The vocalisations of animals are results of particular emotional states. For example, the stress screams of pigs may be indicators of disturbed welfare. Our objective was to develop a system to monitor and record levels of stress calls in pigs, which could be employed in environments of breeding, transportation and slaughter. Using a combination of sound analysis by linear prediction coding and artificial neural networks, it was possible to detect the stress vocalisations of pigs in noisy pig units with few recognition errors (<5%). The system (STREMODO: stress monitor and documentation unit) running on PCs is insensitive to environmental noise, human speech and pig vocalisations other than screams. As a stand-alone device it can be routinely used for the objective, non-invasive measurement of acute stress in various farming environments. The system delivers reliable, reproducible registrations of stress vocalisations. Its detection quality in commercial systems was found to correlate well with that of human experts. STREMODO is particularly well-suited for comparisons of housing and management regimes. Since the system can be trained to recognise various animal vocalisations, its use with other species is also well within its scope.

Visitors to zoos can be a potential source of stress to captive-housed primates, resulting in increased abnormal behaviour and intra-group aggression. Finding a way to screen primates from human visitors may be one method of decreasing stress and enhancing animal welfare. For this study, the behaviour of six zoo-housed gorillas was studied for one month during standard housing conditions (control condition) and for a further month following the installation of a camouflage net barrier to the viewing area of the exhibit (barrier condition). Visitors’ (n = 200) perceptions of the animals and the exhibit were also recorded during each condition. The net barrier had a significant effect on some components of the gorillas’ behaviour. The gorillas exhibited significantly lower levels of conspecific-directed aggression and stereotypic behaviours during the barrier than the control condition. The net barrier also had a slight effect on visitors’ perceptions both of the animals and of their exhibit. The gorillas were considered to look more exciting and less aggressive during the barrier than the control condition. The exhibit was also considered to be more appropriate for visitors following the introduction of the camouflage netting. Overall, the addition of a screen such as camouflage netting could be considered a positive change, resulting in a reduction in those behaviours typically induced by large groups of visitors and an improvement in public perceptions of the animals and their environment.

Commercially reared ostrich chicks are typically kept in barren, indoor environments. This experiment investigated the effects of environmental enrichment on the pecking behaviour, exploration, food consumption and novelty responses of ostrich chicks aged 10 to 21 days. Four groups of 20 randomly selected ostrich chicks were housed in heated huts at one day of age (Day 1), and at Day 10 were allowed access to sand-covered areas (30 m2) that were either barren (control: n = 2 groups) or enriched with cabbage, coniferous cones and sticks (enriched: n = 2 groups). Pecking behaviour was recorded by focal sampling the behaviour of five chicks per group for four 5 min periods per day on Day 10 and Day 13. All enriched chicks pecked at the cabbage, of which they consumed considerable amounts (26 ± 3 g/chick/day). The enriched chicks did not have higher overall pecking frequencies but tended to peck less at fixtures in the pen, compared to control chicks. Additionally, the enriched chicks showed increased exploration in terms of the percentage of chicks observed outside the heated huts. In a novel object test, enriched chicks stayed closer to and delivered more pecks at sorrel (Rumex acetosa) than did control chicks, whereas there was no difference between the treatment groups in their response to adult ostrich feathers. Enriched chicks consumed more food (79 ± 0.4 g/chick/day) than did control chicks (67 ± 09 g/chick/day) during the experimental period. We suggest that environmental enrichment improves the welfare of ostrich chicks in terms of increasing exploration and reducing pecking at fixtures in the pen, without compromising food consumption.

Elements of husbandry procedures, such as handling, may disrupt rodent social behaviour. Such effects may be contingent upon the familiarity between individuals and upon the quality and quantity of the disruption. We investigated this issue using laboratory rats. We placed 36 rats into groups of three. At the point of group formation, and at 24 h, 7 days and two weeks afterwards, individuals received one of three treatments: ‘handling’, exposure to novel conspecific ‘urine’, or ‘control’ (undisturbed), for a duration of either 5 or 15 mins. We used a social recognition test to measure the ability of the rats to recognise the urine of group members of increasing familiarity following the implementation of these treatments. The ‘control’ treatment did not appear to disrupt social recognition. The 5 min ‘urine’ treatment appeared to disrupt recognition only when the rats had received the briefest experience of the ‘familiar’ urine (5 mins). The 5 min ‘handling’ treatment, however, appeared far more disruptive, with an apparent disruption of social recognition even when familiarity with the urine donor was high (eg 7 days of group housing). Both the ‘handling’ and ‘urine’ treatments appeared more disruptive when presented for an increased duration (15 mins). There was also some evidence that increased experience of the handling procedure might reduce its disruptive effect. The results of this study have several implications for the welfare of laboratory-housed rats, and these are discussed.

