bluuebunny/crossref_metadata_2025 huggingface dataset:
Calving performance and calf survival in a twin-calving beef herd
Authors: Diskin M.G. , McEvoy T.G. , Sreenan J.M.
Published: June 2019

In suckler beef production it is estimated that 55% of the total cost is required to maintain and replace the breeding females while only 1095 of total feed energy intake is stored in the tissue of the calves and cows. The low reproductive rate of the cow is primarily responsible for this low efficiency. Even in a well managed herd, weaning rate Is about 0.95 calves per cow per annum or less. It Is frequently hypothesised that increasing litter size by inducing twin calving would increase output, biological and economic efficiency provided few extra Inputs were required. Although twinning may increase the efficiency of beef production, spontaneous twin-calving is frequently associated with an Increased incidence of calving problems, poor calf survival, retained placentae and longer rebreeding intervals. Such problems related to twin-calving cannot be studied unless the frequency of twinning is increased above the levels that occur spontaneously. Embryo transfer can be used to Increase the frequency of twin calving thus allowing a better assessment of the potential to Increase output. A suckler herd, with a high level of twinning, was established to determine the effects of litter size on calving performance and calf survival rates.
Farm animal welfare legislation in europe
Authors: Carter H E
Published: June 2019

There is mounting concern for the welfare of farm animals in all the countries of the European Community and the members states of the Council of Europe. The rapid increase in intensive management systems of poultry, pigs, cattle and fur-bearing animals has been the subject of heated debate in every European country. The publication of Ruth Harrison's book, Animal Machines, a quarter of a century ago, can now be seen as the starting point for the increasing demands for legislation to control what are seen to be new and unnecessarily restrictive ways of keeping farm animals. In the United Kingdom, as long ago as 1965, the Brambell Committee made recommendations that were largely ignored. Animal welfare societies increasingly called for legislation to control the situation. Society generally, on the other hand, welcomed the provision of cheap eggs, cheap poultry meat and relatively cheap dairy products.
Use of protected amino acids to increase duodenal amino acid supply in lactating dairy cows
Authors: Beever D E , Napper D J , Sloan B
Published: June 2019

Augmenting the supply of specific amino acids to pigs and poultry is straightforward cbinpared with ruminants where fermentation in the forestomach may reduce the proportion of the supplement which ultimately reaches the small intestine. Recently there have been several attempts to develop amino acid supplements which escape rumen degradation, thus optimising the increase in duodenal amino acid supply. The work reported in this study provides an in vivo assessment of one such product - namely lysine and methionine coated with a pH sensitive polymer.
The effects of sire type, company source, feeding regimen and sex on eating quality of pig meat
Authors: Warkup C C , Dilworth A W , Kempster A J , Wood J D
Published: June 2019

The introduction of new breeds, genetic progress in traditional breeds and the slaughter of entire males have helped reduce average P2 backfats by 0.5mm per year over the last 10 years. In the early 1980's, there was growing industry concern over the possible reduction in eating quality by the production of very lean pigs and entire males. The Meat and Livestock Commission's first Stotfold trial included an examination of these issues.
The effect of diet on skatole concentrations in the intestine and adipose tissue of growing pigs
Authors: Hawe S.H. , Walker N.
Published: June 2019

Microbial metabolism of dietary tryptophan in the gastro-intestinal tract results in the production of skatole and indole. These compounds, collectively classed as indoles, may be absorbed and deposited in carcass tissue and have been associated with taints especially in entire male pigs (Hansson et al., 1980). As indoles are readily absorbed over the entire tract in humans (Fordtran et al., 1964), it was suggested by Lundstrom et al. (1988) that diet may influence skatole production and hence levels in the carcass. The objectives of this study were to determine the sites of skatole production in the gastrointestinal tract and the effect of diet on production and carcass levels.
Rumen proteolysis of constituent proteins of soyabean meal
Authors: Newbold J.R. , Rust S.R.
Published: June 2019

Many feedstuffs consist of a variety of proteins which, differing in size and structure, may undergo proteolysis in the rumen at different rates. The conventional use of single, constant coefficients to describe the proportion of protein degraded in the rumen (e.g. 0.65 for soyabean meal) may, therefore, be inappropriate. Soyabeans contain two major storage proteins, β-conglycinin and glycinin. Two experiments were conducted to assess differences in rate of proteolysis between α and β sub-units of β-conglycinin (molecular weight approximately 66kD and 56kD, respectively) and acidic and basic sub-units of glycinin (approximately 36kD and 23kD, respectively).
The usefulness of commercial pig farms for research studies
Authors: English P R , Fowler V R , Roden J A
Published: June 2019

Harnessing the resources of commercial pig farms to augment research and development facilities provided by Universities, central Government funding and by commerce is not a new approach. The commercial farm sector, with appropriate deployment, provides a very useful resource. While these facilities can be most valuable in contributing to the overall R and D effort one must be aware of their actual and potential limitations.
The effect of protein content of the supplement on the response to level of supplementation with dairy cattle offered grass silage ad libitum
Authors: Mayne C. S.
Published: June 2019

Previous studies at this Institute have shown that there is an interaction between level of supplementary feeding and protein content in the supplement. For example, a given milk yield can be obtained by offering supplements of high crude protein content at much lower levels than would be required with conventional supplements. Furthermore, this approach enables a greater reliance on the forage component of the diet, particularly where high quality grass silage is available. The objective of the present large scale study was to determine milk production responses to supplements of differing protein content, given with high quality grass silage, and to examine effects on ration digestibility.

