The layout of this third part of the second volume of Animal Welfare is, in geperal terms, the same as in the earlier issues. There are five refereed papers, a number of Report and comments, seven signed book and video reviews and a letter commenting on an item published in a previous number of the journal.

With this issue the UFAW journal Animal Welfare enters its second year. It is appropriate here to thank two of the Section Editors, Professor Anton Beynen and Dr James Serpell for the work they did on Volume 1 of the journal; they have now stood down as active members of the editorial team but have joined the group of Editorial Advisers. We welcome the two new Section Editors, Professor Jann Hau and Dr Dennis Turner.

This, the fourth issue in Volume 2 of Animal Welfare completes the second year of the UFAW journal. The publication itself can hardly now be described as new: it is being noticed in a wide range of abstracting and indexing journals and is attracting a large number of potential papers.

The contents of this second issue in Volume 2 of the UFAW journal are mainly directed towards three areas of animal welfare concern: commercial poultry production, captive primates and the use of animals in scientific research.

Efforts to promote the psychological well-being of captive non-human primates through the application of environmental enrichment techniques are becoming more common. However, from this perspective relatively little empirical work has been done on the effects of manipulation of the social environment. The data currently available indicate that primates kept in solitary confinement are likely to develop a variety of behavioural and physiological disturbances reflecting reduced well-being, whereas most compatibly socially housed primates appear better adapted. There is always some risk associated with manipulating the social environment for experimental or husbandry reasons, but the risk of deleterious consequences can be reduced by a good knowledge of the animals’ normal repertoire and careful monitoring of how the animals adjust to the new conditions. Attending to the social environment of captive primates is fundamental to their welfare.

The aim of this study was to investigate whether there were differences in fearfulness between laying hens (Gallus gallus domesticus) housed in aviaries and in cages. The tonic immobility (TI) test was used to assess the fearfulness. Norwegian light hybrid White Leghorn hens were housed in battery cages and in three types of aviaries: the Marielund, the Laco-Volétage and the Tiered Wire Floor. Each system housed about 1,500 birds. Tests were performed on 50 birds per housing system at 70 weeks of age in one laying flock and at 30 and 70 weeks of age in the next.

At 30 weeks of age in the second laying flock, the duration of the tonic immobility response was unaffected by type of system. At 70 weeks, however, hens in cages showed tonic immobility of longer duration than hens in aviaries, in the first as well as in the second laying flock No differences in TI between hens from the three types of aviaries were found. The duration of TI did not correlate with plumage condition or body-weight, except for a longer duration of TI with poorer plumage condition in aviaries at 30 weeks. These results indicate that the fearfulness of hens in cages, as measured by the TI test, increased considerably with time. The lower fearfulness shown by hens in aviaries suggests that this important aspect of welfare is more secured in aviaries than in cages.

When individual vertebrates loose grip on their life conditions stress symptoms appear and their welfare becomes problematic. Present day research supports the view that stress can originate when an organism experiences a substantial reduction of predictability and/or controllability (PIC) of relevant events. Behavioural (conflict and disturbed behaviour) and physiological (neuro-endocrine and autonomic processes) aspects of a reduction of PIC are reviewed. The highly dynamic patterns of the homeostatic mechanisms activated during stress make it difficult to deduce any simple relationship between stress and welfare.

A list of relevant stress symptoms has been presented, all of which indicate some stage of serious welfare problems. Their occurrence should never be typical of animals living in a farm, laboratory or zoo housing system. However, if after all this is the case, such systems have to be corrected and replaced by more appropriate ones as soon as possible.

