part of the nose(snout) with a special tool. Wooden floors are not advisable because
the crevices make them difficult to keep clean, and the pigs bite into
them. Wood will rot when damp.
If cement is available a concrete floor is a possibility. The concreteshould not be so rough that the animals can scratch themselves on it. A

24

Pig keeping in the tropics

floor that is too smooth is also dangerous, as the animals may slip anddo themselves serious injury. To improve a floor that is either too
rough or too smooth a few shovels of soil can be thrown into the pen
every day after cleaning. This is not only a precaution against
accidents, but it is also healthy, as the animals can take up valuable
minerals from the soil (iron for example).
The disadvantage with concrete is that it is a bad insulator. In hot
weather the animals can take advantage of this by lying on the cold
concrete to cool themselves down, but in cold weather too much bodyheat will be lost and the younger animals will get too cold. In young
animals this increases the risk of diseases like pneumonia for example.
The coldness of the concrete can be reduced by seeing that the animals
have bedding material in the pen. For young piglets put a cloth on thefloor. For older pigs various materials can be used, such as rice straw,
sawdust, dry leaves etc. As a precaution it is better not to use plants orseeds that may be poisonous. Pigs have a habit of finely chewing their
bedding litter and will swallow part of it. This will not do any harm aslong as the animal does not eat harmful plants. The leaves of the
Wonder Oil Plant (Ricinus communis) for example should not be
used. Its seeds are poisonous and could get amongst the leaves.
Bedding material should be changed regularly to keep the pen clean
and to avoid any parasite build-up. The mixture of bedding with dungand urine makes an excellent fertiliser for the fields, and is especiallyvaluable if specially stored for transformation into compost.
The walls
The construction of the walls depends again on the climate. In thetropics they should be left as open as possible for good ventilation. A
low wall approximately 1 metre in height will suffice, with an opening
between the wall and the roof. In windy areas, the roof (or ceiling)should not be too high, otherwise the pen will cool down too quickly
in the strong winds. Completely open walls, made of wire netting forexample, are seldom recommended, as pigs always like to shelter fromwind and rain. In higher and colder areas the walls should beconstructed in such a way that it is possible to close the walls of the

Housing25

pen completely. In the daytime, when temperatures are higher, the top
section of the walls can be opened, to be closed again towards evening
to keep the warmth in. It should be possible completely to close theside exposed to the rain.
If the walls are made using traditional mud and wood techniques aprotective row of hard wooden poles should line the inside. This will
prevent the pig from digging into the earthen wall.
The walls can also be made of boards or bamboo poles. A row ofsmall tree trunks will provide a simple wall, even if the wind can enter
more or less freely, as long as part of it is closed with woodwork toallow a space for the animal to shelter.
Cement walls will be the most expensive but they are stronger and last
longer. If the supply of cement is limited, it should be used in priority
for the floor.

3.3

Feeding and water troughs

Feeding should be done outside if possible. The feed trough can bemade of cement, iron, or hardwood. The trough should be long enoughfor all the animals in the pen to feed from it at the same time.

Figure 7: Separate feeding for pigs (from: Udo, 1985).

26

Pig keeping in the tropics

Animals of different sizes, older and young sows for instance, should
not be kept in the same enclosure. It may happen that weaker animals
are bitten and do not get enough to eat when feeding. The stronger
animals will fatten at the expense of the others.
If for one reason or another animals of different age and size have to
be kept together, precautions should be taken to ensure that they do
not get in each other’s way when feeding. This is possible by giving
each animal or group of animals a separate feeding space, byenclosing them inside railed-off sections (see Figure 7). These sections
will have to be closed from behind and can be of metal or wood(although wood wears out more quickly).
In very hot areas a water bath should be provided in the run for the
animals to cool down in (see Figure 8). The bath should not be too
deep: for older sows about 20 cm deep, for younger animals the waterlevel can be adjusted accordingly. Care should be taken to prevent the
young piglets from drowning.

Figure 8: Water bath in a run (after Eusebio, 1987).

The bath should be cleaned out regularly to prevent the developmentof parasites and diseases. Cement is the most suitable construction
material, since a pit dug in the soil will quickly develop into an unmanageable mud bath.
Housing27

3.4

Sizes of pens and runs

In Figures 9A and 9B an enclosure is shown suitable for all types ofpig. If there is a run, the animals will get into the habit of goingoutside to excrete. This can be encouraged by ensuring that thecovered pen is not too big. Provided that the doorway is wide enough,the inside area of the pen need not be very large.

Figure 9: Pen and run for all types of pigs (A:side view; B:tot view)

A pen measuring 2 x 2.5 metres is adequate for a sow with a litter ofpiglets. If there is no run however, the sow and piglets will need anarea of about 3 x 3 metres. The run should be 3 x 5 metres in size. It

28

Pig keeping in the tropics

should be larger if a water bath is installed and it must be well fenced,
to make sure that the piglets do not escape. These dimensions are also
suitable for housing 12 - 15 weaned piglets, or 10 fattening pigs, or 3
breeding pigs.
The pen in Figures 9A and 9B is suitable for all types of pig. It is agood idea to put the piglets in a separate corner where they can feedon their own away from the sow (see next Paragraph).

3.5

Housing the sow and her piglets

As we have stated, young animals should be protected from cold
directly after birth. Plentiful quantities of good dry bedding should beavailable to keep the piglets warm. If this does not suffice and you
have the means, a heating lamp should be installed in a separate cornerof the pen for the first few weeks.
The piglets should, if possible, be given a secure place of their own inthe sow’s pen, but at a small distance from her. This is because there isalways the risk that the sow accidentally kills her piglets by lying
heavily on them. To make it impossible for the sow to crush her
piglets against the walls, inside the pen a horizontal rail should beinstalled parallel to each wall, 15 to 20 cm away from the walls and ata height of 15 to 20 cm from the floor.
Farrowing crate
Another solution to prevent piglets being crushed during and after
birth is to use a farrowing crate, a sort of cage confining the sow andlimiting her movement. The crate takes up a floor area of about 65 x
220 cm, and resembles a cage made of iron or wooden bars. There aredoors at the front and back of the crate. Bars across the top prevent thesow from climbing out. The crate is installed in the pen and just next
to it a warm spot is provided for the piglets, who thus remain in close
contact with the mother but can move freely about and away from her
as they please.

Housing29

The dimensions of the farrowing crate depend on the average size ofthe sows. For smaller types the crate should measure about 50 x 150
cm, and for the larger commercial breeds 65 x 220 cm.
Piglet boxes
Figure 10 illustrates a ‘piglet-box’. This is a farrowing crate combinedwith a special ‘creep’ area where the piglets are kept warm. The box
allows the piglets to crawl away from the sow to a bedded area on
either side of her. After a few days the extra shutters can be removed,
so that the piglets can run freely about the pen. This system has
proved very successful; the piglets nearly always prefer the protective‘creep’ rather than lying against the sow. The sow should be kept in
the farrowing crate for about two weeks after farrowing.

Figure 10: Farrowing crate with covered ‘creep’ area for piglets(from: Udo, 1985).

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Pig keeping in the tropics

Before using the crate for the next sow it should be thoroughly
cleaned. When the sow leaves the crate a warm place should be found
for the piglets. This could be in a separate corner of the pen, where
they can be introduced to a little feed. When the piglets reach a weightof 8 - 12 kg they can be weaned, that is to say, separated from the sow.

3.6

Housing fattening pigs

Pens to be used for fattening pigs are less demanding. There should be
no more than 10 fattening pigs in one pen, and a simple pen with a run
will suffice (Figure 9). This also applies to the breeding animals andboars.
The breeding sows and boar can be allowed out on a fenced piece ofland occasionally, as this is very good for their general condition.
Their leg muscles will benefit and in rooting around they will findsome of the essential elements that are sometimes lacking in the feed.
This is more important for the breeding herd than for the fatteners; afattener will never get old (slaughter) but a good breeding pig will be
used for as long as possible.
The danger of parasite infection must be taken into account however
when putting the animals out (see paragraph 7.4).

3.7

Using liquid manure and dungPig urine and dung are good fertiliser for the land, so it is wise to
make good use of them. Before using the dung it is best to let it
decompose first by heaping it separately. Pigs enjoy chewing theirlitter and playing with it, so it is good to give them plenty of any kindof organic matter for this purpose. If they feel happy, their condition isbetter anyway, and the manure will be better too! Once the litter fromthe pens has been broken down by the pigs it should be left to rot for awhile (in the shade), by being kept moist and turned occasionally, toapproach compost quality.
Pig keeping can be combined with on-farm fish culture:- apart frombeing put on the land, the pig manure can be used to fertilise the

Housing31

fishpond. The manure, or some of the rich run-off from the pens (nottoo much), will stimulate the growth of natural fishfood and water
plants. This increases the food available for the fish who in turn growfaster. In addition, water plants such as Ipomoea reptans growing on
the surface of the water grow more rapidly and provide excellent
green fodder for pigs.
For further information on this combination see Agrodok No. 21, ‘Onfarm fish culture’.

