産業動物の飼育への配慮の必要性
The Importance of Greater Consideration for Farmed Animals
佐藤衆介 東北大学大学院農学研究科 教授
Shusuke SATO Professor, Graduate School of Agricultural Science, Tohoku University
Thank you all for taking part in thispromote anything that causes them to feel positive

workshop on the Welfare andemotions as much as possible. Thatʼs the basic idea.

Management of Farmed Animals.

Since both these positive and negative aspects are

To d a y, I w o u l d l i k e u s t o s t u d yemotions, they cannot be measured directly. So how

together about the future of the

can we measure them? Some people try to evaluate

welfare and management of domestic

domestic animalsʼ emotional responses by checking

animals such as livestock.

how they avoid, approach, or run away from certain
things, etc.

To begin, I will talk about why I believe we have to pay
greater consideration to the welfare of domestic

The second thing is the physical environment in whichanimals, and I will also touch upon the sensitivity andfarm animals are raised. This should be designed in athe cognitive abilities of domestic animals that I believe

way that minimizes the animalsʼ stress as far as possible.

should form the basis of animal welfare. How then do

Stress can be measured by physiological changes or by

we develop this basis for so-called domestic animalchanges in hormone levels.

welfare? I will examine this question using the examples
of cows, pigs and chickens. Later on, Mr. Kuwajima, theThe third thing is to pay consideration to the natural

Products General Manager of Pal Meat, will talk about

impulses of animals. It seems that animals wish towhether or not welfare-conscious based raising of

behave in certain ways. Therefore, we compare thedomestic animals can be realized in practice. After that,behavior of domestic animals with that of animals living

we will discuss the future of the welfare andnaturally in the wild, and we watch the behavior ofmanagement of domestic animals together. That is thedomestic animals when their activities are controlled.

basic plan for todayʼs workshop.

While doing that, we pay consideration to ﬁnding ways
to allow these animals to behave more naturally.

Firstly, I would like to talk about the need forconsideration and to explain something about the

Next, I will introduce several examples of what is going

sensitivity and the high levels of cognitive ability

on emotionally with domestic animals using, as andisplayed by some domestic animals.

index, their actions such as running away from orcoming close to certain things. This can serve to indicate

In Europe, where the earliest discussions regarding

the degree of fear, etc., that they feel.

what should be considered in the care of domestic
animals began, it was agreed that we must consider

One example is a test that was devised by Prof. Kosako

three main things.

of the National Institute of Livestock and Grassland
Science. This is a test conducted on cows. A cow is put

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The first is emotion. It is considered that domestic

into a cowshed and a person also remains in the shed

animals do undoubtedly experience negative emotions

keeping still. Then we measure the distance between

or feelings such as pain and fear. Accordingly, we should

the person and the cow. Next, the person approaches

try to eliminate the causes of such emotions as far as

the cow and we note the distance at which the cow

possible. Likewise they also experience positive

starts moving away when the person approaches. We

emotions, such as comfort and joy, so we should try tomeasure this distance for both of these tests.

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産業動物の福祉と経営

We must ask what kind of treatment people gave thislevel of cortisol, which is a well-known stress hormone,

cow in the past? In this case, people made contact withwas higher when the cows were fed from the feeder.

the cow when it was a calf for 20 minutes per day for

Also, the level of oxytocin, a hormone released when

the first three days following its birth. This was an

the animals are comfortable, was higher when the cows

experiment to see how much the running distancewere allowed to feed by grazing on growing grass.

would change if new born calves were exposed to thisPhysiological changes occur depending on whether

degree of human contact. Among many species ofcows graze on growing grass or are fed cut grass from aanimals, infants aged about three days tend to be very

feeder. By taking these things as indices, we are asking

receptive. The first three days after birth is a period

questions about what the cows are thinking, and wewhen a calf has to establish a relationship with its

ourselves are thinking about the environment in which

mother, so calves of this age tend to be very sensitivedomestic animals are raised and kept.

by necessity.
This graph in my slide illustrates the results of research
Looking at the results, in a situation with no diﬀerences

performed on cattle in Canada by Rushen et al. In thefrom the previous experiment, when people try toexperiment, a ʻrough personʼ lightly struck at a cow witha p p r o a c h a c o w, i t i s f o u n d t h a t t h e y c a n g e t

a dehorning scoop whenever the animal came close,signiﬁcantly closer to those cows that were exposed towhile a ʻkind personʼ stroked the cow whenever it camehuman contact for 20 minutes per day for the ﬁrst threeclose. The cows were treated this way for five days.

days after birth. From this experiment, we can see that aThen, during the following week, a third person milked

cowʼs fear of humans can be eliminated by suchthe cow. The researchers measured the volume of milk

contact.

produced and the animalʼs heart rate. Coming back to
the person who behaved roughly toward the cow andMy next slide shows a test that was performed by post-

the person who was kind to cow the previous week,

graduate students at my own Tohoku University. We

what would happen if these people were to come inhave a livestock barn here. The researchers made aduring the milking? In fact, when the rough person

straight aisle running through it. Then they made acame into the room, the cowʼs milk production volume

grazing area right at the back. On one side of the

dropped signiﬁcantly. Even if the cow was milked aftergrazing area grass was growing. On the other side all

being injected with oxytocin a lot of milk still remained

the grass had been cut and put into an installed feeder.

in the cowʼs breast with the rough person was present.