Although the physiological and behavioural changes that can indicate poor welfareare generally agreed upon, using these measures in practice sometimes yieldsresults that are hard to interpret. For example, different types of measure maysuggest quite different things about an animal's welfare. Suchcontradictions are often due to the differing properties of the variables beingmeasured. How each variable responds to a stressor can be affected by severalfactors - the type of unpleasant stimulus to which the animal is exposed; whenand for how long exposure occurs; the animal's psychological state, egdoes it feel that it is in control?; and the time at which the measurement ismade, relative to the stressor. Typical responses also often differ betweenspecies and between individuals, and may even change in a single individual overtime. Furthermore, some responses used to assess welfare lack specificity: theycan be elicited by neutral or even pleasant events as well as by aversive ones.Appreciating these factors is vital when designing experiments, when choosingwhat to measure along with each welfare variable, and when interpreting results.Even after taking these factors into consideration, interpreting a result canstill be difficult. One approach then is to consider the effects on welfare ofthe changes measured, eg if there is immunosuppression, does the animal succumbto disease? Another is to use the animal's behaviour to indicate itspreference for, or aversion to, particular environments. Ultimately, however,interpreting welfare measures involves subjective judgements which will beinfluenced by the nature of our concern for the animal under consideration. Byraising these problems, we hope that this review will highlight and clarify theapparent contradictions that sometimes emerge in scientific studies of animalwelfare, and help researchers improve the designs of their experiments for thebenefit of the animals concerned.

The social behaviour, ranging, and stereotypic behaviours of four red ruffed lemurs (one female, three males) was observed during group formation and release into a 2.25ha natural habitat enclosure at the Duke University Primate Center (DUPC). The female was immediately dominant to all males and there was no female-male affiliation during the initial stages of group formation. The group became identifiable as a unit after release to free-ranging when affiliation and group vocalizations began. Affiliation and vocalizations continued during subsequent recagings. Male dominance rank reflected relative age, but was subject to reversals. The stresses involved in release and group formation, however, can temporarily produce new aberrant behaviours which are soon replaced by normal behaviours. Once released into the large enclosure, stereotypic behaviours became infrequent but did not disappear. Other novel behaviours such as catatonic huddle and all male huddles were observed during release. Natural habitat enclosures can be important tools in the psychological well-being of captive primates.

A questionnaire survey of 385 UK-based university students was used to investigate whether there was an association between pet keeping in childhood and humane attitudes in young adulthood. Subjects gave detailed, retrospective reports of the pets they had kept during their childhoods, and a variety of attitude scales and open-ended questions were used to measure their current attitudes concerning the welfare of both animals and humans. Higher levels of childhood pet keeping were related to more positive attitudes towards pet animals and greater concerns about the welfare of non-pet animals and humans. Ethical food avoidance practices (eg vegetarianism); membership of animal welfare and environmental organizations were also found to be associated with pet keeping during childhood. Knowledge of the experiences that underlie existing variation in humane attitudes will greatly assist the development of more effective humane education programmes in the future.

The responses of 56 cotton-top tamarin monkeys (Saguinus oedipus) to the faecal scent of predators and non-predators were recorded to determine if there was a differential response. Methylene chloride extracts were prepared from the faeces of suspected predators (margay and tayra) and non-predators (capybara and paca) known to co-exist with the tamarins in the wild The faecal extracts were presented to the tamarins on wooden dowels in their enclosures. Untreated dowel and dowel treated with methylene chloride served as controls. The tamarins exhibited high anxiety responses to predator scent compared to non-predator scent which produced low anxiety responses. No sex differences were found but an age difference was apparent: younger individuals were more curious than their elders. The response pattern was observed in captive-born individuals and was not affected by whether or not their parents were wild-caught or captive-born. This indicates that the discrimination of predator and non-predator scents is innate. However, this should not be taken to mean that captive cotton-top tamarins should be re-introduced to the wild without prior predator avoidance training. The implication of this study for animal welfare is that in captive environments where both predator and prey species are kept, it is important that predators, and their faeces, are not situated where prey species can detect their presence through olfaction, because prey species may suffer continual levels of heightened anxiety with possible detrimental effects.

This study measured the amount of time 17 chimpanzee infants devoted to stereotyped body rocking in a variety of nursery settings. Nine females and eight males ranging in age from three weeks to four years were included in the study. Some infants were placed in a peer group at a very early age and were given minimal human contact, while others were provided with more frequent human interaction and were placed in peer groups at varying ages. During the course of the study, infants were housed with varying numbers of chimpanzee companions and some were also provided with a canine companion. Four hundred and thirty-three hours of data were collected. Infants showed a decline in rocking over age and rocked less in the presence of a canine companion. Infant gender, the amount of human contact received at an early age, the age placed with at least one peer companion, and the current number of chimpanzee companions did not affect the time devoted to body rocking. These findings demonstrate that animal managers should look beyond conspecific stimulation for improving the social environment and overall welfare of chimpanzees. These results are further discussed in a framework of identifying possible strategies for minimizing rocking and promoting future behavioural competence in nursery-reared infants.

