D. M. Broom

The scientific assessment of animal welfare

Abstract The welfare of an individual is its state as regards its attempts to cope with its environment. Welfare varies on a continuum from very good to very poor, and it can be assessed precisely. Information about what conditions might result in good welfare can be obtained from studies of preferences, buth the importance of the preference to the individual must be assessed. Measures which show how poor welfare is when animals encounter short-term or long-term problems may be physiological, behavioural, or concerned with individual production or disease. Individuals vary in the coping methods which they use, so any one measure may indicate poor welfare and absence of evidence using one measure does not mean that there is no welfare problem.

Physiological and reproductive correlates of behavioural strategies in female domestic pigs

Abstract Thirty-seven pregnant primiparous domestic pigs, Sus scrofa , were introduced into a large indoor pen. The pigs were divided into three groups according to their ability to displace others in agonistic interactions and the behavioural characteristics of these groups were investigated. High Success pigs were able to displace at least as many individuals as displaced them. They were characterized by low levels of inactivity, high involvement in social interactions and high aggression. No Success pigs never displaced any other pig and were most inactive, least aggressive and showed low involvement in social interactions. Low Success pigs were able to displace some pigs but were more often displaced themselves. They were aggressive, despite their relative lack of success, and experienced the highest levels of aggression from and displacement by others. During the first month in the group, High Success pigs gained the most weight. Low Success pigs had the highest basal levels of salivary cortisol and showed the highest peak cortisol levels in response to an adrenocorticotrophic hormone challenge test. At the first parturition, Low Success pigs produced the lowest weight of piglets born alive. Hence there were more adverse effects associated with being aggressive and often displaced than with being aggressive and usually winning, or being unaggressive and involved in few interactions. The strategy used to cope with the social environment may be as important as the success achieved in agonistic interactions, at least in terms of consequences for physiology and reproduction.

Effects of the eyefluke, Diplostomum spathaceum, on the behaviour of dace (Leuciscus leuciscus)

The behaviour of dace infected with Diplostomum spathaceum was investigated in the laboratory. As the number of parasites present in the eye increased, the efficiency with which the fish fed on Gammarus pulex declined. The loss of efficiency was compensated for by an increase in the time devoted to feeding. Heavily infected fish spent more time in the surface layers of the water. This may increase the likelihood that a gull might eat the fish and thereby continue the life-cycle of the parasite. The parasite modifies the behaviour of its host in a way that increases the parasites chances of survival at the expense of the host.

Timing and causes of piglet mortality in alternative and conventional farrowing systems

The causes and timing of piglet mortality were studied in different farrowing systems. In the first experiment 198 litters were recorded in three systems, two of which allowed the sows to move freely, and the third restricted them in conventional crates. More piglets were weaned from the conventional crates than from the open systems and they grew more quickly. More than half the liveborn mortality occurred during the first four days after parturition. In the open systems, 17 per cent and 14 per cent of the piglets born alive were crushed, compared with only 8 per cent in the crates. In the second experiment, 29 sows and litters were studied in detail in a communal pen system during the first seven days of lactation. Three-quarters of the liveborn mortality was due to crushing. The total number of piglets dying per litter, including stillbirths, was significantly associated with the total litter size and the sows parity. The percentage livebom mortality was significantly associated with the parity and body length of the sows and with the within-litter variation in the birth weight of the piglets. Individual birth weight was closely associated with percentage survival. Only 28 per cent of piglets weighing less than 1.1 kg at birth survived to seven days.

The influence of litter size and parental behaviour on the development of Mongolian gerbil pups.

Abstract Undisturbed pairs of Mongolian gerbils were observed rearing litters of one, three or five pups. Pup behaviour and physical development were also monitored. Activities of both parents are influenced by litter size; some activities, e.g. sniff pups, being performed the most with large litters but others, e.g. nest-build, being performed the most with small litters. Pups from litters of three show the fastest behavioural and physical development. The presence of the male influences female activities and offspring development. Females nest-build less and sniff the pups less when the male is present. Pups reared with their father, however, open their eyes earlier and are behaviourally more advanced than are pups reared by the mother alone.

A comparison of the welfare of sows in different housing conditions.

Twelve sows in good quality unstrawed stalls, three groups of five sows in strawed pens with individual feeding stalls and sows in a 38-sow group in a strawed yard with an electronic sow feeder were compared during the first four parities. They originated from the same source, were about 9 months of age and in the 7th week of their first pregnancy at the start of the experiment and were kept in adjacent rooms in a building, cared for by the same staff and given the same diets at a rate of 2·2 kg/day per animal. No new animals were added to the groups or stalls during the study and animals returned to the same condition after periods in farrowing and service accommodation. Using a wide range of welfare indicators, it was clear that stall-housed sows had more problems than group-housed sows and that tliese problems were worse in the fourth than in the first pregnancy. By the fourth pregnancy, stall-housed sows spent proportionately 0·14 of time showing activities which were clearly stereotypies and much time on activities which were sometimes stereotyped, i.e. ‘drinking’ and rooting or chewing at pen fittings making a total of proportionately 0·50 of time. Comparable figures for group-housed sows were much lower (0·037 and 0·081 in total). Stall-housed sows were also more aggressive than group-housed by the fourth pregnancy and their body weights were lower. There were no differences using physiological or immunological tests or measures of reproductive output. When the two group-housing systems were compared, sows in the electronic feeder system showed more fighting, especially soon after initial mixing, but fewer total agonistic interactions than sows in groups of five during the first pregnancy. Oral stereotypies were slightly higher in small groups, perhaps because of smaller pen space, than in larger groups but much lower than in stalls. By the fourth pregnancy there were few differences between sows in small and large groups and all seemed to have adapted well to the conditions. Evaluation of welfare in different housing systems requires use of a wide range of measures and of long-term studies.