32

Pig keeping in the tropics

4

Pig breeding

4.1

Managing the sows

Sows that are to be kept for breeding should be selected and separated
from the litter at about 3 months of age. They should not be allowed to
get too fat because this will create fertility problems. They should get
a little exercise to remain in good condition.
Young sows are mature enough to conceive at about six months ofage. They should not be served (mated) too early however as it isbetter to wait until they are fully grown. If they are well fed andhealthy this will usually be at about eight or nine months. Mating too
early will result in small litters, problems at birth, a loss of conditionand poor growth of the sow.
Mating can only be successful during the sow’s period ‘on heat’(‘oestrus’). Sexually mature, non-pregnant and non-lactating sowscome on heat for two or three days about every three weeks. However
if the boar is kept separate from the sows and gilts (young sows, notyet mated), as he should be, it may sometimes be difficult (butnevertheless essential) to recognise the heat (see below).
Selecting sows for breeding
When selecting the sows to be kept for breeding, the following points
should be considered:? They should have at least 12 normal teats.
? They should be the biggest and heaviest of the litter.
? They should have strong legs and walk well.
? Their parents should be good breeding animals capable ofproducing good litters at regular intervals.
Recognising the heat
Twice a day (in the morning and in the evening), a check should bemade of the sow’s oestrus condition. This should be done some timeafter feeding, preferably in the morning. Doubtful cases can be lookedat again in the afternoon. Differences in breed and climatic variationsin the tropics sometimes make it difficult to recognise oestrus. The

Pig breeding33

first sign is a redness and swelling of the vulva, which is more obvious
in gilts than in sows. Another sign is that other sows in the pen start tomount the sow on heat.
The clearest indication is the reaction of
the sow to the boar. If a boar is brought
alongside the sow’s pen, a sow on heat
will advance towards the boar. They
exhibit a typical ear display (especially
noticeable in breeds with erect ears). If thesow does not react convincingly, then theboar should be let into the pen. The boar
will nose the vulva and prod the sow in the
belly and flank. If the sow accepts he will
mount her. A good oestrus sow will standrigid when mounted, with her back legsslightly apart (the so-called standingreflex).
Even without a boar, the standing reflex
can be provoked in a good oestrus sow,although it is less easy with gilts. You
should approach the sow quietly and prod
her gently in the flank with your fist. Then Figure 11: The standing
press down gently with both hands on her reflex
back. If the sow allows this you can try tostraddle the small of her back (see Figure 11). If the animal does not
move from her position she is almost certainly on heat.
Gilts coming on heat for their first time should not be served
immediately. They are still too young and their bodies are not yetstrong enough to carry and deliver a good litter. Gilts in goodcondition can be served for the first time after they have come on heat
regularly a few times (keep records! see Paragraph 4.7). Let a young
boar who is not too heavy do the job as gilts are too small for a heavy
boar.

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Pig keeping in the tropics

Timing the service
In normal circumstances healthy sows and sufficiently mature gilts
should be mated regularly (food supply and sows’ condition
permitting). Once a sow has farrowed she will not usually come onheat for some time (whilst she is still feeding the piglets). Most sowscome on heat again in the week after weaning their litter. When they
finally do, they are very fertile and should be served. They are full ofenergy and will conceive easily. The second heat is not as strong andthe instinct to conceive will have decreased a lot. At the third heat asow may not conceive at all and you might be left with a pig only
good for slaughter. On top of that, if a heat passes without service, theanimal has to be fed for a further three weeks until the next heat,without being productive.

Sows should not be served by the boar at the very beginning of theirperiod on heat, nor at the end; this will result in small litters. There isan optimum period during the three-day heat for service. On intensive
holdings, a sow is usually served 12 to 24 hours after the standingreflex has been provoked (without the boar). The standing reflex
occurs when she is at the most fertile moment of her heat and it
indicates the moment when she is most willing to accept the boar. One
should always make sure that it is the first standing reflex of the heat,and this is only possible by regular thorough checking.
In very hot conditions especially the period of fertility is shorter andless obvious. If there is any doubt about the best moment, or if theheat was only detected after introducing the boar, it would be better tomate them twice after noticing the oestrus - preferably at the end of
the first day and at the beginning of the second. If the heat is really
doubtful then it would be better to postpone mating until the next heat.
Mating can take quite a long time, varying between 5 to 20 minutes.
The animals should not be disturbed during the operation, but it isadvisable to keep an eye on them. Heavy boars should not be used onlighter sows. Often a young boar is kept for the gilts and an older boar
for the heavier sows.

Pig breeding35

Three weeks after mating, the oestrus should be extra carefully
checked. If there is no sign of it then the sow is usually in-pig(pregnant).
Feeding
In the weeks before mating gilts and sows should be well fed (proteinrich feed), as they must be fit and strong for mating. With good
feeding the chances of producing a large litter increase.

In reality a sow feeding a litter is already being fed a protein-richration (see Paragraphs 6.5 and 6.6) and this should be continued until
she has been served. After mating the ration can be reduced to thenormal protein requirement (13 % - see Paragraph 6.5).
Later, in the final few weeks after pregnancy, she will need proteinrich food again, because the next litter of piglets will be developing
fast inside her.

4.2

Selecting and working the boar

Selecting the boar
Selecting a boar is even more important than choosing your breedingsows. In choosing a breeding boar, the same factors should be taken
into account as for the sows; this includes the presence of 12 nipples.
Avoid choosing a boar too highly in-bred from your existing stock, as
in-breeding will lead to reduced fertility, poor growth, and lower
levels of disease resistance.
Managing the boar
Young, healthy and well-developed boars should be mated for the firsttime when they are 8 to 10 months old. Their first sow should be of
their own size or smaller. In the early stages the young boar should notserve more than 1 sow per week. The number of services cangradually be increased as indicated in table 1. If a boar mates more
often than this, his health and productivity will suffer.

36

Pig keeping in the tropics

In hotter climates a single boar will suffice to serve between 5 and amaximum of 25 sows. It is nevertheless advisable to keep at least 2boars, an older heavier boar for the bigger sows and a younger lighter
one for the gilts. A boar should function well until about 5 to 6 years
old. Once he gets older than this the younger boar should take hisplace and a new young boar be selected, or brought in, for the youngsows.
Table 1: Number of services of a boar in relation to its age.
Age of the boar
8 - 10 months

Services
Once per week

18 months

Max. 3 times perweek
4 - 5 times perweek

24 months orolder

At this stage you should check that the boar servesproperly and that the sows served by him aresuccesfully inseminated.

Boars need rest periods. There shpuld be no morethan 15 services per month. Older boars canoccasionally be allowed to mate twice a day, butnever more than 6 times a week, with a maximumof 20 times a month.

It is important to record the boar’s activity and the results obtained, sothat his performance can be assessed. The fertility of the boar isindicated by the size of the litters he produces and the percentage ofsows in-pig after a first service (insemination rate). The information torecord is:? the date of the service;? the identification (name or number) of the sow he has served;? the date of farrowing (which will tell you if the sow wasinseminated at the first service);? the size of the litter.
In this way the performance of the boar can be compared with otherboars and on the basis of this decisions about keeping or replacing him
can be made. It is important to remember however that the quality ofthe sows also has an influence on litter size and insemination rates.

Pig breeding37

Feeding and housing the boar
Boars should be kept neither too lean nor too fat. They need plenty of
exercise. In very hot conditions or when suffering from fever, they canremain infertile for a long time. A boar that is ill should be rested for 1
to 2 months and be replaced by another for this period.
Boars should be housed in individual pens, for if they are kept with
non-pregnant sows it becomes impossible to tell whether and when hehas served the sows, and whether or not they are in-pig. It is therefore
important to separate the boar from them.

4.3

The birth and care of the new-born piglets

On average delivery will take place 115 days after conception (3months, 3 weeks and 3 days). The sow will usually farrow during thenight or evening. In the last 14 days of pregnancy the udder will
increase in size. It feels firmer, and the nipples stand out more towards
the end of the pregnancy. In gilts the udder begins to develop after twomonths of pregnancy.
Preparation measures
About a week before the expected delivery date the sow should be put
in a pen of her own, which should be disinfected first. Before going
into the pen, she should be wormed and treated for lice and mange.
She should be washed with soap and lukewarm water and then rinsed
with a mild disinfectant. If there is any risk of disease for the newborn piglets the sow and the pen should again be washed anddisinfected 2 days before farrowing.

If you are not using a farrowing crate the sow should have plenty ofstraw and litter to make a nest for the piglets. If she is in a crate you
should make a nest of fine bedding material for them.
In (semi-)intensive units she should also be given plenty of litter.
Avoid using very fine litter however, because the sow likes to chew
her litter into small pieces, and if she is frustrated in this she will startto gnaw at the pen.

38

Pig keeping in the tropics

On the day of farrowing the sow should not be given her normal foodbut only laxative food (green fodder, for example) to ward off
constipation (see Paragraph 4.4)
BirthAbout a day before the birth of the first piglet, the udder will start tolook much redder. A white or clear fluid can now be extracted fromsome of the teats. The sow will be more lively, alert, restless and she
may start to bite. She scrapes the floor with her forefeet and sweeps
the straw bedding into a corner with her snout to make a nest.
Just before delivery, the udder will swell and the sow will calm down.
The birth of the first piglet is preceded by a bloodstained fluid oozing
from her vagina. In gilts the fluid may be released earlier. During thebirth the piglets are still enclosed in a membrane which will usually
break open as they are born. Piglets are born in the head-and-tailposition. On average a piglet will appear every 15 to 20 minutes, butparticularly small piglets may be born in very quick succession. Many
piglets are born still attached to the umbilical cord. This can be left, as
it usually soon breaks off on its own.

Figure 12: The sow and the new-born piglets (Barbera Oranje).