What the researchers wanted to ﬁnd out was how fast

As for the heart rate, this also changed simply due tothe cowsʼ approach speed to their food would be. Thatthe presence of the person who treated the cow

is what they tested. The result was that when the cows

roughly for five days during the previous week. It

walked to the place where grass was growing, they

became very high. This result shows that domestic

moved signiﬁcantly faster. Conversely, when they wereanimals have sufficient cognitive ability to be able tofed raw grass from the same area that had been cut andremember how they have been treated and by whom.

placed in a feeder, they moved slower. This was one of

My graph shows that the best milking result was

the findings. One side has some grass growing, whileachieved when nobody came in during the milking.

the other side has the same grass placed in a feeder.
Even environmental diﬀerences of this degree produced

Many kinds of odd behavior can be observed ina different reaction in the cows. This means that thedomesticated animals. In zoos, an elephant shakes its

cows are engaging in complex cognition.

body from side to side. In the case of domestic animals,
pigs nibble other pigsʼ tales, chickens peck other

Next, the researchers allowed the cows to stay in thechickens, and calves suck other calvesʼ umbilical cords.

feeding area for 10 minutes. After that, the cowsʼ

Also, cows curl their tongues round in this way. Such

hormone levels were measured. It was found that theirrational behavior is common and it presents problems.

Workshop Ⅲ Welfare and Management of Farmed Animals

13For example, the behavior itself wastes energy andthem the students who were conducting thetime, and the welfare of the nibbled individuals is

experiment and the keepers who usually took care of

impaired. Chicken wings that are pecked may bethem. We performed this experiment on Japanese Black

injured. It is known that these kinds of behavior occur

Cows. These animals were not normally kept alone but

due to the restraint of strongly motivated instinctive

were kept as part of a group of several cows. We

behavior. They are known as ʻdisplacement behaviorʼ or

showed them the faces of their companions too. Then

ʻredirected behaviorʼ. By taking these things as an index,

we measured the number of seconds the cows looked

we try to analyze what domestic animals want to do.

at these pictures when each picture was presented for a

Domestic animals have rather simple minds so theirthree-minute period. The results were arranged in orderactual behavior can be changed significantly byof length of time from long to short. What the cows

suppressing their instinctive behavior.

looked at for the longest time were the photos of theircompanions kept in the same barn. This was followed

The next point I want to talk about is what sort ofby their regular keepersʼ faces and then by the faces ofsociety do domestic animals build? In this summary, I

the students. This result indicates that cows remember

have written about social behavior, but when I wasfaces. Cows have a high level of cognitive ability, so theymaking my slides, I noticed that the concept of society

can remember faces easily and they can continue tois rather diﬃcult to talk about, so I changed the theme

recall them for several years.

to “How domestic animals recognize their associates.”
Next, letʼs move on to a socially related subject. It turns
My slide shows an experiment that was conducted inout that cows exhibit caring behavior towards otherKendrick, England. You can see diﬀerences among thecows, such as licking their bodies. This is a survey aimed

faces of the sheep. In this experiment, sheep wereat trying to ﬁnd out which other cows they perform thistaught that food appears when they push a button

behavior on. While one cow is licking another, the heart

placed under a face. The sheep were made to learn thisrate of the cow being licked drops. Something similar

over the course of a week, and the accuracy of theirhappens in the case of humans too. When we have apushing is shown accordingly. The sheep learned up to

strong sense of security, our heart rate tends to drop. So

a certain level. It was an experiment that attempted tofrom this, we can assume that cows probably get ameasure how many days sheep can remember what

feeling of peace and security from being licked.

they have learned. Testing was carried out over various
periods, namely, from 75 days to 200 days, from 200

We conducted a survey of which other cows the cows

days to 400 days, from 400 days to 600 days, and fromperform their licking behavior on. As a result, we

600 days to 800 days after learning, to ascertain whether

ascertained that the most important factor is notor not the sheep could still recognize the sheep facewhether the receiving animal is strong or weak at

picture or not. For each time period, the accuracy rate

fighting - we could detect no differences in terms of

was found to have dropped a little, but the experimentﬁghting ability - but the diﬀerence in the two animalsʼ

established that sheep could remember what to dobirthdates. The important factors were that the twomore than 50% of the time in all of the periods. So

cows were born at about the same period and they

sheep have some rather amazing cognitive abilities.

shared a very long period of cohabitation. Also, cowsthat were blood relations tended to lick each other a lot.