Welfare, Stress, and the Evolution of Feelings

Publisher Summary This chapter discusses the different kinds of feelings and considers the origin and possible function of each feeling. Each of these feelings has a biological role that complements various other anatomical, physiological, and behavioral mechanisms. All have some potential for improving fitness and most are likely to have been the subject of considerable selection pressure, but some aspects of feelings are likely to be just epiphenomena of neural mechanisms. With this view that most aspects of feelings have evolved like other biological mechanisms and that they help significantly in coping and responding, a single view of welfare as the state of an individual as regards its attempts to cope with its environment becomes clearer. Feelings are an important part of the welfare of an individual and should be assessed as well as possible. Other coping procedures and effects of the environment on the individual should also be assessed. An effect on an individual that is adverse in the long term is categorized as stress. Programs for trying to evaluate and improve welfare should combine the use of experiments to assess what is important to the individual by measuring the strengths of preferences, with monitoring studies in which feelings and other aspects of welfare are assessed more directly.

Hormonal and physiological effects of a15 hour road journey in sheep: Comparison with the responses to loading, handling and penning in the absence of transport

A controlled study was carried out to investigate the physiological effects of road transport on sheep. Animals (n = 10; body weight 38.9 +/- 1.3 kg), previously with catheters in their jugular veins, were rounded up and loaded onto a vehicle where they were held in a communal pen with eight other lambs. Blood samples were taken at 30 min intervals during the next 15 h while the vehicle remained stationary or was driven a distance of 548 miles (876 km). Measurements were made of plasma concentrations of cortisol, prolactin, creatine phosphokinase and lactase dehydrogenase isozymes and also of plasma osmolality, haematocrit and body weight; heart rate was also recorded in one animal. Loading and the start of driving produced large increases in cortisol and prolactin concentrations. Heart rate also increased whereas osmolality and haematocrit decreased. The major changes in hormone release occurred in the first 3 h period while, during the remaining 12 h, the stimulatory effect of transport was present but small. Body weight loss was similar under both stationary and driven conditions.

Behavioural and hormonal responses of pigs during transport: effect of mixing and duration of journey

Two experiments investigated the welfare of pigs during transport. In experiment 1, 12 groups offour 90-kg pigs were transported to slaughter in a commercial livestock lorry for 1·5 h. Half the animals were transported in their social groups (unmixed condition) and half were transported with groups of previously unfamiliar pigs mixed together (mixed condition). Behaviour was recorded, a general activity index scored and saliva samples taken at different stages of the journey for analysis ofcortisol. Pigs spent most of their time standing in both conditions. The journey was very rough (as revealed by characterization with an accelerometer) and in the unmixed condition the pigs appeared to stand to reduce travel sickness. In contrast, in the mixed condition, this preference for standing seemed to be due to fighting which stressed and exhausted the animals (the general activity index was three times the unmixed condition). Levels of salivary cortisol were higher in the mixed condition at the beginning, middle and end of the journey. In experiment 2, six 35-kg pigs, prepared in advance with jugular vein catheters, were loaded onto a commercial livestock lorry (09.30 h) where they were individually penned. The vehicle remained stationary with the engine off and blood samples were taken at 30-min intervals during the next 8 h (control). Two days later this procedure was repeated while the vehicle was driven for 8 h (on main roads and motorways). Plasma concentrations of cortisol and beta-endorphin increased markedly in both conditions immediately after loading. Cortisol levels were greater (relative to control) at the beginning, in the middle and at the end of the journey. Concentrations of beta-endorphin did not differ between control and experimental conditions except during the final 180 min of the journey when the control levels were higher.

Behavioural interactions of dairy cows with their newborn calves and the effects of parity

Abstract Continuous observations of 82 individually penned Friesian cows and their calves were made during the first 6 h post partum. The behaviour observed was similar to that described for wild ungulates of the ‘hider’ type. Cows showed a marked decrease in calf-directed activities with time after parturition. This was more pronounced in older animals, which recommenced ingestive behaviour sooner. The incidence of licking and other maternal behaviour depends upon the characteristics of the calf and upon the state of the mother. Close proximity between cow and calf was maintained, in small calving pens, by the mother at the first three calvings but by the calf after these. The eating of the afterbirth is considered to be anti-predator behaviour. Calves of primiparous dams spent more time suckling and suckled from more quarters than did calves of older cows. Primiparous dams showed a higher incidence of abnormal maternal behaviour.