The experiment was carried out over a two year period, with a total of 168 autumn-calving British Friesian dairy cows. Supplements containing either 100, 220, 340 or 460 g crude protein (CP)/kg fresh weight were offered from day 14 of lactation. Each supplement was offered at four levels, with 9 animals per treatment.
The effects of feeding diets containing high levels of fibrous by-products during late pregnancy on sow performance
Authors: Edwards S A , Taylor A G
Published: June 2019

Many by-products available for feeding to pigs are high in fibre. The effects of such materials on feed in-take and killing-out percentage make them poorly suited for feeding to growing pigs, except at very low inclusion levels. These considerations are not limiting in the breeding sow, and the potential for utilising bulky by-products is consequently much greater. There may also be advantages for animal welfare and simplicity of management if diets containing such products can be fed ad libitum in loose housing systems.

This experiment was carried out to measure the effects of inclusion of very high levels of fibrous by-products in the diet of sows during late pregnancy on subsequent performance of the sow and litter.
Prediction of voluntary intake of grass silage by lactating cows
Authors: Rook A. J. , Gill M. , Willink R. D.
Published: June 2019

Prediction of voluntary food intake is Important in the formulation of rations for dairy cows. There are a number of prediction models which perform relatively well for diets based on dry forages but not for silage based diets (Neal, Thomas and Cobby, 1984). Prediction of intake of silage based diets is particularly important in the UK where 0.85 of the conserved forage fed to dairy cows is silage. A large and increasing proportion of herds are fed silage ad-libitum and concentrates at a flat rate. This study was an attempt to produce better prediction models for voluntary intake of silage by dairy cows under this feeding regime.
An alternative approach to the use of silage inoculants
Authors: Merry R J , Theodorou M K , Beever D E , Leemans D K , Thomas C
Published: June 2019

Most commercially available silage inoculants are supplied as freeze-dried preparations of lactic acid bacteria (LAB) which are rehydrated immediately prior to application to herbage (Wilkinson, 1989). One limitation of this approach is that rehydrated bacteria are likely to be less active initially than ‘freshly cultured’ (actively growing) cells. Thus an extended lag phase may precede the period of logarithmic growth of freeze-dried inoculants. From the above argument, it follows that freshly cultured bacteria may be preferable in order to enhance activity in the initial period of ensilage.

In two experiments, firstly the principle of using freshly cultured inoculants was examined in laboratory silos followed by a scale-up of the inoculant production process to investigate the practicability of using it in an on-farm system, and examining its effect on silage composition and cattle production response.
Sensory attributes of organic and conventional beef
Authors: Younie D. , Hamilton M. , Nevison I.
Published: June 2019

Awareness of food quality has increased considerably amongst consumers for a number of reasons. These include concern over agrochemioal residues and eating quality. Food produced to organic standards is claimed to be of intrinsically better quality than conventionally produced food. Apart from the likelihood of reduced agrochemical residues, it is also suggested that organic food tastes better. Livestock diets are known to influence the taste of meat and milk products (Younie et al 1988). The experiment described here was initiated to determine whether beef produced organically had different flavour characteristics from conventionally produced beef.

Beef samples were obtained from two groups of Hereford x Frieslan steers born in autumn 1987, reared within the framework of an 18 month beef system and finished in early 1989.
Livestock diversificaiton the potential for farming camelids in the united kingdom
Authors: Campbell Colin
Published: June 2019

The British government is encouraging livestock diversification and the production of those animal products which are still being imported. Currently most farm animal fibres such as mohair, cashmere and alpaca are imported with the result that there is a potential for developing production in the U.K. South American camelids can all be farmed for their fibre and present few nutritional or managemental problems. The llama is the largest of the four species with the male weighing about 116 kg. It produces coarse fibre of various colours. The alpaca is smaller than the llama, has short ears, a woolly face and a rounded rump. It averages 1 m in height and the male weighs 64 kg. There are two types of alpaca with different characteristics, the Huacaya and the Suri. Yields of 2.00 kg of good quality 18-30 micron fibre are normal. In South America the vicuna and the guanaco exist only in the wild state. Guanacos have shaggy coats of fine texture, usually chestnut borwn.
The effect of dietary concentration of added fat on the performance of growing pigs at equal energy intake
Authors: Patterson D C
Published: June 2019