The sow may expel some of the afterbirth in between delivering eachpiglet, but the afterbirth is usually expelled all at once, 30 minutes or
Pig breeding39

an hour after the birth of the last piglet. The sow may suck blood fromthe afterbirth to build up her strength.
Piglets that are born premature (at 110 days or earlier) haveparchment-like skin, which is often very red with no hair or only very
short bristles. They may have misshapen claws, screwed-up eyes anddifficulty in breathing. They stray through the pen trying to find theudder. Most of them will not survive. Normally about one pig in 20 isstill-born. Older sows have a higher percentage of still-born piglets.
Although there are normally very few complications at birth it isadvisable to be at hand, problems which can occur during the birth aretreated in Paragraph 4.4.
Care of the new born piglets
A few minutes after the birth the umbilical cord may be pulled gently
away or cut if necessary (to about 5 cm length). After the birth thenavel of each piglet should be soaked in a cup of iodine solution toprevent inflammation and tetanus.
Each piglet should be rubbed carefully dry with a cloth and put onto
the udder. Their groping and sucking will encourage the sow to farrow
and to let down her milk, and it is important that the piglets
immediately take advantage of the valuable colostrum that will protect
them in the coming weeks against diseases (see Paragraph 4.5).
Piglets that have difficulty in breathing (weak irregular breathing) orthat appear to have died can be helped by holding their hind legs up in
the air. By pressing their chest (thorax) rhythmically their breathingcan be stimulated. Pouring a little cold water over their head and chest
can help, but the piglet should be dried off immediately afterwards.

In some cases, it may be necessary to trim the piglets’ teeth to prevent
them biting the udder. More information about this is given in
Paragraph 4.6.
If the sow does not produce enough milk the piglets should betransferred to another sow if this is possible; otherwise they will haveto be given extra food by hand (see Paragraph 4.5).

40

Pig keeping in the tropics

Anaemia
Young piglets kept on concrete floors may quickly develop serious
anaemia (a shortage of iron in the blood), because the sow’s milk does
not contain enough iron to cover the piglets’ needs. After two or three
weeks they become pale and their rate of growth drops. They may
develop a fat neck.

Anaemia can be prevented from birth by putting a shovel of ‘clean’iron-rich soil or compost into a corner of the pen every day. Clean soil
is soil which has not been in contact with other pigs, so that there is nodanger of worm contamination. The piglets can rummage around in it
and take up some of the iron in the soil. Most of the red, brown andyellow soils in the tropics contain adequate iron. Piglets (0 - 3 daysold) may be injected with an iron preparation, if available. Wood ash
can also be put into the pen. This will not provide iron, but it does
contain other important minerals.

4.4

Problems related to the birth

Although there are normally very few complications at birth it isadvisable to be at hand. If the whole process of delivery takes longer
than 8 to 12 hours then there is something wrong. In particular the last
piglets may be born in the membrane and will suffocate if they are nottaken out. It is also true that sows do not pay much attention to theiroffspring until all the litter has been delivered. Piglets that waste notime in searching for milk may easily be crushed if the sow lies down
again in the course of the farrowing. By being on hand to intervene intime this can be prevented.
A sow will not always accept human company whilst she is farrowing.
Remain at a discreet distance and be ready to intervene if it appears
really necessary.
Slow Delivery
If the sow does not seem to be making any headway and delivery
seems to be taking a long time, the first piglet may have to be helped

Pig breeding41

out by hand. For this the utmost hygiene is essential:- the sow’s rearend should be thoroughly cleaned and even disinfected, as should theoperator’s hands. Grease the hand and the vagina with vegetable oil or
Vaseline (avoid soap) and work the hand slowly into the vagina with aslight rotary movement. Simply by doing this it is possible that thesow will start her contractions and push the piglet out.
If this does not work the sow can be injected with 2 cc of oxytocin(not more), which is available on the market under different names. If
this has no effect after an hour the piglet will have to be released
manually, preferably by someone with a small hand which is clean andwell lubricated. If still no progress is made another injection may be
given.
If the piglet is really too big a caesarean operation is the only solution.
If there is no vet at hand this may not be possible and the sow will
have to be slaughtered. It is obviously preferable to try to prepare forsuch eventualities in advance.
Accidental killing of the piglets by the sow
It is quite normal for sows to eat the afterbirth and any still-born
piglets. Some sows, especially young gilts, can be aggressive towards
their litters. The reason for this is not clear. During farrowing an
inexperienced mother may become frightened by the new-born
piglets; she may try to avoid them and start biting. If this happens thepiglets should be put in a box and kept warm (possibly with a heatinglamp). The mother will usually quieten down. If she doesn’t she could
be given some beer (1 or 2 bottles) after farrowing. If it is available a
tranquilliser (or sedative) such as ‘Stresnil’ (2 mg/kg) can be injected.
Some people maintain that it is by eating the afterbirth that the motheris encouraged to start on her piglets too.
The sow becomes ill after farrowing
The most common disorder affecting sows after farrowing is an
inflammation of the uterus (metritis) or of the udder (mastitis).

42

Pig keeping in the tropics

Sometimes they are found in combination. The sow appears dazed,
refuses to get up and to eat, and is feverish.
? metritis
This is recognisable by a whitish-yellow and/or ill-smellingdischarge from the vagina (although a small amount of reddish
mucus is normal for a few days after the birth - it is not always verysignificant). At any sign of a bloodstained, ill-smelling liquid
exuding from the vagina checks should be made to see if there are
any piglets remaining inside. If so they must be released as
described in the paragraph above on ‘Slow delivery’.
? mastitis
In this case one or more of the udders may become hard andswollen, turning red to reddish-blue in colour. This usually starts atthe back of the udder. Milk production drops rapidly and the piglets
become hungry, starting to squeak and screech.
If the sow has a temperature of over 39.5 °C. she should be treatedat once. As soon as possible she should be given a 5 cc injection ofoxytocin (always read the label first) and an antibiotic(penicillin/streptomycin, (oxy)tetracyclin or chloramphenicol). If
after 24 hours this treatment has no effect the treatment should be
reviewed.
? constipation
It is normal for sows to stop eating shortly before farrowing. Thiscan however bring on constipation and a constipated sow may
become restless and neglect her new-born piglets.
Constipation can be eased by laxative foods (leafy greens , fruitsetc.). Oil or lard can also be mixed with the food. If it persists castor
oil (wonder oil) or Epsom salts can be given. The salts should be
dissolved in a small quantity of water.
In order to prevent constipation before farrowing, one or two
tablespoons of Epsom salts should be mixed with the feed each day
and extra leafy green foods should be given.

Pig breeding

43The hungry piglets should be kept warm (lamp) and given
additional feed of goat or cow’s milk, or a sweetened bean meal
porridge. In extreme cases the piglets should be put on another sow
or artificially reared (see para. 4.5 below).

4.5

Rearing motherless piglets by hand

If a sow dies shortly after farrowing the piglets will have to be rearedby hand, or by another sow. Rearing piglets by hand is very timeconsuming and often unsuccessful. It is far more effective to put thepiglets on another sow that has recently farrowed (less than 3 days).
This is usually more successful. Similarly, if a particular sow does notproduce enough milk for her litter, some of her piglets can betransferred to another sow. If this does not work, or if you have nosow available, the piglets will have to be reared by hand.
Put the piglets into a clean preferably straw-filled pen and keep themwarm. If possible hang a heat lamp in the pen at night and athermometer. The ideal temperature at first is 30°C (day and night)
coming down to 25°C after a fortnight. Throw some soil in a corner ofthe pen to prevent the animals from becoming anaemic.
Feeding orphan piglets
It is essential that newly-born piglets receive colostrum straight after
the birth to build up their natural resistance. Colostrum is the first milkthat the sow produces after farrowing. If the sow dies whilst
farrowing, the colostrum will have to be taken from another farrowing
sow for the piglets. If they get no colostrum their chance of survival isvery small.

Cow’s or goat’s milk can be given, perhaps sweetened with sugar or
syrup, to piglets who have managed to obtain colostrum. The milk
should not be diluted, as sow’s milk is very concentrated. It should be
warmed up to slightly above body temperature (37° - 40°C) in a pan
lowered into a larger pan containing boiling water (bain-marie).

44

Pig keeping in the tropics

If a sow dies whilst farrowing her piglets will not have learnt to drink.
The milk should be fed on a little spoon or in a feeding bottle. You
will have to make sure they take it in.
Later the piglets can be taught to drink from a shallow trough by
gently holding the snout in the milk. After every feed the bowl must
be thoroughly cleaned, dried, and occasionally disinfected. To avoid
indigestion the piglets should not be given too much at one time.
In order to encourage them to drink by themselves, boiled lukewarm
water (about twice the quantity of a milk feed) should be put in the
pen after the last feed of the day.
The feeding programme
For the first two days the piglets should be fed at regular intervals 5times a day, for about 10 minutes each time. On the third and on the
fourth day they should be fed four times a day, and after that 3 times aday. After 14 days, increase the quantity of milk at each feed, but
gradually decrease the number of feeds per day. Gradually changeover to more solid feed, so that by the age of about three weeks theyshould be able to take regular feed. If no nutritious feed is available
they should continue on milk for a while longer. The weaker brothers /sisters can be fed four times a day for a longer time. Table 2 serves asa guide.
The figures in the table are maximum quantities - it is better to give
too little rather than too much feed. There should be a continuous
supply of water available, which should be boiled to avoid any
contamination.
Table 2: Feeding programme for orphan piglets.
Day
1
2
3
4
5-7
8-9
10-11
12-14

Number of feeds
5
5
4
4
3
3
3
3

Pig breeding

Quantity each time (ml)
30
40-45
60
70
80-100
120
140
160

45

As soon as possible the orphan piglets should move onto regular food.
This should be of good quality, protein-rich, and easily digestible. It
should be remembered that, despite the amount of care they receive,
hand-reared piglets will never grow as fast as those reared by a mother
sow.