This is an experiment that our team performed. We

This signiﬁes that cows possess the ability to recognize

installed a camera so that we could watch domestic

such things as well.

animals and we measured the number of seconds that14

they continued to look at diﬀerent objects. We showedThis next experiment was put together by Mr. Takeda.

the animals a picture of a sheep face, a goat face, as well

We wanted to find out if there are differences in how

as a dog, a giraﬀe, a horse, a cow, etc. And we showed

cows react when startled, depending on the

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産業動物の福祉と経営

environment they are in. The experiment waseating. My slide shows the situation for companions

conducted with two cows that were acquainted, withand the situation for exercise. When the button isanother two cows not acquainted, and with five cows

pressed their exercise area is increased, and in the casethat were all acquainted with each other. Theof the other button, when the number of required

experiment was aimed at discovering whether or not,pressings is increased gradually, their reaction drops. Itʼswhen we showed them something that startles cows, it

as if they are saying that they donʼt need to go or they

was helpful for them to be with their companions.

donʼt need a wider area. In the case of the button theypress in order to meet their companions, although the

For the experiment the cows were strongly startled byreaction is not as strong as in the case of the food

dropping a bucket from the ceiling. Then their heart

button, the reaction drops off less sharply than in therates were measured. Also, the researcher createdcase of the exercise area button. This experiment shows

conﬂict situations such as showing food to the cows butthat pigs are more motivated to meet their companions

not allowing them to eat it.

than to obtain a wider exercise area.

In both cases, when the cows were acquainted with

There is a quotation from a book written by aneach other, their average heart rates remained low, andAustralian researcher named Hemsworth. The names ofthis effect was particularly pronounced when five

many researchers are noted. They performed

acquainted cows were together. So, sensitivity to stressexperiments on pigs to investigate somatic growth andis reduced when cows are together with their

puberty, age of attaining sexual maturity, conception

companions.

rates, puberty in males, reproduction from single litters,
infant mortality up to three weeks of age, etc. These

In Japan, 87% of dairy cows are kept in this way, andresearchers compared the results of differences in theconsidering the fact that cows also have good cognitive

ways pigs were treated, such as, for example, when aability and sensitivity, I think the present Japanese

pig comes close to a person who proceeds to stroke it,system is quite good.

as compared to when a pig comes close to a person
who then kicks it. These experiments compared the

The next experiment I would like to show you waspigsʼ reactions to such treatment. The results showed

performed by Matthews and Ladewig in New Zealand.

higher figures for all measured effects when the pigs

So far we have been talking about cows, but pigs also

were treated with care. Somatic growth was greater,

have high levels of sensitivity and cognitive ability. Pigs

male and female pigs alike matured faster, thecan use their snouts to press buttons. In thisconception rate was higher, litter size was greater andexperiment, which was set up to be like a learning

the mortality rate was lower.

experience, a button was installed on this experimental
box, and it was arranged so that the pigs could obtainIn this way, domestic animals want to have social

food when they pressed the button. Alternatively, theirrelationships, but in reality, 83.1% of pregnant sows are

exercise area could become wider if they pressed the

kept alone in stalls. We need to consider how tobutton, or they could meet their companions if they

improve the present situation.

pressed it. With this kind of “problem setting box”, thetasks are set in such ways as to allow the subjects to beThis is an experiment that we performed. It was aimed

rewarded after pressing the button just once, (or toat establishing how the behavior of domestic animals

ultimately obtain a reward only after pressing thediﬀers depending on whether they are kept enclosed in

button 5 times, 10 times, or 30 times). A pig is placed ina barn or let out to pasture. These are egg-laying hens.

this box, and in the case that the reward is food, even as

This sort of feeding behavior and personal grooming is

the number of required pressing times is increased, thevery often observed in the case of caged hens, but

animals continued to press the button in order to keep

when they are allowed out to pasture, behavior such as

Workshop Ⅲ Welfare and Management of Farmed Animals

15

scanning the environment, walking around, and egg

actually rather difficult to follow in practice. In animal

laying-related behavior increases. The hens begin to live

welfare, it has been recognized that it is very diﬃcult toin quite a diﬀerent way. This means that environmental

persuade people or to get them to learn throughscanning, exercise and egg laying behavior arepractice alone without employing the motivation

programmed into these animals as normal behavior. We

provided by emotion.