Evidence has been found in growing broiler chickens that the presence of added fat in the diet can enhance the energy utilisation of the non-lipid portion of the diet due to an interaction between fat and the carbohydrate component of the diet (Mateos & Sell, 1980; 1981). Also, while it is known that a negative correlation exists between the degree of saturation of the fat and its digestibility in monogastric animals (Freeman, 1983), few studies have examined a range of degrees of saturation with growing pigs. The present study aimed to investigate the effects of both the concentration of added fat and the degree of saturation of the fat in the diet on the performance of growing pigs. The fats used in the study were beef tallow and soya oil and are regarded as relatively saturated and unsaturated fats respectively and the assumed digestible energy (DE). values for these fats were 32.1 and 36.0 HJ/kg respectively.
Estimation of carcass lean content in the revised EC Pig Grading Scheme
Authors: Cook G L , Kempster A J
Published: June 2019

A revised EC Pig Carcase Grading Scheme was introduced on 1 January 1989. It applies at all abattoirs slaughtering over 200 pigs a week. Carcasses are graded on the basis of -their estimated lean content. The estimate is made from prediction equations approved for use in each country and based on objective measurements, normally including subcutaneous fat depth, muscle thickness and carcase weight. Each carcass is placed in one of five (or optionally six) grades, the grades representing steps of 50g/kg in estimated lean content.
Evaluation of the performance of five exotic pig breeds under test station conditions in zimbabwe
Authors: Pathiraja N. , Mandisodza K. T.
Published: June 2019

Three British breeds, Large White, Landrace and Welsh are used widely in producing crossbred sows for commercial slaughter pig production in Zimbabwe. In most cases crossbred sows are mated either to Duroc or Hampshire to produce slaughter progeny. This study was undertaken to evaluate the performance of these five breeds under test station conditions.

The records for this study were obtained from the central test station. The data included 1513 centrally tested pigs over the five year period 1984-88. The traits analysed were daily gain (DG) g, food conversion ratio (FCR) between 35-86 kg, k backfat depth at 86 kg (BF) mm, conformation-score (CS) and leg-score (LS). The data for CS and LS were on a 50-point scale, taken at the end of the test. Animals were fed on a restricted scale during performance testing. The data were analysed by least-squares procedures. For all the traits fixed effects considered in the analysis were season, year, sex, breed, age at start of the test and interactions as appropriate. The season according to month at start of performance test was classified as cold (April-June), dry (July-September), early Summer (October-December) or late Summer (January-March).
Lifetime performance of pigs fed post-weaning diets of different levels of ideal protein
Authors: Kay R.M. , Miller B.V. , Bourne F.J. , Gibson J.
Published: June 2019

Both level of feeding and dietary composition have been demonstrated to influence bacterial colonisation and diarrhoea in the weaned pig. Specifically, Bertschinger et al (1979) demonstrated that diets low in protein and energy and high in fibre content could protect the weaned pig against challenge with live pathogenic E. coli. However, pig growth was so compromised that it proved to be unsatisfactory for commercial practice. Miller et al (1984) demonstrated that a diet in which the protein (casein) had been hydrolysed to constituent amino acids or peptides, thus markedly reducing its antigenicity, also could prevent post-weaning diarrhoea and minimise associated gut changes. They therefore, suggeted that one of the factors which may contribute to the aetiology of post-weaning diarrhoea is a transient hypersensitivity to dietary antigens prior to tolerance development.

The aim of this present work was to attempt to combine these two approaches yet achieve acceptable piglet performance, the long-term aim being to design weaner diets which effectively control post-weaning diarrhoea on commercial farms without resulting in the use of antibiotics either prophylactically or therapeutically.
A study of factors which influence the job satisfaction of stockpeople on commercial pig farms
Authors: Segundo R C , English P R , Burgess G , Edwards S A , MacPherson O , Russell P A , Shepherd J W , Dunne J
Published: June 2019

The role of stockmanship in relation to the wellbeing of farm animals has been emphasised in the UK Codes of Recommendations for the Welfare of Farm Livestock (MAFF, 1983). Moreover, previous research work has demonstrated important effects of good and bad stockmanship not only on welfare but also on growth, lactational and reproductive performance of pigs and other farm livestock (Hemsworth et al, 1987). There is a need, therefore, to establish the factors which motivate and demotivate stockpeople since the degree of job satisfaction is likely to have a considerable influence on the attitude and performance of stockpeople and on their empathy with the animals in their care. With this objective in mind, a questionnaire was designed to investigate the aspects which could have an influence on the job satisfaction of the stockpeople involved in pig production.
A Critical Evaluation of Culling Policy in a Commercial Herd of Sows
Authors: Dunne J H , English P R , MacPherson O , Roden J A , Segundo R C
Published: June 2019

Pig producers must continuously strive for improved productivity and efficiency in order to remain competitive. The effect of sow culling rate on overall herd productivity is well documented in the scientific literature (Kroes and Van Male 1979, Dagom and Aumaitre 1979, Dujkhuizen 1986). Recent indications, however, are that there is still much room for improvement in the efficiency of sow culling policy. The objectives of this work were a) to determine the incidence of and reasons for culling in a modern 800 sow commercial pig farm using Large White x Landrace sows, and b) to attempt to develop a more objective basis for culling on poor litter performance (essentially low numbers born).
The influence of inclusion of a probiotic in the diet on the development of enzyme activity in the small intestine of the pig
Authors: Collington G.K. , Parker D.S. , Armstrong D.G. , Ellis M.
Published: June 2019