Charolais × and Suffolk × Mule lambs of less than one week of age were castrated and tail docked using a standard rubber ring technique. After these procedures, their behaviour was monitored for I h. Their respiration rates and scrotal sac measurements were also recorded. Both breeds of lamb exhibited abnormal behaviour patterns following these procedures. The recumbent behaviour pattern of both breeds was remarkably similar but their standing behaviour differed markedly. The Charolais × lambs were significantly more active and had significantly higher respiration rates compared with the Suffolk × lambs. They also took a greater amount of time to recover to a normal posture. Their abnormal behavioural responses suggested that both breeds of lamb experienced acute pain following castration and tail docking, but the type of behaviour exhibited was breed-dependent. The findings suggest that different breeds of lamb may experience different levels of distress in response to the same husbandry procedure. Alternatively, they may simply reflect a difference in the character and temperament of the breeds studied.

As part of a translocation project, 28 Eurasian otters (Lutra lutra) were captured from the wild and transported to the Barcelona Zoo for veterinary evaluation, quarantine and intraperitoneal implantation of telemetry devices. Eleven animals were injected with the long-acting neuroleptic (LAN) perphenazine enanthate at the time of capture and the remaining animals served as a control group. During their time in captivity, which averaged 23 days, all of the animals were bled three times. Haematological and biochemical parameters were evaluated, including red blood cell count (RBC), haemoglobin (Hb), white blood cell count (WBC), blood urea, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (AP), lactate dehydrogenase (LDH), creatine kinase (CK), albumin, and serum cortisol. No significant differences were found between treated and control otters except for monocyte count, which was higher in treated animals. Time after capture had an effect on many parameters. RBC and Hb decreased at first and then increased, while WBC and segmented neutrophils decreased over time. Most of the biochemical parameters considered to vary in relation to stress, including AST, ALT, CK, AP and LDH, decreased over time, suggesting that the stress responses of the animals decreased throughout the period of captivity. However, no significant change in serum cortisol levels was noted. The lack of effect of perphenazine treatment on haematological parameters should encourage further research on other stress indicators applicable to wild animals, such as behaviour or faecal cortisol concentration. Finally, the results obtained in this study suggest that, when captive conditions are adequate, keeping wild-caught animals in human care for a period of time prior to their release into the wild can be beneficial. However, further studies taking into account other welfare indicators would be useful.

Provision of adequate space for captive animals is essential for good welfare. It affects not only their behaviour but also determines whether there is sufficient room for appropriate environmental enrichment. Most importantly, appropriate cage size permits captive animals to be housed in socially harmonious groups and to fulfil their reproductive potential. For animals used in the laboratory, the environment can be an additional source of suffering and distress. If they can be better housed and cared for to reduce the overall impact of experiments upon them, then we are obliged to do so for ethical, legal and scientific reasons. Practically all current guidelines specify minimum cage sizes for laboratory primates based on unit body weight. We believe that no single factor is sufficient to determine minimum cage sizes for primates, and that instead a suite of characteristics should be used, including morphometric, ecological, social and behavioural characteristics. Here we explore the relevant differences between tamarins (Saguinus labiatus and S. oedipus) and marmosets (Callithrix jacchus) that have a bearing on setting minimum cage sizes. These include: body size; arboreality and cage use; home range size, mean daily path length and stereotypic behaviour; breeding success in the laboratory; and species predisposition and aggression. We conclude that it is even more important to provide tamarins with a good quantity of space in the laboratory than it is marmosets if well-being and breeding success are to be maximised.

The effectiveness of head-only electrical stunning of broilers, with a root mean square (RMS) current of 100 or 150mA delivered using either 50, 400 or 1500Hz sine wave alternating current (AC), was investigated. The changes occurring in the spontaneous electroencephalogram (EEG) were evaluated using Fast Fourier Transformations (FFT) to determine the impact of the amount and frequency of stunning current on total (2-30 Hz) and relative (13-30 Hz) power contents in the EEG. Induction of epileptiform activity and reduction in the EEG power contents to less than 10% of pre-stun levels from the end of epileptiform activity were used as indicators of effective stunning. The duration of unconsciousness and insensibility was determined on the basis of the return of EEG power contents. In addition, the changes occurring in somatosensory evoked potentials (SEPs) were subjectively evaluated to determine the impact of stunning treatments. The results of ANOVA (repeated measures) showed statistically significant effects of interactions between the current frequencies, amount of current and repeated measures on changes in EEG power contents (P < 0.001). Stunning broilers with 150 mA delivered using 50 Hz resulted in EEG changes that were indicative of more pronounced neuronal inhibition following epileptiform activity and also lasted longer than was the case when broilers were stunned with 150 mA delivered using 400 Hz. Stunning broilers with 100 mA delivered using 50 Hz resulted in changes very similar to those observed after stunning with 150 mA of 50 Hz, but which lasted for a relatively shorter time. However, these changes were more pronounced and lasted longer than did stunning with 100 mA delivered using 400 Hz. The effects of stunning broilers with 150 mA of 400 Hz were similar to those found after stunning with 100 mA of 50 Hz. By contrast, stunning broilers with 100 mA of 1500 Hz failed to fulfil the criteria set out in this study. Stunning of broilers with 150 mA of 1500 Hz induced epileptiform activity but failed to reduce EEG power contents to less than 10% of pre-stun levels. Therefore, the stunning of broilers with 100 or 150 mA of 1500 Hz may not be adequate to avoid pain and suffering during slaughter. Thus, minimum currents of 100, 150 and 200 mA should be delivered whilst using 50, 400 and 1500 Hz, respectively, to achieve effective electrical stunning in broilers. Severing of the carotid arteries in the neck following head-only electrical stunning, and high frequency (> 125 Hz) electrical water bath stunning of broilers should also become a statutory requirement to prevent the return of consciousness during bleeding.