Although human factors are recognized as influential factors affecting the welfare and productivity of farm animals, only limited research has been conducted to identify these important human characteristics and to quantify their effects. During the last 13 years we have studied two apparently important human factors: the attitude and the behaviour of stockpersons towards farm animals.

We have proposed that in intensive animal production systems there are some important sequential relationships between the attitude and behaviour of the stockperson towards farm animals and the behaviour, performance and welfare of farm animals. Basically we have suggested that because a stockperson's behaviour towards animals is largely under volitional control it is strongly influenced by the attitudes and beliefs that the stockperson holds about the animals. Furthermore, the stockperson's behaviour towards animals affects the animals’ fear of humans which, in turn, affects the animals’ productivity and welfare. It is the occurrence of a stress response by animals which are highly fearful of humans which places their productivity and welfare at risk We have published data which strongly support these interrelationships between human attitude and behaviour and animal behaviour, productivity and welfare. This paper reviews this and other research on this subject. The results of research in the pig industry and to a lesser extent, the poultry industries indicate the excellent opportunity which exists to improve animal productivity and welfare by training and selecting stockpersons to have desirable attitudinal and behavioural profiles towards farm animals.

From two weeks of age female broiler breeder chickens were fed either on a commercial daily ration (R), twice that amount (2R), or ad libitum (AL). Motivation to eat in R and 2R birds was compared every third week with that of AL birds subjected to 3-72h food deprivation. AL and 2R birds grew three and two times faster than R birds to 20 weeks, and AL birds ate two to four times as much per day as R birds, depending on age and on whether birds of the same age or weight were compared. When feeding motivation was measured in 16min tests with an operant procedure, numbers of responses by R and 2R birds were not related in a consistent way to the time since their daily meal ended Responses by AL birds were correlated consistently with the preceding period of food deprivation, but it was not possible to express hunger in R and 2R birds in terms of equivalent deprivation in AL birds, as intended, because feeding motivation in the two situations differed in magnitude. Instead, it was calculated that motivation to eat in R and 2R birds, from 8 to 20 weeks, was 3.6 and 1.9 times greater than that of maximally (72h) deprived AL birds. Another measure of feeding motivation with different birds, rate of eating in 10min tests, produced a similar index of hunger with 2R but not R birds. It is concluded that broiler breeders fed on the commercial ration eat only a quarter to a half as much as they would with free access to food, and that they are highly motivated to eat at all times. The modern broiler breeder industry is caught in a welfare dilemma, since on the one hand stock appear to be chronically hungry, while on the other hand less severe food restriction leads to reduced fertility and health problems.

Straw bedding provides a number of functions which affect the behaviour and welfare of pigs including comfort, recreation and diet. It has been suggested that the importance of these different functions will vary depending on the life/production stage of the pig. The available literature indicates that all of the above functions are relevant to all the different stages except newly born piglets. The occupational value of straw appears to be highly important. The actual mechanisms by which straw affects the pig's motivation systems are still poorly understood. It is therefore uncertain whether suitable alternatives to bedding exist or even if straw bedding in itself is completely satisfactory. Until satisfactory alternatives are available straw bedding should continue to be recommended in terms of pig behaviour and welfare.

Social role has been defined as a pattern of behaviour characteristic of a class of individuals within a group. The concept was developed by primatologists both to describe individual variation in behaviour in social groups and to be used in addition to hierarchy as a model for primate social organization. Cattle have been shown to express considerable individual variation in behaviour. Furthermore, cattle and primates show some similarities with respect to their social behaviour. This may indicate that the concept of social roles might be useful to those studying cattle behaviour. After a brief literature review it is concluded that the concept may indeed be applicable to cattle. The possible welfare implications of this are first, that it would offer a new approach for the study of individual differences in behaviour - important to the understanding of how animals cope with their environment in captivity. Second, it could help the understanding of social behaviour in domestic species. It is suggested that an interchange of ideas between primatologists and applied ethologists is needed.