The objective of the present study was to investigate the development of hydrolase enzyme activity at six sites along the small intestine of the pig before and after weaning and the influence inclusion of a probiotic preparation had upon this. The enzymes studied lactase, dipeptidase and tripeptidase are primarily associated with the brush border of the enterocyte cell and expression of hydrolase activity has been shown to be affected by manipulation of the microbial population of the gut.
The application of electronics to the study of animal behaviour
Authors: Lawrence A B
Published: June 2019

Animal behaviour is increasingly seen as a useful tool in animal production. However, behavioural observations are time costly, and it is difficult to ensure precision and repeatability of measurement.

An alternative to observation is to use electronics to automatically record behaviour and two such applications are illustrated:

The first system developed at Edinburgh records drinker and chain-related activity, two common abnormal behaviours in pregnant sows. Water flow meters record drinker use. Chain behaviour is monitored by supplying each sow with a vertically hanging chain to which is attached piezo-electric ‘wire’. Electrical activity is generated from the flow meter or the piezo-electric wire as the sow manipulates the drinker or the chain, and is read by a micro-computer at 60 seconds intervals. The system estimates water use and circadian patterns of drinker and chain activity for 16 sows. Applications include recording the development of these two behaviours in response to variations in variables such as feeding regime.
Electronic live animal and carcass identification systems
Authors: Slader R.W. , Gregory A.M.S.
Published: June 2019

Unique and secure identification of livestock from birth through to the carcass in the abattoir will become a key feature in many areas of livestock production: disease eradication; quality assurance schemes; pedigree breeding; and producer feedback from abattoirs. There have been many attempts at adapting traditional methods of animal identification to provide a measure of automatic recognition. None has been as successful as the application of radio frequency transponders which transmit a unique code when triggered by a suitable reader.
Survey of the state of the art of computerisation in British meat plants and an assessment of training requirements
Authors: Porter S J , Kempster A J , Sains A G
Published: June 2019

The meat industry needs a skilled workforce to meet the challenges of the 1990's. The need is particularly acute in computing and information technology (IT) because people with the necessary skills are becoming notoriously difficult to find, even for the most technologically advanced and high-salaried industries. The expected fall by 20% in the number of young people in the national labour force between now and 1995 will exacerbate these difficulties, as will the poor perception that potential employees have of the meat industry.
Automatic recording of individual voluntary feed intake in group housed pigs
Authors: Brown A.N.R. , van der Steen H.A.M.
Published: June 2019

Genetic improvement of pigs relies heavily on improving feed conversion and controlling feed intake capacity. For this purpose it is vital to measure feed intake of individual pigs. Traditionally this has been achieved by keeping pigs singly or in sib-pairs in small pens. Such facilities are expensive to build and are difficult to design to cater adequately for pigs over a wide range of weights and at low stocking density. Keeping animals in small pens is less than satisfactory from a welfare aspect.
Electronics in genetic improvement of pigs
Authors: Webb A.J. , Bampton P.R. , Smith S. , Close S. P.
Published: June 2019

Past genetic improvement programmes have concentrated mainly on lean growth. They have relied on a few simple measurements of growth rate, food intake and ultrasonic backfat, which were laborious to record, check and process. Now there is increasing concern to improve, or at least avoid undesirable correlated changes in, eating quality, distribution of lean, and reproduction.

New electronic techniques offer the opportunity to record additional traits, with lower costs and faster data processing. This paper reviews the likely impact of electronics on the rate and nature of genetic improvement in pigs.
The effect of inclusion of virginiamycin in feed on glucose and alanine transport by intestinal brush border membrane vesicles of sheep
Authors: Parker D.S. , Tapper H. , Mason H. , Tuer H.
Published: June 2019

Manipulation of the bacterial population of the intestine has been shown to result in changes in the structure and function of mucosal tissues. The objective of the present experiment was to investigate the effect of inclusion of a non-therapeutic antibiotic, virginiamycin, in the diet of sheep on the activity of the Na* -dependant transport of glucose and alanine by enterocyte cells. These transport mechanisms can be studied by isolation of brush border membrane vesicles following sub-cellular fractionation of the mucosal tissues.