Maternal behaviour in free-ranging sows is normally performed in an isolated nest that the sow has built during the pre-parturient period. Consequently there is much concern over the use of restrictive farrowing crates, in which manipulable substrates are often not provided, for parturient sows under commercial conditions. This study examined the impact of the provision of space and substrate on the performance of maternal behaviour by gilts (primiparous sows) on physiological indicators of stress and on the progress of parturition. Gilts had an indwelling jugular catheter implanted 12 days before their expected farrowing date. At 5 days before expected farrowing, 34 gilts were placed in one of four farrowing treatments: crate without straw (C, n = 8), crate with straw (CS, n = 9), pen without straw (P, n = 9) or pen with straw (PS, n = 8). Behavioural observations of gilts and piglets were made during an 8 h period after the expulsion of the first piglet. Blood samples were taken via a catheter extension to minimise disturbance throughout the parturition period. Gilts in all treatments were most active in the first 2 h: performing more standing/walking, substrate-directed and piglet-directed behaviour. This active phase was followed by inactivity and passivity, as has been seen in free-ranging sows. However, this temporal profile of behaviour was more pronounced in the penned gilts (P and PS), which were more active during the first 2 h than the crated gilts (C and CS). Gilts in crates spent longer sitting throughout the 8 h period and tended to show more savaging of their piglets. Savaging gilts were found to be more active and responsive to piglets. The provision of straw did not alter gilt behaviour but did alter piglet behaviour, with piglets that were born into environments with no straw (C and P) spending more time next to the gilt's udder. The provision of straw increased the length of parturition (CS and PS), but this did not have detrimental effects on piglet survival. Plasma cortisol was unaffected by space or substrate, however, plasma ACTH was found to be highest in C gilts during the second hour of parturition. Plasma oxytocin was unaffected by space or substrate, however, there was a positive relationship between plasma oxytocin and unresponsiveness to piglets. In conclusion, it appears that farrowing crates thwart interactions between the gilt and her piglets, and that the provision of space during parturition, irrespective of straw availability, facilitates the performance of maternal behaviour that more closely resembles that performed by free-ranging sows.

The reversibility and flexibility of contraceptive methods generally allow for improved genetic and demographic management of captive populations. Earlier studies have produced conflicting results regarding the restoration of reproduction after using melengestrol acetate (MGA) implants in golden-headed (Leontopithecus chrysomelas, GHLT) and golden lion tamarins (L. rosalia, GLT): two closely related species that are physiologically and genetically very similar. The present study investigates the nature of this inter-species difference, presents new data on GHLTs and compares this with published data on GLTs. Analyses showed that around 34% of the GHLTs resumed breeding after their MGA implants were removed or had expired. Non-implanted GHLTs (control group) were significantly more likely to reproduce than females previously treated with an MGA implant, regardless of whether the implant was removed or left to expire. Younger and parous female GHLTs in the control group were more likely to start reproducing. In implanted females, only parity had an impact, with parous females being more likely to resume breeding than non-parous females. In contrast, data published on GLTs indicate that 75% of GLT females resume breeding, and that removing the implant increases the probability of reproduction occurring. Available data suggest that the observed inter-specific differences are related to differences in the weights of the implants used for the two species. For GHLTs, adjusting MGA doses and/or the sizes of the implants currently administered may be required in order to preserve the reproductive potential of individuals. Apart from potentially negative medical and welfare consequences for individual GHLTs, the reduced reversibility of MGA implants also impacts on management practices used to achieve the objectives of conservation breeding programmes. Finally, this study stresses the importance of evaluating the suitability of contraceptive methods at a species-specific level.