4.6

Looking after and weaning piglets

Teeth trimming
If the piglets prove turbulent
or aggressive, their tusk teeth
should be trimmed. This willstop them fighting for theteats and aggravating the sow
by biting them. Only the
points of the teeth should be
removed. If any more isremoved there is a risk ofdamaging the mouth. In
commercial units the points
are filed off (Figure 13).
Castration
Male piglets are castrated toprevent their meat from Figure 13: Trimming the piglets’smelling strongly, and also to teeth.
make sure that they are
manageable when they become sexually mature. Castration should bedone in the first two weeks of a piglet’s life. The animals should be fit
and healthy and if this is not the case it is better to postpone theoperation.

To carry out the castration two people are needed, the person carryingout the small operation and an assistant to hold the piglet. The pen
should be dry and very clean. The assistant takes the pig by the hindlegs and holds it firmly between his/her legs, the piglet’s head pointing
46

Pig keeping in the tropics

Figure 14: Castration of a young boar (after Eusebio, 1980).
Pig breeding47

towards the ground. The other person has a very sharp knife that has
been thoroughly cleaned with a disinfectant (Figure 14 shows thesteps to follow).
Afterwards the wound should be washed thoroughly with adisinfectant.
The other testicle is treated in the same way.
Weaning the piglets
Piglets should be weaned when they are about 8 weeks old. It is best
to take the sow away from the piglets, rather than leaving her in the
pen and removing the piglets. This is because piglets should not be
perturbed by the loss of their familiar nest, and because the sow will
come on heat again quicker. In the last few weeks the piglets should
already have started getting used to eating from a trough alongside
their mother, and now they should just continue doing so. They willneed protein-rich feed as they will be growing fast (see Chapter 6).

At the age of 3 months new breeding sows or boars can be selected(see Paragraphs 4.1 and 4.2).

4.7

Record-keeping

For those who intend to keep a number pigs for breeding purposes it isessential to have a good system of record-keeping. This will help tokeep track of developments, make comparisons and take decisions on
the management of the herd. It will also have a direct positive impact
on daily management.
Good record-keeping means noting down simply and clearly allimportant details and events. It can also be used to provide and record
information for future activities - it is important for example tocalculate and note the next date for checking whether a sow is on heator the date when she should farrow. Such information should bemarked on a calendar, so that any necessary preparation can start wellin advance (for example preparing the farrowing pen for the sow).

48

Pig keeping in the tropics

A good system of record-keeping requires little more than a notebook
or exercise book and, using a few pages for each sow, noting down all
the important events.
Relevant information to record would be for example:? In the case of a breeding sow:
• The name of the sow• The month and year of her birth• Her parents’ names? Important events:• Date of her first heat
• Date of 2nd heat
• Date of 3rd heat
• Date of mating, and name of the boar
• Result of the heat check 3 weeks after mating (did she come onheat again?)If there are no signs of heat she must be in-pig, and the date of
farrowing can be established (115 days after mating).
If she has come back on heat she will now have to be put to theboar again - Calculate the date when she might come back onheat (3 weeks after mating).
• Anticipated date of farrowing – mark this one in a calendar!
• The date for putting the sow in a farrowing pen (1 or 2 weeks
before farrowing). Mark this in the calendar too!
• Actual date of farrowing• Size of the litter, number of healthy piglets , and number of stillborn piglets• Number of piglets that have survived and have been successfully
weaned (this gives an idea of the sow’s mothering qualities)? Other information to note:• Dates of illness, nature of the problem and the treatment or
medicines administered.
• Information on the piglets, e.g. vaccination information.

Pig breeding49• If a piglet is selected for further breeding, such information
should be transferred to the new page of records opened for that
piglet in its new role as a breeding sow or boar.
Here is an example of a typical set of records:
Sow: Marianne.

Date of birth: April 1996
Parents: Sow Suzy and Boar Patrick

15th October 1996
7th November
29th November
30th Nov.
21st December

first heat
2nd heat
3rd heatserved by boar Hannibal
Check for heat. No signs (–), she is therefore in-pig
Birth date can be established, that is 115 days aftermating
Expected farrowing, written in calendar
Separate Marianne from the others
Marianne has been wormed and washedFarrowed: a litter of 4 boars and 3 sows, 1 piglet
still-born (dead)Weaning of the litter: 3 boars and 3 sows (one of
the boars has died)

25th March 1997
15th March
18th March
26th March
21st May

Paragraph 4.2 has suggested which records should be kept to monitor
the boar’s activities.
Using Table 3 the date of farrowing can be worked out, if the date ofsuccessful mating is known (date of mating + 114 days).
Marking the pigs
Being able to identify the pigs is essential if records are to be kept andmanagement activities planned. As long as you don’t have large
numbers of pigs there is no problem recognising them and no need toworry about marking them. However when there are so many pigs thatthey become difficult to distinguish it is time to introduce anidentification system. Giving your animals names also helps, and it iseasier to discuss them. They might even respond when you call them!

50

Pig keeping in the tropics

Table 3: Farrowing table.
Date of mating
Jan 1
Jan 6
Jan 11
Jan 16
Jan 21
Jan 26
Jan 31
Feb 5
Feb 10Feb 15
Feb 20Feb 25

Expected farrowing
date
Apr 26May 1
May 6
May 11
May 16
May 21
May 26
May 31
Jun 5
Jun 10Jun 15
Jun 20

Mar 2
Mar 7
Mar 12
Mar 17
Mar 22
Mar 27
Apr 1
Apr 6
Apr 11
Apr 16
Apr 21
Apr 26May 1
May 6
May 11
May 16
May 21
May 26
May 31
Jun 5
Jun 10Jun 15
Jun 20Jun 25
Jun 30Jun 25
Jun 30
Jul 5
Jul 10Jul 15
Jul 20Jul 25
Jul 30
Aug 4
Aug 9
Aug 14
Aug 19Aug 24
Aug 29Sep 3
Sep 8
Sep 13
Sep 18
Sep 23
Sep 28
Oct 3
Oct 8
Oct 13
Oct 18
Oct 23

Date of mating
Jul 5
Jul 10Jul 15
Jul 20Jul 25
Jul 30

Expected farrowing
date
Oct 28
Nov 2
Nov 7
Nov 12
Nov 17
Nov 22

Aug 4
Aug 9
Aug 14
Aug 19Aug 24
Aug 29Sep 3
Sep 8
Sep 13
Sep 18
Sep 23
Sep 28
Oct 3
Oct 8
Oct 13
Oct 18
Oct 23
Oct 28
Nov 2
Nov 7
Nov 12
Nov 17
Nov 22
Nov 27

Nov 27Dec 2
Dec 7
Dec 12
Dec 17
Dec 22
Dec 27Jan 1
Jan 6
Jan 11
Jan 16
Jan 21
Jan 26
Jan 31
Feb 5
Feb 10Feb 15
Feb 20feb 25
Mar 2
Mar 7
Mar 12
Mar 17
Mar 22

Dec 2
Dec 7
Dec 12
Dec 17
Dec 22
Dec 27
Dec 31Mar 27
Apr 1
Apr 6
Apr 11
Apr 26
Apr 21
Apr 26

Pig breeding51

There are various methods of physically marking animals, but in thisAgrodok we will only consider notching. We will not discuss
eartagging because the use of eartags requires special equipment
which is not easily available. All the animals should be marked when
they are young.
? Notching
Notching involves cutting small pieces of skin out of the edges ofthe ears. By varying the pattern of the cuts you can individualise theanimals for identification. This is a very cheap method requiring
only a very sharp knife (disinfected, of course!). The disadvantagesof the method are that it takes time ‘to read’ the patterns (or codes),and that problems can arise if the ears are damaged.
In Figure 15 an example of notching is shown. In this figure thecodes used on large farms are shown. A value is assigned to eachnotch on each side of the ear. By adding up the values marked on
the ear the sow’s number can be known.
You can of course
devise your own system of codes adapted to your particular
circumstances.

Figure 15: Notching and its codes (after Holnes, 1991).

52

Pig keeping in the tropics

5

Fertility disorders

5.1

Poor oestrus show in sowsIt sometimes happens that sows do not come on heat at the expected
time. Gilts should normally come on heat at 6 to 8 months of age, andsows should do so within one or two weeks of weaning their litter. If
there seems to be no heat, it may just be that the heat has passed
unnoticed. But it may also be a problem related to the health andcondition of the animal, or a genetic problem passed down from theparents. Gilts that do not come on heat should be replaced. Whenselecting females for breeding, those that have a long and easily
detectable oestrus period should be kept.
If a mother sow does not come on heat within 14 days of weaning,
there are various possible causes:? The suckling period has been too long - the shorter the period, thequicker she will come on heat again.
? She is in poor condition.
? She has been receiving low quality or too little feed (her ration
should be increased, not decreased after weaning).
? Very high local temperatures ( > 35 °C).
? A lack of light in her pen.
Oestrus can be brought on by:? Taking the sow away from the piglets during weaning, rather thanremoving the piglets.
? Putting the sow in a pen next to the boar after weaning.
? Bringing her into contact with the boar regularly after weaning.
If these measures don’t succeed a hormone preparation PG600 is
sometimes available that can be tried. This should be done in
consultation with the vet or the livestock extension service.
It occasionally happens that a sow thought to be pregnant (i.e. no heats
noticed after mating) does not finally deliver. In this case a problem
Fertility disorders

53

may have occurred after mating, resulting in her infertility or a
miscarriage. This sow should be culled.