Tissue was obtained from two separate growth trials in which the effect of inclusion of virginiamycin on lamb growth was being studied. In Trial 1 (glucose studies) the animals had been fed a concentrate diet plus hay ad libitum and virginiamycin was included at 100 ppm in the treatment group. In Trial 2 (alanine studies) the sheep were fed a concentrate diet with virginiamycin included at 50 ppm in the treatment group.
Effects on animal performance of a fat concentrate in diets for growing fattening bulls
Authors: Istasse L. , Clinquart A. , Dufrasne I. , Gabriel A. , Van Eenaeme C. , Bienfait J.M.
Published: June 2019

Growing fattening bulls in Belgium require diets high in concentrate and low in roughages in order to achieve large live weight gains and high quality carcasses. Sugar beet pulp is usually incorporated at a high inclusion rate in fattening diets. It is supplemented with cereals, by-products like wheat bran or glutenfeed and protein supplements very often of vegetable origin. The fat content of such diet is low. Over the recent years, there has been an increasing pressure from the industry to incorporate fat in fattening diets. Each company produces its own fat concentrate. They are blends of various origins. The present experiments were carried out to assess the effects, on animal performances, of soya oil and linseed, two fat concentrates of vegetable origin incorporated in fattening diets.
The effects of supplements containing different carbohydrate sources on milk production in cows receiving a hay-based diet
Authors: Martin P.A. , Chamberlain D.G. , Robertson S.
Published: June 2019

There are well established differences in the digestion characteristics of the carbohydrate sources available for inclusion in rations for dairy cows, but the implications of these differences for milk production remain poorly defined. The experiment reported here was conducted to compare 4 concentrates containing contrasting carbohydrate types, namely sources of readily-fermentable starch (barley), of sugar, of starch that is fermented relatively slowly in the rumen such that some is absorbed as glucose from the small intestine (maize) and of sugar and digestible fibre (citrus pulp). Given the advantages of dietary inclusion of appropriate fats as a means of increasing the energy density of the ration and/or of producing ‘less-saturated’ milk fat, and the likelihood that responses to high-fat diets would be modified by carbohydrate type, the different carbohydrate sources were compared in concentrates containing a high proportion of fat (16% on a fresh weight basis) as calcium salts of long-chain fatty acids.
Effect of fishmeal supplementation on in-vitro adipose tissue metabolism in young cattle fed silage
Authors: Walsh A , Beever D E , Gill M
Published: June 2019

Acetate conversion to fatty acids in adipose tissue requires NADPH which, in ruminants, is generated mainly by the oxidation of glucose via the pentose phosphate pathway and from acetate via the isocitrate cycle. In ruminants negligible amounts of glucose are absorbed from the alimentary tract and glucose is synthesized from propionic acid and gluconeogenic amino acids in the liver. Silage diets are high in lipogenic precursors (acetate and butyrate) but characterized by low amounts of gluconeogenic precursors. This should give high levels of fat deposition, but the limited supply of glucose or its precursors may still result in an excess of acetate production relative to its utilization. Fishmeal (FM) supplementation of silage diets tends to stimulate silage intake and liveweight gain probably due to an increased protein supply and improved energy/protein imbalances in the rumen, but its effect on lipid metabolism has not been fully elucidated.
Effect of dietary inclusion level of low glucosinolate rapeseed on growing pig performance
Authors: Davis M. , Ellis M. , Smithard R.R.
Published: June 2019

Current suggestions for the upper limit for the total gucosinolate content of oilseed rape are around 20 μmol/g of seed, which corresponds to a level in the de-fatted meal of approximately 33 μ mol/g. Information about the suitability of this material for incorporation in growing pig diets is required by the UK feed industry. When attempting to provide the required information the presence of factors such as tannins, sinapine and phytate in rapeseed meal should be considered, as must the high (≈ 120 g/kg) fibre content of the material. This experiment was designed to examine growing pig performance from 30 to 75 kg liveweight when fed diets containing increasing levels of rapeseed meal at both fixed and increasing glucosinolate contents.
The effect of dietary protein:energy ratio during food restriction on the size of the digestive tract and subsequent growth of lambs
Authors: Mantecon A.R. , Iason G.R. , Smith A.D.M.
Published: June 2019

During both food restriction and subsequent re-alimentation of sheep, the proportion of empty body weight formed by the gastro-intestinal components has been shown to change (Winter, Tulloh and Murray, 1976; Murray and Slezacek, 1988). The extent and nature of compensatory growth depends on the composition of the diet during restriction (Wilson and Osbourn, 1960). This study investigates the effect of rumen undegradable protein in the diet, during food restriction, on these processes. The hypotheses tested were that the protein:energy ratio of the diet during restriction to constant liveweight (LW) influences the relative proportions of the components of the digestive tract and its overall size as a proportion of empty body weight (EBW) a) during restriction and b) during subsequent growth on realimentation.
Effect of altrenogest on litter size in primiparous sows
Authors: Baker D.J. , Peters A.R. , Gettinby G.
Published: June 2019

Aitrenogest (17 α -allyl-17-hydroxyestra-4,9,11-trien-3-one; Regumate Porcine; Hoechst Animal Health) is a synthetic progestagen which has been used to control and synchronise the ovarian cycle particularly in cyclic gilts. However progestagens have also been used in various species to induce and synchronise the first ovulation post partum. The present study was undertaken to determine the effect of altrenogest treatment on the reproductive performance of primiparous sows.
The effect of water-spraying bacon weight pigs in lairage on behaviour and carcase quality
Authors: Weeding C.M. , Guise H.J. , Hunter E.J. , Penny R.H.C.
Published: June 2019