Full ‘rehabilitation’ of sick and injured wild animals should include restoration to the wild. Few attempts have been made to discover the fate of released ‘rehabilitated’ animals, a significant omission in terms of animal welfare. They may die, unable to find adequate food or nest sites in unfamiliar places. They may be ostracized or even attacked by wild resident conspecifics.

Eight ‘rehabilitated’ hedgehogs (Erinaceus europaeus) were released into farmland and radio-tracked to monitor their movements and nesting; they were also weighed frequently. Three wild hedgehogs caught on site were studied in parallel.

Only one animal remained close to the release site throughout the eight week study. The rest scattered, perhaps seeking more familiar terrain. One animal died, possibly not having fully recovered from its original disorder. Of the seven others, three survived at least seven weeks, but two then met with accidental deaths (drowning and road kill). Contact was lost with four animals, but circumstances suggested that they were probably still alive at least five weeks after release. There was no evidence of negative interaction with local wild hedgehogs nor any indication of difficulty with foraging, nesting or finding their nests again. Body-weights were generally maintained or increased. It is concluded that rehabilitated adult hedgehogs can probably cope well with release.

Captive chimpanzees fed at regular, predictable intervals are known to exhibit higher rates of aggression immediately prior to, and during feeding. Presumably, anticipation of food creates tensions leading to increased agonistic interactions prior to feeding. This study was conducted to determine if seasonal variabilities might contribute to pre-feeding agonism. A quantitative examination was made looking at events affected by seasonal (summer versus autumn) changes. Seasonal fruit diversity and the amount of available space during feeding bouts in socially housed, captive chimpanzees were tested for an effect on pre-feeding agonism. Groups were observed for a five-week period during both seasons. Each social group was observed five times per season for 30 minutes, beginning 30 minutes prior to the morning feeding. All occurrences of agonistic behaviours were recorded. Average frequencies of agonistic behaviours were calculated for each group and compared across season using a Wilcoxon matched-pairs test to determine the effect of seasonal fluctuations in fruit diversity. There were no significant differences in the number of agonistic behaviours exhibited during summer versus autumn seasons. A strong negative correlation was found for agonistic behaviours in both seasons: as space decreased, agonism increased in both summer and autumn. In addition, males scored significantly higher in the summer versus the autumn for submissive behaviours when space decreased. The provision of a variety of seasonal fruits did not result in increased pre-feeding agonism in captive chimpanzees. In fact, cage size had a greater effect on levels of agonism than did the provision of seasonal fruits.

A simple technique for investigating gut passage times in small New World primates was developed, which produced good results without any need for special housing or diet, or for the separation of monkeys from their groups. This technique, which allowed the administration of a faecal marker, chromium oxide, to specific individuals, was used to investigate gut passage times in five species of the genera Callithrix, Saguinus, Leontopithecus and Callimico. Overall, average gut passage time was 4.5 hours, and there were no species differences. Such nondisruptive methods could help in assessing the effects of dietary changes in captive monkeys, and therefore be of considerable value in improving captive diets and hence welfare and breeding success.

Individual differences in behaviour may be examined at two levels. First, individuals may differ in terms of frequencies, durations and/or patterning of particular measures of their behaviour. Second, individuals may differ in their temperament, ie in the way they react to environmental change and challenge. Individual differences in temperament are particularly relevant to animal welfare studies, for the welfare of an individual largely depends on whether it can cope with environmental challenge. Whereas the study of individual differences in behaviour at the first level may be achieved by using standard behavioural methods, the study of individual differences in temperament requires the use of more unusual methods, namely observers’ ratings and behavioural tests. Observers’ ratings provide information on subtle aspects of an individual's behaviour that could otherwise be overlooked. Behavioural tests facilitate comparisons between individuals in a more standardized way. It is suggested that both systems should be used together.

Taking individual differences into account when designing experiments may help reduce variability in studies on welfare issues and understanding the causes of individual differences in temperament may allow us to reduce the incidence of some welfare problems.