5.2

Diseases leading to fertility disorders

Brucellosis and leptospirosis (described below) can both result in thesow miscarrying. Miscarriage (or abortion) is a termination of thepregnancy before its proper term, with the foetus and the placenta
being rejected. Some sows eat this up very quickly with the result thatthe abortion occurs without being noticed.
The diseases are not the only causes of miscarriage. Sometimes
completely healthy animals will abort for inexplicable reasons. Thisoccurs very rarely however with relatively few cases reported every
year. More alarming is the occurrence at the same time of several
cases on a single farm. This would indicate a disease-related problem
which could spread rapidly amongst the animals and to other farms.
If several miscarriages occur together the cause may be one of thediseases mentioned here, or swine fever or swine erysipelas which arecovered in paragraph 7.5 below. As soon as possible the vet or the
livestock authorities should be warned.
? Contagious abortion (Brucellosis)
Brucellosis in pigs is not caused in the same way as in cows, sheep
and goats. An outbreak can result in sudden abortion by pregnant
sows, followed by temporary or permanent infertility. The sows
may abort at any stage in their pregnancy. Some animals may
become crippled (inflammation of the joints) and boars may
develop an inflammation of the scrotum, with swelling and pain.
There is no treatment for this. The disease may disappear after awhile, but it often reappears. In most cases the whole herd will haveto be slaughtered (and this is required by law in some countries).
The entire holding should be cleaned and disinfected. For at least
two months no pigs should be allowed on the site. New animals
should be blood-tested by the veterinary service.

54

Pig keeping in the tropics

Prevention: an infected animal brought in from outside (such as aboar) is usually the cause (the disease can be transmitted bymating). If the sow is mated off the farm she may return with thedisease. One should be very cautious when bringing outside animals
onto the site. The disease can also be transmitted to humans!
? Weil’s Disease (Leptospirosis)
This disease is marked by sudden abortion by a number of sows,
usually towards the end of their pregnancy. The piglets are often
different in size, as they have died in the womb at various stages ofthe pregnancy. Sometimes very weak piglets are born at the normal
time. After the abortion there is no loss of fertility in the sows andthe disease dies out on its own accord within a few months.
During a leptospirosis epidemic abortions can be prevented if all the
pregnant sows are given two injections of dihydrostreptomycine indoses of 25 mg per kg. body weight, with an interval of one week inbetween each injection.
? Smedi virus
Infection by the Smedi virus (PARVO) is very similar to infection
by Weil’s disease. Recently bought gilts in particular (who have notdeveloped any resistance to the viruses present on the holding) may
deliver a number of still-born piglets. These are often full-term oreven overdue, but they will have died at different stages of thepregnancy, and will therefore vary in size. Once exposed to thedisease the animals develop a resistance to it and future breeding
can take place normally (such gilts should not be culled!).

Fertility disorders55

6

Pig feeding

6.1

Introduction

Pigs are in general not particular about their food, which can be ofboth animal and vegetable origin. Although they accept most foods,
this does not imply that the quality of their food is not important. Pigs
won’t thrive on grazing and fibrous feed alone.

Figure 16: A feeding pig (from: Udo,1985).

It is perhaps unfortunate that pigs share the same tastes andrequirements as humans. This means that they are in directcompetition with them for important parts of their production: thecereals, roots and tubers, milk and milk products. Only local
circumstances can determine to what extent such competition is
acceptable. In resource-poor areas the advantages of using cereals forexample as pig food should be considered very carefully. Normallypigs will have to make do with feed that is not directly useful to man,and with waste products. This includes agro-industrial by-products(bran, molasses etc.), kitchen waste, and garden or agricultural refuse.

56

Pig keeping in the tropics

6.2

Nutritional requirements

There are a number of essentials to be provided through the normal
rations:? Dry matter
Pigs like all animals need to fill their stomach and intestine with acertain amount of bulk, normally indicated in terms of dry matter.
The maximum that pigs in the tropics can eat is about 5 kg dry
matter per day (the lactating sows usually).
? Energy
A pig needs energy in its food in order to:• Maintain its body temperature and normal body processes (e.g.
digestion).
• Remain active and mobile.
• Develop and put on weight.
• Maintain its reproductive capacities: a healthy sex drive, strength
to nourish the foetus and to produce milk...
Starchy and fatty foods are the best sources of energy (see next
paragraph). The body also converts starch into body fat and, if
given sufficient good protein, into meat.
? Protein
Protein is necessary for physical development - growth, breeding
and milk production. Protein quality is as important as quantity.
Some protein of animal origin should be included if possible.
? Minerals and vitamins
These play an important role. The minerals calcium andphosphorous are very important, but trace elements such as copper,
zinc, iron etc. are also needed in small quantities. For optimum
production (growth, breeding, lactation) a good vitamin supply isessential.

Pig feeding

57

6.3

Sources of energy, protein, minerals andvitamins

Energy sources
Starchy products such as root and cereal crops are the cheapest
sources of energy. Oils and fats contain a great deal of energy but are
more expensive. If necessary proteins can be used as an energy source
but they are very expensive.

Cereals, legumes (which also contain a lot of protein), tuber and root
crops are rich sources of energy. Agro-industrial by-products can play
an important part in feeding pigs (flour milling waste, waste oil andfats etc.). Young green fodder and kitchen waste can also provide
energy.
Sugar is a very good source. It is richer and can be obtained and fed inits unpurified form as molasses. Molasses should be used with carehowever, as it moulds and ferments very quickly. If given in large
quantities it can cause diarrhoea. Molasses is a useful additive to make
unpalatable food more appetising as it consist of 50% sugar!
Protein sources
Here again not only the quantity but also the quality is important. The
quality is determined by the origin of the protein. Protein of animal
origin (milk, meat, fish...) is with few exceptions of high quality.
Vegetable protein is less rich but there is a lot of variation in the large
group of vegetable proteins. Soya protein is of high quality, pulses
good, and cereal protein of moderate quality.

Good protein sources are: pulses, young green fodder, animal waste
products, and kitchen waste containing soya, cotton, peanut and lupin
seed (sweet lupin).
The protein content of the feed is so important because pigs have noother source of protein (For cows, buffalo, sheep and goats protein
quality is less important, because various processes take place in the58

Pig keeping in the tropics

stomach to produce protein or to increase the quality of the protein in
the food received.).
Vitamin and mineral sources
In a varied diet the vitamin supply will normally be adequate, but if noanimal protein is fed vitamin B12 levels may suffer. To balance thediet a shovelful of cow, buffalo, sheep and goat dung (ruminating
animals) should be put into the pen every day. This type of dung
contains all the B-vitamins.

Where vitamin compounds (with calcium and phosphorous) areavailable a dose of 50 - 100 gm per animal per day is advisable (pigsabove 15 kg). Boiling tubers and kitchen waste in seawater can alsosatisfy mineral requirements (with the exception of phosphorous)
economically.

6.4

Feeding in practice

Fat
Fat levels in foodstuffs can vary considerably but there is rarely any
danger of deficiency. If the feed contains too much fat this may cause
diarrhoea. The fat in the feed has an impact on the quality of the pork
produced. Products with an oily fat, such as maize and rice, will give atender pork. Those whose fat stays firm even at high temperatures(copra for example) will give a compact bacon quality. For
preservation purposes this is important, as the firmer the pork is, thelonger it can be kept. In general, the fat level of typical feeds is low.
Fibrous foodPigs, in contrast to cows and other ruminants, prefer fodder that is low
in fibrous tissue. They have difficulty in digesting crude fibre, whilst
ruminants have a composite stomach in which fibrous tissue can be
broken down easily.

The amount of crude fibre varies considerably in different foods.
Young green feeds, tubers and roots are low in crude fibre, as are
Pig feeding59many cereals and seeds. Animal products contain less than 20%. The
amount of crude fibre in a growing plant increases as it gets older
however. Pigs can therefore still digest young green fodder whilst
older plants are more difficult. Stalky fibrous plants are therefore
poorly converted by pigs. Hay and straw is most unsuitable, although
they will eat it in time of need. Hay and straw can serve to keep older
animals alive, but not for physical development, growth andreproduction.
Dung consumption
In difficult circumstances pigs will eat their own excrement. This isbecause they find bacteria in the dung which are digestible and rich invitamins. This behaviour is therefore a way of increasing their nutrient
intake.
Liquids
Water or other liquids (milk etc.) should be available in plentiful
quantities, as pigs not receiving enough liquid will react by reducing
their intake of nutrients.
Food hygiene
Feed troughs must be emptied if the food is not eaten and must be
regularly disinfected, since mouldy or rotting food will lead todiarrhoea which can be fatal to young pigs.

6.5

Feeding pigs, from weaning onwards

The remarks in this section apply to holdings where most of the feedis produced locally. In areas where manufactured feeds can be boughtthese may be preferable if the farmer can afford it.
Pigs in general need a ration with a minimum protein content of at least 13%.

60

Pig keeping in the tropics

Nevertheless:? Piglets that have just been weaned need protein-rich feed (20%protein) because they need a good start in life and are growing fast.
At about 3 months of age this can be reduced to 13%.
? Sows and gilts who are pregnant need extra protein in the final
stages of their pregnancy, because at this time the unborn piglets aredeveloping very fast.
? A sow suckling her litter needs a lot of energy-rich food (seeParagraph 6.3) to be able to produce enough milk.
? A young breeding boar will not need extra nutrition, because, tobuild up his strength correctly, it is important that his development
is not forced.
The protein ration
The foods mentioned in paragraph 6.3 need to be combined to achieve
the right protein level in the daily ration.