Handling pigs with care before slaughter is beneficial for both animal welfare and meat quality. Water showering pigs in lalrage prior to slaughter is considered to calm pigs, improve meat quality and reduce slaughter line contamination (Logtestijn, Corstiaensen and Kruijf, 1977; Smulders, Romme, Kruijf, Eikelenboom and Corstiaensen, 1982). The objective of this experiment was to investigate whether water-spraying pigs, in the lairage of a commercial abattoir, reduced the amount of fighting and if it improved meat quality.
Metabolic and endocrine changes in the sow during lactation
Authors: Close W.H. , Mullan B.P. , Sharpe C.E. , Buttle H.L.
Published: June 2019

During lactation sows are often unable to consume sufficient feed to meet their metabolic needs and they must mobilise their body reserves to compensate for the nutrient deficit. It is generally recognised that this loss of body weight and body condition may influence subsequent reproductive performance but it is unclear what endocrine signals link the nutritional and reproductive states of the sow. The present experiments were, therefore, designed in an attempt to understand how changes in the nutritional and metabolic status of the sow during lactation influences post-weaning reproductive performance.
The influence of allyl-trenbolone on the steroid hormone concentrations of multiparous sows in lactation and after weaning
Authors: Costa A , Varley M A
Published: June 2019

Previous work has shown that although the ovaries of multiparous sows are quiescent throughout lactation (McDonald, 1980; Edwards, 1982) there are episodes of oestrogen activity in the peripheral circulation which are both highly variable and at very high concentrations (Varley and Foxcroft, 1989). The suspicion is that the source of this oestrogen is the adrenal gland although it is also possible that body fat stores are capable of being involved in this. Any treatment causing adrenal regression should therefore reduce the incidence of oestrogen episodes in the peripheral circulation.

An experiment was therefore carried out at Leeds University to investigate the use of an orally active progestogen, allyl-trenbolone, which is routinely used in gilts and sows for the control of oestrous cycles, on the steroid hormone status and reproduction in multiparous sows.
Effects of processing on chemical characteristics and nutritive value of cereals
Authors: Champ M. , Delort-Laval J.
Published: June 2019

A large variety of processes - physical, chemical and/or biotechnological - is currently applied to cereals (Table 1).

Among physical treatments, grinding is the most comnon ; it does not modify the chemical characteristics of the grains but improves the accessibility of the enzymes of the gut to their substrates by disrupting endosperm and aleuron cell walls. Thus, milling exposes the interior parts of the grain to the digestive enzymes. Some physical processing of barley grain, such as rolling, is necessary to give optimum digestion of the nutrients by cattle (ORSKOV, 1976). This treatment, applied to barley, appears to be beneficial for young species (KREFT and BOYLES, 1989). Pigs eat whole or very coarsely milled grain reluctantly (MAXWELL et al., 1970) and utilize whole barley poorly (LAWRENCE, 1970). For this reason, barley grain is commonly milled before feeding. Grinding of maize using a roller mill does not modify average daily gain, feed intake, feed conversion and fattening time of pigs. However, sensory evaluation tests, meat from control pigs fed untreated maize is preferred to meat from pigs given rolled maize (ITOH et al., 1986). However, finely ground barley causes a strong increase in the frequency of oesophagogastric lesions whereas diets countaining coarsely ground barley or crushed oats caused few lesions. Balance trials on lamb indicate that whole maize have more digestible, metabolizable and net energy than ground maize (BONSEMBIANTEE et al., 1988).
The Effect of tannins on chicks using field bean lines (vicia faba.) isogenic except for tannin content
Authors: Wareham C.N. , Wiseman J. , D.J.A. Cole
Published: June 2019

Tannins are phenolic compounds which possess antinutritional properties. Studies to assess the effects of tannins have either used bean cultivars containing differing levels of tannins (Jansman, Huisman and van der Poel, 1989) or tannin extracts (Marquardt, Ward, Campbell and Cransfield, 1977). This experiment evaluated the effect of tannins on the utilization of dietary energy and nitrogen by broiler chicks using two lines of field beans which were isogenic except for tannin content. Chicks were used because of their sensitivity to nutritional changes in the diet.
Autoregressive models for the prediction of constituents of milk in dairy cows
Authors: Rook A. J.
Published: June 2019

Milk producers in the UK are paid according to their production of milk fat, protein and lactose and are also subject to a production quota which includes an element restricting fat production. The ability to predict the production of milk solids consequent on the feed inputs and animal state is therefore important. Results reported previously (Rook, Sutton and France, 1990) showed that multiple regressions of milk constituent yields on feed variables and animal characteristics such as parity and postcalving liveweight fitted poorly, with R2 ranging from 0.35 for lactose yield to 0.52 for protein yield. In practice, however, previous yields are often available and can be used to improve the fit of these empirical models. This study investigated the use of models including previous yields.
Genetic manipulation of plants - the new opportunities
Authors: Davies D. R.
Published: June 2019

The recently developed technologies of genetic engineering offer the plant scientist not only a number of opportunities for introducing valuable novel characteristics into some of our crop plants but also provide for the first time the means to analyse and dissect some of the complexities of plant development and metabolism, and which will ultimately lead to even greater contributions to plant science.