compared their behavior when caged against their
behavior when kept free-range in pasture in order toHence, one thing that is referred to extensively in theanalogize what the animalsʼ normal behavior was.

world of animal welfare is cognitive behavioral therapy.
This is based on the idea that cognition comes ﬁrst andWhen the sensitivity, social cognition ability, etc., of

behavior follows on from it. Without the recognition

domestic animals are clariﬁed, it becomes only naturalthat people should pay consideration to animals, there

from the standpoint of ethics that we take reasonable

can be no activity. Then again, in animal protection,

care of their welfare. I am sure that you feel this too. So

emotion is the main consideration. My own feeling isnow, I am going to talk a little bit about animal welfare

that what is required globally is an integration of these

based on such ethical considerations. Speaking of

two concepts.

animal welfare, there is the common injunction to “bekind to animals,” so you may have that kind of image.

On the other hand, as you will understand if you read“Be kind” means to love animals, take care of them andthe Animal Protection and Control Law, its purpose is toprotect them, so the subject of this concept is people.

encourage the spirit and to cultivate the sentiment of

As I will introduce in more detail later, the Japanesecaring for animals. However, the objective of the act is

Animal Protection and Control Law has as its main

not very clearly expressed. That is to some extent a

purpose the cultivation of the emotion of love. This law

weak point.

is intended to nurture peopleʼs love of living things, and
it is centered on the concept of taking proper care ofEverybody, I would like you to please read the text ofanimals throughout their lives. Also, it does not require

the Animal Protection and Control Law. As protected

us to view animals objectively. So there is a possibility

animals, it lists ﬁrst of all domestic animals such as cows,that individuals may develop ways of treating animals

horses, pigs, sheep and goats. This is a revised lawthat are self-righteous. I personally feel this to be a weak

based on previous animal welfare legislation, andpoint of the animal protection concept.

through it we should recognize again that its provisions
should be applied to these domestic animals.

On the other hand, consideration for animals in theWestern world takes the form of “animal welfare”. Under

Animal welfare is a concept that comes from the West“animal welfare”, animals should be allowed to live

and, in my opinion it needs to be integrated with animal

according to how they wish, so the subject of thisprotection worldwide.

concept is the animal, and peopleʼs emotions areirrelevant. We should respect the lives of animals thathave high levels of sensitivity and cognitive ability andas far as possible allow them to live in the way theywish. Under this concept, peopleʼs attitudes toward
animals are objective. The idea is to think about such
subjects as animal pain and suffering, adaptation,
freedom of behavior, etc.
However, as I said earlier, because animal welfare is anobjective concept and does not address emotion, it is16

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産業動物の福祉と経営

Thank you very much.

䇼㪪㫃㫀㪻㪼㩷㩷㪈䇽䇼㪪㫃㫀㪻㪼㩷㩷㪌䇽䇼㪪㫃㫀㪻㪼㩷㩷㪉䇽䇼㪪㫃㫀㪻㪼㩷㩷㪍䇽䇼㪪㫃㫀㪻㪼㩷㩷㪊䇽䇼㪪㫃㫀㪻㪼㩷㩷㪎䇽䇼㪪㫃㫀㪻㪼㩷㩷㪋䇽䇼㪪㫃㫀㪻㪼㩷㩷㪐䇽Workshop Ⅲ Welfare and Management of Farmed Animals

17䇼㪪㫃㫀㪻㪼㩷㩷㪐䇽䇼㪪㫃㫀㪻㪼㩷㩷㪈㪊䇽䇼㪪㫃㫀㪻㪼㩷㩷㪈㪇䇽䇼㪪㫃㫀㪻㪼㩷㩷㪈㪋䇽䇼㪪㫃㫀㪻㪼㩷㩷㪈㪈䇽䇼㪪㫃㫀㪻㪼㩷㩷㪈㪌䇽䇼㪪㫃㫀㪻㪼㩷㩷㪈㪉䇽18

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産業動物の福祉と経営䇼㪪㫃㫀㪻㪼㩷㩷㪈㪍䇽䇼㪪㫃㫀㪻㪼㩷㩷㪉㪇䇽䇼㪪㫃㫀㪻㪼㩷㩷㪈㪎䇽䇼㪪㫃㫀㪻㪼㩷㩷㪉㪈䇽䇼㪪㫃㫀㪻㪼㩷㩷㪈㪏䇽䇼㪪㫃㫀㪻㪼㩷㩷㪉㪉䇽䇼㪪㫃㫀㪻㪼㩷㩷㪈㪐䇽䇼㪪㫃㫀㪻㪼㩷㩷㪉㪊䇽Workshop Ⅲ Welfare and Management of Farmed Animals

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