Peas, beans, lentils, china beans, vetches contain about 20% protein,orobus and chick pea about 16%; sweet lupins (boil!) and soya beans
about 30%; shelled groundnuts contain 24% protein.
Cereals and cereal waste will not provide more than 10% protein.
Tuber and root crops are usually very poor in protein and must be
supplemented with protein rich feed (e.g. soya, animal or fish meal or
milkproducts).
In order to prepare a normal protein ration at 13% we will have to mix 1 part ofbeans (20%) with 2 parts of cereals (10%).

If young green fodder (vegetable leaves etc.) is available, 3/4 kg
peas/beans or 1/2 to 3/4 kg soybean cake or cotton cake per day will
suffice if plenty of other (less nutritious) feed is given.
If milk or milk products, animal or fish meal are available they should
be fed in priority to the lactating sows and their piglets. Piglets
recently weaned can also be given some for the first weeks after
weaning.

Pig feeding61

If a pig is fed 1 kg of a 20% protein mixture every day the rest of thefeed can be composed of feed less rich in protein. If a 30% protein
level is possible then 750 gram of the mix is enough, and with 40%
level 500 gram would suffice. These mixtures have to besupplemented continually with other feedstuff, according to theanimal’s energy needs.
It is advisable also to add 0.3 kg of minerals to every 10 kg feed
mixture.
Some elementary precautions
Soya beans should be cooked before use, and shelled groundnuts must
be checked for mould before being used in the pig feed. If you are notsure of the origin or quality of certain foodstuffs, or if there is a danger
that they may be poisonous you should either discard or at least cookor boil them. Many poisonous agents cannot support very hightemperatures.

Cotton seeds, safflower seeds, and cabbage seeds are dangerous forpigs and should not be fed. Safflower cake can be fed but issometimes poisonous - feed in small quantities and observe the pigs
carefully.

6.6

Feeding a sow and her piglets

If sows are fed properly (not forgetting the water!), they will be able
to suckle their litter for 6 - 8 weeks. Any longer would not be
advisable as they will lose too much weight. During lactation sowsshould be given extra feed: approximately ½ kg meal per piglet perday, in addition to a ration of 1 kg meal (20% protein), with otherfeed.
At the age of 3 - 4 weeks piglets pass through a difficult stage. They
need more milk than their mother can produce and the supply of ironwith which they were born is almost used up. They should be given
easily digestible food (watery cereal porridge) until they start to join

62

Pig keeping in the tropics

the sow eating from the trough. The sow should be kept away from thepiglets’ feed. Ideally the piglets should get a little animal protein(18%). Also some young green fodder is very healthy for these piglets.
To supplement the iron deficiency a shovelful of soil should be put
into the pen every day. In intensive systems iron-injections are often
given whilst in free-range systems piglets get iron from the soil. Woodash provides other minerals.

Pig feeding63

7

Diseases, prevention and control

Local breeds are often resistant to diseases. The main problem withkeeping any sort of pig in free-range or semi-intensive systems is notdisease but disabling infestation by worms or other parasites.
It is in intensive pig keeping systems that disease is a greater risk,
because many animals are kept together in a small space. Infectious
diseases spread easily and quickly among the animals. In intensive
systems commercial breeds are often used and these tend to be lessresistant to disease.
Intensive pig production is a financial undertaking. Diseases can leadto production shortfalls (slower growth rates or loss of animals) and aloss of income for the farmer. In these circumstances it is essential totreat the animals, as long as the costs of treatment do not exceed theloss of income expected.
In free-range and semi-intensive systems farmers do not generally
have funds to spend on medical treatment. It is also possible that thepigs are not their only source of income. In such cases a drop in
production may be viewed as less important, and farmers may wish to
calculate whether the benefits of saving the sick animal and protecting
the others justify the cost of treatment.
In terms of prevention, if there is a high risk of an infectious disease
occurring, animals can be vaccinated to reduce the risk of losing them
all if a disease breaks out.
Whatever the circumstances, if at all possible, the advice of a vet
should be sought if there is disease on the holding. Despite all
preventive efforts, treatment with medicines may be the only solution
remaining.

64

Pig keeping in the tropics

7.1

Prevention by promoting natural resistance

Many diseases and health-related problems in animals can be linked toa loss of natural resistance as a result of feeding problems, a lack ofhygiene, or sudden changes in their environment (e.g. temperature,humidity).
Many problems can be prevented by taking the following measures:? Ensure that the pigs receive sufficient nutritious food.
? Provide shelter from the sun and the rain.
? Regularly move the animals into different enclosures and relocate
their shelters.
? Provide good housing, draught- and dust-free, where temperatures
are neither too high nor too low, and do not overcrowd.
? Combat anaemia (shortage of iron) by putting iron-rich soil in the
pen daily.
? Maintain good hygiene in the pens and feeding equipment (keepthem dry and clean).
? Be very careful when bringing new animals onto the holding fromoutside, as they may be carrying disease.
? Vaccinate the animals if you know there is risk of infectious
disease.
Prevention is better than cure. Not only are sick animals lessproductive, but modern remedies are difficult to obtain or even
unavailable in the tropics. They are often very expensive. For thisreason particular attention must be paid to the health of the piglets,
who are very vulnerable to disease, and whose early months lay thefoundations for their ability to resist later on (To a certain extent theloss of some piglets has to be seen as inevitable. In the Netherlands forexample a piglet death rate of 15 - 20 out of every hundred isconsidered acceptable.).
Spread of disease by infection
At any outbreak of disease it is essential to ensure that the disease is
not passed on to healthy animals on the footwear, clothing, tools etc.

Diseases, prevention and control

65

of those working with the pigs. Even insects, wild animals andearthworms can transmit disease. Therefore take precautionary
measures:? Give the sick animal a separate pen.
? Do not let people into the stable (they might have pigs at home andcarry germs away with them).
? After contact with a sick animal never touch other animals without
first having washed your hands and changed your clothes andfootwear.
The pen should be continually cleaned with disinfectant or sodiumhydroxide (NaOH, 5%). Whenever pigs are sent to slaughter theirhousing should be disinfected before new pigs are brought in. Anyanimals dying of a disease should be burnt to prevent further
contamination.
Even the meat of healthy pigs may be contaminated with germs. It istherefore important always to boil or to roast meat very thoroughly
before eating it.

7.2

Disease-causing organisms

Diseases are caused by specific types of organisms. Consequently totreat a particular disease you have to know which organism isinvolved and choose the appropriate medicine. A medicine badly
chosen is money wasted. The principle types of organism responsiblefor diseases are:? Bacteria
Very small and invisible to the naked eye. Antibiotics can killbacteria, but if antibiotics are not properly used the bacteria canbecome resistant them (see Paragraph 7.3 below).

66

Pig keeping in the tropics

? Viruses
Also very small, invisible even with a microscope! Virus diseases
are difficult to treat and there are relatively few medicines available.
Antibiotics are sometimes effective and there are vaccinations
available in some cases for preventive treatment.
? Parasites
These are small animals living on or inside the pig, such as various
types of worms, ticks, lice, fleas etc... Hygiene is an importantfactor in their prevention. Treatment varies with each type ofparasite.
Sometimes diseases are caused by a combination of harmfulorganisms. Pneumonia is an example, which can be caused by bacteria
or viruses (and usually by both at the same time), and also by parasites(lung worms and intestinal worms that have found their way into thelungs). Paragraph 7.6 describes pneumonia in more detail.
In Paragraphs 7.4 to 7.8 different diseases are considered, presented in
the following groups:? parasitic diseases (Paragraph 7.4)
? bacterial diseases (Paragraph 7.5)
? viral diseases (Paragraph 7.6)
? feed-related diseases (Paragraph 7.7)
? other diseases (Paragraph 7.8)
Before proceeding to consider the diseases individually, some criticalremarks on the use of medicines need to be made.

7.3

The use of medicines

Treatment for natural parasites
The routine use of medicines against parasites (e.g. worms) or bacteria
is common. The intention is to kill or greatly reduce in number theorganisms causing disease or weakness in the animal. These
Diseases, prevention and control

67

organisms nevertheless remain present in the animal’s surroundings
and represent a potential source of reinfection. This often implies that,
if no special hygienic measures are taken, repeated treatment withwormers or other medicines becomes necessary. These repeatedtreatments reduce the natural resistance of the animals. Eventually
damage by parasites can actually be much worse under repeatedtreatment than in circumstances where the animals are not treated (forfinancial or other reasons) and are obliged to rely on their naturalresistance to their environment.
It is therefore important, before using these medicines, first to assess
the losses one is likely to suffer as a result of disease or infection.
Secondly the likelihood of the treatment being properly applied andsucceeding (without inefficient repetitions) must be assessed.
In some cases it is considered useful to treat animals only
occasionally, in specific situations. For example one might choose totreat all animals arriving on the holding and not yet accustomed to the
new environment, as well as pregnant sows preparatory to farrowing(worming), and any animals weakened for some reason and whose
resistance is low.
Resistance to medicines
All disease-causing organisms are capable of developing resistance tomedicines. They do so when medicines are used in the wrong doses,
or too often, or without respecting the treatment times.
Antibiotics
Antibiotics are very useful medicines but they must be properly used.