At present the technology is still in an early phase of development. Methods of isolating particular genes and regulatory sequences are accelerating rapidly, as are the means of modifying them prior to their reintroduction into plants; the ability to culture cells and tissues in vitro are well established for a great number of species. Introducing the genes into plants cells is relatively easy for some species but remains very difficult as yet for others, including some of our most important crop plants; regenerating whole plants from cultured cells and tissues is similarly easy for some but difficult for others. However even at this early stage there are some remarkable achievements; the production of herbicide resistant plants by incorporating genes either from bacteria or from unrelated plants is one. Resistance to particular insects has been achieved by again incorporating a gene from a bacterium which codes for a toxin or one from a plant which codes for a naturally occurring compound toxic to insects. An achievement which may have even greater potential is that of the production of virus resistant plants; this is achieved by incorporating a part of the virus’ own genetic information into the plant. These achievements are already nearing commercial exploitation in some instances.
The estimation of genetic merit
Authors: Naomi Wray
Published: June 2019

The objective of any livestock breeder is the identification of stock of superior genetic merit with respect to some goal for the production of future generations; their objective is the estimation of genetic merit. Traditional breeders achieve this simply by visual appraisal. Some breeders have realised the value of collection of performance records to make the assessment more objective. The animal’s performance record however results not only from the animal’s genetic make-up but also from the management and other non-genetic factors (age of dam, age of measurements) that it has experienced. Best Linear Unbiased Prediction (BLUP) is a method to estimate genetic merit (or breeding values) of animals. BLUP is universally regarded as the best method available to us to predict genetic merit of animals when performance records have been collected In a variety of herd, year, season and management environments. Considerable investment of time and money Is made in the organisation of unique animal identification and collection of records. It is therefore appropriate that maximum use is made of those records in the accurate prediction of genetic merit of individual animals.
Maternal: infant interactions and growth in lambs
Authors: J.M Bassett
Published: June 2019

Hormones play a vital role in promoting growth and in re-ordering metabolic priorities among tissues in a wide variety of physiological situations important to animal production. During pregnancy and lactation, however, the hormonal requirements for growth promotion in the developing infant seem diametrically opposed to those necessary within the mother for support of pregnancy and later for the provision of milk to the suckling young. Fetal endocrine autonomy clearly plays an essential role in protecting prenatal development. Despite this, fetal metabolism cannot be isolated altogether from that of the mother because of the need for maintained nutrient transfer to the conceptus. Indeed, hormones secreted by the fetal placenta into the maternal circulation appear to play important roles in manipulating maternal metabolism to favour transfer of metabolic substrates such as glucose to the conceptus. Similarly, alterations in the secretion of growth hormone during lactation have been considered to play an important homeorhetic role favouring transfer of substrate to the mammary gland for milk synthesis. However, many aspects of these adaptive changes remain uncertain.
Nutrition: reproduction interactions in cows
Authors: Wright I.A. , Peters A.R.
Published: June 2019

In any cattle production system, reproductive performance is of central importance. The output from beef cow systems is calves, while lactation in the dairy cow is only achieved following parturition. On a world basis, the major cause of poor reproductive performance is inadequate nutrition, and in most cases this is represented by an inadequate energy supply, although in specific circumstances particular vitamin, mineral or disease problems can occur. This review considers how nutrition, and in particular energy nutrition may act via the endocrine system to influence reproductive performance in cows. The paper will consider the post-partum anoestrous period, fertilization and embryo mortality.
BSE and scrapie in perspective
Authors: Fraser Hugh
Published: June 2019

Scrapie-like diseases occur in sheep, goats, cattle, and other ruminants, in mink, and in man. An identical disease has now been seen in cats. There are no in vitro laboratory tests of infection which thus can only me recognised clinically, neuropathologically, with tedious animal transmissions, and by finding an altered host protein, called PrP, electrophoretically or ultrastructurally. There is no immunity in these diseases, due to an absence of infection-specific antigens, Assays of infection depend on incubation period measurements in mice infected intracerebrally with serial dilutions of infective sources. Dilution of different strains or isolates, or of single strains in different host genotypes, or using different routes of infection, result in distinct dose-response curves (incubation period/infecting dose).
Influence of acetylation on peptide breakdown by microorganisms from the sheep rumen
Authors: Wallace R.J.
Published: June 2019

Protein is broken down by rumen microorganisms via peptides and amino acids to produce ammonia at rates which frequently exceed microbial requirements for N. Much of the ammonia-N formed in this way is eventually excreted as urea. If any of the steps in the degradation sequence could be inhibited, excessive ammonia production would be reduced. More protein, peptides or amino acids would escape fermentation in the rumen, thereby improving the protein nutrition of the host animal.

The breakdown of peptides to amino acids is a central part of the degradation sequence. The main enzymic mechanism by which peptides are hydrolysed in the rumen is a bacterial dipeptidyl aminopeptidase, which cleaves dipeptides from the N-terminus of the peptide chain (Wallace & McKain, 1990). Little carboxypeptidase activity appears to be present. The present experiments were undertaken to find out to what extent blocking the N-terminus of peptides enables them to survive degradation in rumen fluid, and to determine which peptides can be protected in this way.
Use of fishmeal to reduce lamb weight loss on dietary change
Authors: Vipond J E , FitzSimons J , Brown H , G Horgan
Published: June 2019

Year round production of lamb Is constrained by the seasonal breeding of the ewe with a shortage of lambs onto the UK market In the first two quarters of the year leading to enhanced prices in this period. Lambs sold onto this market in the past have received little variable premium due to strong market prices. Transfer of support from variable premiums to headage payments in 1992 should encourage farmers to spread the marketing period of lamb into the period of shortage. New systems of storing lamb have been developed involving a housed store period from September to November on a straw based diet followed by turnout to swedes for finishing. Large liveweight loss on adjustment to the straw based diet has been a constraint In previous trials (Dingwall et al, 1989). Previous work on slimming diets for sheep (Vipond et al, 1989) suggests fishmeal supplementation during the changeover period could reduce weight loss and improve performance.
In vivo nutritional evaluation and feeding value of silage made from extensive pastures containing wildflowers and herbs
Authors: Fisher G E J , Offer N W
Published: June 2019

With the trend in agriculture to more extensive systems of production it is likely that less productive grasslands with lower inputs of fertilizer nitrogen will be used. However, there is a need to marry conservation orientated policies with profitable farming. It is therefore necessary to study the nutritional quality of forage from extensive pastures which will be used for animal production. The objectives of this experiment were to measure the digestibility in vivo of silages made from extensive pastures containing grasses, clovers, wildflowers and herbs and to investigate the feeding value of big bale silage from these pastures for feeding dairy heifer replacements for calving at two years of age.
The effect of a plasma derived immunoglobulin supplement on the survival and growth of neonatal piglets
Authors: Pullar R A , Varley M A , Anderton D J
Published: June 2019

Neonatal mortality represents a major loss of production efficiency for herds throughout the world and despite research and development work spanning many years the losses are still not tolerable either in economic terms or in terms of animal welfare. In the United Kingdom where producers are amongst the very best, the Meat and Livestock Commission estimate that pre-weaning mortality nationally is of the order of 12.8% of all piglets born alive (MLC, 1984).

The causes of death are well documented (Spicer et al 1986) but overlying, starvation, chilling and pathological problems are principal components. Central to all of these factors may be the events occurring within the first hours of a piglets life and those animals which are first born which suckle quickly and effectively have a high probability of survival.

Conversely, those piglets which are later born and which are also smaller than the average for the litter may be at a severe disadvantage because of the competitive environment around the udder of the sow after parturition. Modern hybrid sows also vary widely in their ability to produce colostrum (Varley,1984)
Relationship between behavioural response to amphetamine and propensity to develop stereotypic behaviour in pigs
Authors: Terlouw E M C , Lawrence A B , lllius A W
Published: June 2019

The dopamine systems In the brain are strongly involved in motor activity. Pharmacological stimulation of brain dopamine systems with dopamine agonists initially results in increased levels of motor activity that with increasing doses become more stereotyped in form. It has been suggested that in tethered sows, stereotypies develop because chronic environmental stress produces activation of brain dopamine systems (Dantzer, 1986). Furthermore, differences In the sensitivity of brain dopamine systems may form the basis of the large individual variation found in level of stereotypies (Segal and Kuczenski, 1987). Manipulation of the chain forms the major category of stereotypic behaviour during long term tethering. In addition, many pigs develop excessive drinking (Terlouw et al., in press). The present study investigated whether female nulliparous pigs differed in their response to a standard dose of amphetamine and whether this response is correlated to the amount of chain activity and drinking that developed during subsequent long term tethering.
Intake and behaviour of cattle at different feed barriers
Authors: Petchey A M , Abdulkader Jemal
Published: June 2019

Feed barriers and mangers form an integral part of a cattle housing system. Their role is to prevent the animals’ wasting feed by scattering it or by walking and defecating over it. Feed barriers generally effect a better distribution of feed and should allow individuals adequate and ready access. Often they have a dual role and act as the side of a pen. These functions are often achieved with some regard to several managerial objectives; simplicity of feed distribution, labour economy, the regulation of excessive animal activity, minimal feed wastage and promotion of animal comfort.

Time spent at the feed barrier depends on the feedstuff, the rate of eating by the animal, space allocation, and the accessibility of the feed. Depending on the feed barrier design the animal may need to exert some force to reach the food. Injuries arise in those situations where large forces are exerted against the barrier and/or accommodating postures (ie kneeling or other) are adopted to reach the food. In extreme cases intake may be restricted. Thus, to assure maximum intake and minimise injuries the feed must be within the easy reach of the animal. Two trials with Friesian heifers compared the performance of 4 types of feed barrier.