? The body of a healthy animal harbours many useful bacteria; thosefor example in its intestines have the role of helping the animal todigest its food. Antibiotics however are devised to kill all bacteria
without discrimination. Unfortunately therefore when an animal istreated with antibiotics its good bacteria are also killed.
Consequently, although the antibiotics may effectively arrest the68

Pig keeping in the tropics

disease, they may also weaken the general condition of the animal.
For this reason give your animal all possible attention when it isbeing treated! (If you are able to, feed yoghurt to encourage therenewal of the useful intestinal bacteria.)? A treatment with antibiotics always takes a few days and a course oftreatment must be carried out to the very end. If this is not done thedisease will hit back again. There is a great temptation to break thetreatment off earlier, because it is nearly always the case that thebenefits of the antibiotic are to be seen shortly after starting thetreatment, and the medicines are expensive. But don’t be mistaken,
for ending the treatment early can leave the animal even more
severely ill, and the medicines (and the money) will have been
wasted.
? The meat of an animal recently treated with antibiotics must not beeaten or sold. The antibiotics enter the meat and will affect thehealth of the people eating it, who will get diarrhoea. If an animal isdestined for slaughter you must decide whether it is useful to treat itwith antibiotics, and judge the best time to slaughter it so that it canbe sold with the meat untainted.
There are often local medicines (medicinal plants) or treatments in use
which have been developed over many years. Do not neglect these
traditional practices, some of which have been shown to be successful,whilst not being as expensive and difficult to obtain as modern
medicines. Medicines that are used for human beings can also be
effective on pigs, as pigs and human beings have similar digestivesystems.
Products such as DDT have very dangerous side-effects for man and animals
and should on no account be used.

Diseases, prevention and control

69

7.4

Parasitic diseases

Intestinal parasites (worms)
Worms are one of the most serious threats to pig keeping; there are
more than 30 types affecting the intestines. The most important ofthese are the intestinal roundworm, the lung worm, the kidney worm,
the stomach worm, and the tape worm. Infection occurs when theworms’ eggs are eaten during the pig’s foraging for food; the eggs aremicroscopically small and are present in the soil, in the dung of worminfested pigs, in the vegetation at the bottom of ditches, wherever pigs
are to be found. In Paragraph 2.2 we described the importance of fieldrotation as a measure of worm prevention in semi-intensive systems.
In intensive systems prevention is achieved by ensuring excellent
hygiene.

Figure 17: Life cycle of the intestinal roundworm (from: Holnes,
1991).

Breeding sows kept outside will always be slightly contaminated withworms, but some infestation in older animals is not serious, as theseanimals usually have a measure of resistance. Young piglets however
are very vulnerable. To prevent the young piglets from being infected
directly after birth the sow should be wormed about 1 week before70

Pig keeping in the tropics

delivery (treatment which drives out all the worms). She should thenbe kept inside for delivery. To prevent re-infestation the pen should bewell cleaned every day. After worming, the sows should be washed toensure that there are no worm eggs clinging to them. All this being
done the young piglets have a good chance of being born into a wormfree environment.
Good wormers (medicines for expelling the worms) to be mixed withthe feed are chenopodium oil, sodium fluoride, piperazine
preparations, A-gard and thiabendazole 0,1%.
Lung worms
General hygienic precautions are necessary in controlling thiscondition. Typically the infected animals cough when they are made tomove around and they grow poorly. Riperol (or Levamisole) injections
are used in treatment, but are probably difficult to obtain in many
places.
Mange
This is a skin-irritation caused by small external mites such as thesmall grass louse. They provoke severe itching and irritation, with theskin between the legs, around the eyes, ears and neck being principally
affected. Treatment involves the removal of scales and dirt with soap
and water and a stiff brush. Afterwards the pig should be washed withcalcium sulphide or Lindane. Repeat this treatment several times.

Although Lindane is effective against mange and against otherparasites of the skin, it is very toxic and dangerous to humans! Its use
is prohibited in the Netherlands.
Smearing with coconut oil can be an effective control in cases of light
contamination.
Lice
These are blood suckers that also cause irritation of the skin. They canbe kept away to a certain extent by planting a pole sturdily in the

Diseases, prevention and control

71

ground at an angle of 45° with an old sack wound around it immersed
in crude oil or used motor-oil.
The insecticide benzene hexachloride is a very effective remedy (0.1 0.25% solution) against lice.
Sand fleas
The sand flea lives on plants and dry grass and passes from them topiglets in particular. The female fleas delve into the skin of the host to
lay their eggs (usually between the claws and around the jaw). They
should be removed from their breeding places in the skin without
bursting the blisters, which are full of eggs. The best remedy is toclean out the breeding places and then smear them with disinfectant.

7.5

Bacterial diseases

Enteritis or inflammation of the intestineThis is a condition with a number of causes (a variety of microorganisms or inappropriate feed). It is not possible here to describe
them all at length. It is characterised by some of the following
symptoms: a loss of energy and interest, a high temperature, a loss ofappetite, diarrhoea (sometimes bloody), and weight loss. If the
problem is food-related, starve the animal and give only clean waterfor one or two days. After that, gradually increase the feed to normal
levels.

The cause of the problem may be a sudden change in diet, in whichcase the same procedure should be followed. There are a number ofcommon intestinal problems worthy of mention:? Clostridium enterotoaemia? This usually occurs in 1 - 5 days old piglets. There is no goodtreatment. The sows can be vaccinated, so that the piglets build up
anti-bodies through the sows’ milk. The piglets can also be given
injections of ampi/amoxycilline.
? Transmissible gastro-enteritis (TGE)72

Pig keeping in the tropics

? This can occur in pigs of all ages, resulting in watery soft diarrhoea.
No treatment is possible.
? Dysentery (Doyle)? Variable success can be had with one of the following medicines:
tylosine, spiramycine, organic arsenic and dimetridazole
preparations.
? Salmonellosis
Neomycine can be given for 3 days (20 mg/kg of body weight perday)? E. coli bacteria: Antibiotics are used - often Colistine.
TetanusTetanus bacteria can develop if a deep closed wound is received fromrusty metal (standing on a rusty nail for example). The animals finallydie as a result of severe cramps. There is no treatment.
Mastitis
This affects the tissue of the udder and can result in permanent
damage, with the result that breeding pigs can no longer be used.
Infection can be avoided to a degree by good hygiene on the holding.
If an udder inflammation is noticed, the milk should first be gently
milked out before injecting an antibiotic into the muscles or the udder.
Anthrax
This is dangerous both to humans and other animals. A blood-stained
fluid will be seen coming from all the body openings. The infectedanimals are usually found dead in the field. The body should not beburied but burnt, as the germs can survive in the soil for years. Cattle
should be kept out of all fields that have once been contaminated withanthrax.
Brucellosis (see also Paragraph 5.2)
This causes abortion in female animals and infection of the
reproductive organs in the male animal. Sterility may result. Althoughtreatment with antibiotics is sometimes possible for females, it isbetter to dispose of infected animals. The boars should be carefully

Diseases, prevention and control

73

controlled because the germs from the boar can be transmitted without
the boar itself being ill.
Trypanosomiasis
This is transmitted by the tsetse fly. The infected animals are feverish,lack appetite, and breathe very fast. Prevention is only possible byeradicating the fly from the region. Pig breeding is therefore almost
impossible in tsetse areas.

7.6

Viral diseases

Swine feverThis is caused by a very infectious virus. In pigs the following
symptoms may vary from almost imperceptible to very serious:? The animal may be very ill for a few days with a high temperatureand constipation, after which it recovers.
? The animal is seriously ill, runs a high temperature (between 41 42°C), with diarrhoea, an unsteady walk, possibly showing signs ofbruising indicating bleeding under the skin (brown blemishes).
In addition to these symptoms pregnant sows may abort.
In piglets the following symptoms are found:? Chronic cases show retarded growth and diarrhoea. The piglets lose
colour and slowly die.
? In acute cases diseased piglets huddle together, pale, with diarrhoea
and high temperature (41 - 42°C). They have an unsteady gait andmay display brown blemishes on the belly.
It happens that one piglet in the litter will suddenly die (pale bodywith skin bleeding), whilst the rest of the pigs remain unaffected.
There is no treatment for this disease; only a preventative vaccination
can reduce the danger. This vaccination (the so-called crystal violet
vaccine) is first administered at the age of 8 to 10 weeks and to sowsand boars twice a year thereafter.
74

Pig keeping in the tropics

African Swine Fever
This is not the same disease as ordinary swine fever. The illness starts
with a rapidly rising fever. Typically the animal will remain lively inthe early stages, eating normally. About 36 to 48 hours before dying it
becomes restless, stops eating, loses the use of its back legs and lies
down a lot. It may sometimes have weepy eyes and a discharge(occasionally bloody) from its nose; it vomits. Its skin is often
reddish-blue (especially on the legs).
There is no treatment and no vaccine for this disease.
Swine Erysipelas
This disease is often confused with swine fever. To illustrate thedifferences the two diseases can be compared as in Table 4. Treatment
is by penicillin injection and spot disease serum. It is not always
effective.
Table 4:
Swine erysipelas
constipation or other soft dungpink skin, often with intended bruising (youcan put your thumb in the bruise)lack of appetite
stiff, limping gait
screeches hoarsely when roused
disease manifests itself in hot weather
only one or few pigs ill in the herd

Swine fever
obvious diarrhoea
pale skin, bruising, not intended
often abnormal appetite
weak, meandering gait
gruntsdisease can occur at any time of year
several pigs ill at the same time

Pneumonia
Pneumonia may be caused by bacteria, viruses (usually by both at thesame time) or parasites (lung worms and intestinal worms that havefound their way into the lung). The condition is aggravated by keeping
too many pigs in a small space, low temperatures, draughts,
insufficient air humidity, and dusty surroundings. The illness is morecommon in the rainy season and at this time the pigs should have dry
and draught-free conditions. The animals start coughing, especiallyafter exertion and when roused, and they breathe with convulsions.
Their growth is retarded. If viruses and bacteria are the cause,
Diseases, prevention and control

75

treatment is by antibiotics (streptomycin - penicillin, tetracycline).
Ripercol R or Ivermectine is used if there are lung worms involved.

7.7

Feed-related diseases

Anaemia, or blood deficiency
This is an important problem, especially for young piglets kept
indoors. The piglets become very pale a few weeks after birth andtheir growth slows down. The cause is an iron deficiency in themother’s milk. This can be prevented by putting iron-rich soil (mudfrom the ditches, forest soil...) in the pen every day, giving the pigs
something to root in. This soil should not have been in contact withpigs previously, as there should be no risk of it carrying worms. Thisshould be done from the very first week. Very young pigs (0-3 daysold) can be given an injection of iron-dextron if it is available (this isvery common in (semi-)intensive systems).

Wood ash may also be put in the pen. Wood ash will not provide iron,but it provides other important minerals such as calcium andphosphorus which are important for the growth of the piglets’ bones.
Constipation
Constipated sows should have a 60 gm dose of linseed oil in the feed
every day. If this does not help 60 gm of Epsom salts should be given
and the sow should be made to take exercise.

7.8

Sunstroke

If a pig gets sunstroke, bathe (only) its head in cold water. If possible
give it some brandy or whisky with a teaspoon. Make sure it has
shade.

76

Pig keeping in the tropics

Further reading
Devendra, C., D. Thomas, M.A. Jabbar and H. Kudo, Improvementof livestock production in crop-animal system in rainfed
agroecological zones of South-East Asia. 1997, 116 pp., ILRI
(international Livestock Research Institute), Nairobi, Kenya. ISBN:92-9146-031-1.
Harris D.L., Multi-site pig production. 2000, 280 pp., Iowa state
Uninversity Press, Iowa,USA. ISBN: 813826993.
Hill, J and D.Sainsbury, The health of pigs : Nutrition, housing anddisease prevention. 1995, 448 pp., Black well Sciences, oxford, UK.
ISBN: 582061008.
Holness, D.H, Pigs., vol. 132, 1991, 150 pp., Macmillan press Ltd,Basingstoke,UK. ISBN: 0333523083.
Malcolmson, R.W.; Mastoris, S., The English Pig: a history. 1998,
192 pp., Hambledon, London, UK. ISBN: 1852851740.
Perez, R., Feeding pigs in the tropics. 1997, 185 pp., FAO, Rome.
ISBN: 92-5-103924-0.
Porter, V., A handbook to the breeds of the world. , 1993, 256 pp.,
[S.I.] : Helm Information. ISBN: 1-873403-17-8.
Research Institute for pig Husbandry, Applied Research in pig
husbandry in the Netherlands. 1991, 28 pp., Rosmalen: ResearchInstitute for Pig Husbandry.
Serres, H., Manual of pig production in the tropics. 1992, 262 pp.,
CAB International, Wallingford, UK. ISBN: 851987842.
Straw, B.E.; D'Allaire S.; Mengeling, W. L. Diseases of swine. 1999,
1256 pp., Black well Sciences, oxford, UK. ISBN: 63205256.
Whittemore, C.T. The science and practice of pig production. 1998,
704 pp., Black well Sciences, oxford, UK. ISBN: 0632 0500861.

Further reading77Useful addresses
FAO, Food and Agricultural Organization.
The Food and Agriculture Organization of the United Nations leadsinternational efforts to defeat hunger. Serving both developed anddeveloping countries, FAO acts as a neutral forum where all nations
meet as equals to negotiate agreements and debate policy. FAO is alsoa source of knowledge and information. We help developing countries
and countries in transition modernize and improve agriculture,
forestry and fisheries practices and ensure good nutrition for all.
Address: Viale delle terme di carcalla, Rome, Italy
Telephone: (+39) 06 57051; Fax: (+39) 06 570 53152
E-mail: FAO-HQ@fao.org ; web-site: www.fao.org
ILRI, International Livestock Research Institute
ILRI helps the world’s poor people build and protect their livestockbased assets so that these, not poverty, are passed on to the next
generation.
PO.BOX 5689, Addis Ababa, Ethiopia
Telephone: + (251)-1 463 215; Fax: + (251)-1461 252
E-mail: ILRI-Ethiopia@cgiar.org ; web-site www.ilri.cgiar.org

PTC+, Practical Training Centre
PTC+ is an international training institute, which focuses on all thelinks in the production chain on plant and animal commodities,(agricultural) technology, (food) technology and natural areas.
Training programmes are practice-oriented and mix theory withpractical classes. PTC+ offers “open entry” programmes, “tailormade” programmes and consultancy. Programmes are offered in the
Netherlands and/or at location.
It is the policy of PTC+ to search for partnerships and co-operation
programmes with national and international institutions abroad.

78

Pig keeping in the tropics

PTC+ Head Office,P.O. Box 160, 6710 BD Ede, The Netherlands
Tel.: +31 318 645700, Fax: +31 318 595869
E-mail: info@ptcplus.comPTC+ ; web-site www.ptcplus.com
Animal science department, WUR
Zodiac is the Animal science of the Wageningen University andresearch centre.The core-business of the department is scientificeducation and research in the area of animal sciences. The department
aims to contribute to a sustainable animal husbandry, aquaculture andfisheries
Marijkeweg 40, , 6700 PG, Wageningen,Telephone: +31c 317 483952; Fax: +31 317 483962
E-mail: info@animalsciences.nl ; web-site: http://www.zod.wau.nl/
ITDG, Intermediate Technology Development GroupITDG helps people to use Technology in the fight against poverty.
Bourton Hall, Bourton on Dunsmore, CV23 9QZ, Rugby,
Warwickshire, United Kingdom
E-mail: infoserv@itdg.org.uk ; web-site: http://www.itdg.org/
CABI, Common wealth Agricultural Bureaux
P.O.Box 633, Icraf complex, , Nairobi, Kenya
E-mail: cabi-arc@cabi.org ; web-site www.cabi.org
DIO, Foundation for veterinary Medicine for development
cooperation.
The DIO foundation gives support and advice in the field of animal
health and production to the poorer people of the world, irrespectiveof country of origin, beliefs or political interests. The main tool in ourefforts is the Veterinairy Information Service (V.I.S.), which is free toour target group. Furthermore, we try to help by giving advice on
animal diseases and other veterinary issues. Secondly we want topromote awareness in The Netherlands of the importance of animal
health in development co-operation. Our motto is: healthy animals,
healthy people!
Yalelaan 17, 3584 CL, De Uithof, The Netherlands
E-mail: dio@dio@dio.nl ; Web-site: www.dio.nl

Useful addresses

79Glossary
Bacteria

Microscopic organisms found in all organic
matter, and often the cause of disease in animals
and human beings.
Boar
Male uncastrated pig.
Colostrum
The first milk produced by the sow after thebirth of the piglets. It is rich in nutrients andanti-bodies against diseases, and is essential for
new-born piglets.
Complete mixtures Feed purchased and sufficiently balanced to be
fed without any other feed (except water)
To Cull
Kill an unwanted animal.
Dry matter
The non-water content of feed: cereals forexample consist of 20 - 30% water and 80 - 70%
dry matter
To Farrow
Give birth.
Fatteners
Pigs destined for meat rather than being kept forbreeding.
FoetusThe piglet in the womb of the sow before it isborn; all parts of its body are recognisable.
Gilt
A young female pig that has never had piglets.
Heat
The period of about 3 days in which a sow is
fertile and ready for mating (service).
In-breeding
Excessive breeding of males with females thatare closely related, resulting in deteriorating
quality of offspring.
In-pigPregnant.
Insemination
Impregnation, making pregnant.
Lactation
Milk production, suckling offspring
LitterEither 1. Bedding material, straw etc.....
or
2. The group of piglets produced by asow.
Molasses
Dark syrup drained from sugar during refining,of great nutritive value.

80

Pig keeping in the tropics

Nucleus feed
OestrusOestrus show
Parasite

Placenta
Ruminants
To Serve/service
Sow
Still-born
Sucklings
Umbilical cord
UterusVirus
Vulva
To Wean
Womb

A concentrated feed purchased to add to local
feedstuff to raise the quality of the ration.
Period of excitement in female animals, theperiod the sow is prepared to meet the boar andable to become pregnant, also heat.
The signs of a sow’s period of fertility, or heat.
Organisms that live at the expense of their host,another animal such as a pig. They live inside
the body (e.g. worms) or on its skin (e.g. lice,fleas). They are often a cause of disease.
The mass of tissue within the uterus by which
the unborn animal is fed and which is expelled
after the birth.
Animals (cows, goats, sheep...) with a complex
stomach enabling them to digest grasses andother vegetal foodstuff.
The act of mating or coupling.
Female pig.
Born dead, lifeless.
The piglets when they are still dependent on themother’s milk.
The string that joins the piglet to the placenta
while in the uterus.
Organ in the female in which the unborn pig
develops (also called womb).
Verysmall microscopic disease-causingorganism smaller than bacteria.
The opening of the female organs ofreproduction.
To end piglets’ access to the mother’s milk,whilst simultaneously accustoming them to solid
food.
See Uterus.

Glossary81