Enhancing the complexity of the environments of captive animals is often referred to as environmental enrichment, and aims to have positive effects on the animals’ well-being. Such enrichments may have consequences both for so-called ‘normal’ behaviour and for the pathophysiology of the animals in question. The effects of a lack of environmental complexity, including social isolation, on home cage behaviour and on pathophysiology in rats is considered in this review. Several preference tests on rats — choice tests and operant tests — indicate a preference for bedding, nesting material and social contact. Contradictory research results concerning the need for gnawing objects per se are more difficult to interpret, and it is argued that excessive gnawing may be indicative of primary frustration and hence reduced welfare. One disadvantage of providing environmental enrichment to laboratory animals is a possible increase in subject variability, resulting in the need to use a greater number of test animals. However, this increased variability seems to be inconsistent and is not very well documented. It is argued that in cases where the behavioural benefits of environmental enrichment justify the use of more animals, better welfare should be more highly valued than a reduction in the number of animals used.

A questionnaire-based survey of attitudes to the introduction of the Ethical Review Process (ERP) was carried out in late 1999, some 6-9 months after the introduction of the ERP to all establishments involved in animal experimentation in the UK. Five categories of people working under the Act were surveyed (Certificate Holders, Named Veterinary Surgeons, Project and Personal Licensees and Named Animal Care and Welfare Officers) and about 45% of the 1636 questionnaires were returned. In general, respondents believed that licensees received training in their responsibilities under the Act and that all groups received training in animal welfare and ethics. A high proportion of respondents believed that the quality of training in animal welfare was good or excellent, but about a quarter thought it only adequate. Training in ethics was believed to be of lower quality. A high proportion of Named Veterinary Surgeons and Project Licensees, but fewer Personal Licensees, reported that they attended seminars, talks and training courses about animal welfare and ethics. The majority of respondents believed that the ERP had had no effect on training and animal welfare, although a minority thought it had led to improvements. About two thirds of licensees and Named Veterinary Surgeons reported that their work with animals was monitored, although a third or more believed that their competence was not assessed. The adequacy of training and the assessment of competence are essential for maintaining high standards of animal welfare. Certificate Holders believed that training and monitoring was more effective, and Personal Licensees believed it less effective, than did other groups.

The illuminance and spectral power distribution in 19 duckling and 16 turkey poult houses in the UK were sampled. Illuminance was highly variable within duckling houses and to a lesser extent in housing for turkey poults. In a free choice experiment, the preferences of commercial ducklings and turkey poults for four incandescent illuminances (<I, 6, 20 and 200 Ix; Osram, 60 W, Pearl) were tested at 2 and 6 weeks of age. Four replicate flocks of 12 birds were given continuous access to four compartments illuminated with each illuminance for six days. The illuminances were changed daily between the compartments. After two days of conditioning, the birds’ location and behaviour was recorded at 10 min intervals over 22 h. Nine and 12 defined behavioural categories were recorded for the ducklings and poults respectively. Ducklings spent significantly more time occupying the three brightest light environments both at 2 and 6 weeks of age, and the least time in the dimmest. Illuminance had a significant effect on the partition of behaviours amongst the light environments. At 2 weeks of age, locomotion and environmentally directed pecking occurred most often in 6, 20 and 200 lx, whereas at 6 weeks, preening and feeding also occurred more often in these light environments. At 6 weeks of age, resting, standing and drinking occurred significantly more often in 6 lx than in the dimmest environment. Turkeys spent most time in the brightest environment at 2 weeks of age, but in 20 and 200 Ix at 6 weeks. This change in overall preference was reflected in the partition of different behaviours between the light environments. At 2 weeks of age, all behaviours were observed to occur most often in 200 lx. At 6 weeks, resting and perching were observed least often in <I lx, whereas all other activities were observed more in the two brightest light environments. These results show that ducklings and turkey poults have significant but differing preferences for illuminance, and imply that some spatial or temporal variation in the ambient illuminance of housing would be consistent with their preferences.

Animals within zoo environments are learning continuously: they learn signals that predict when food is going to arrive or that the presence of a certain person means that something unpleasant may happen. They may learn to control their environment and caregivers: for example, they may learn that if they perform a particular behaviour (eg repetitive behaviour) they will receive a reward (ie food or attention from a caregiver). Using standard operant conditioning and classical conditioning techniques we can easily modify the behaviour of animals in zoos. Animals can be trained to comply with almost all minor veterinary procedures and examinations, such as injection, the measurement of heart rate, the cleaning of teeth and the treatment of superficial injuries. Compliance can be achieved using standard animal learning abilities without the need for punishment type I (ie physical punishment) or immobilisation (chemical or physical). In this paper we discuss how we apply learning theory to such procedures, the dangers associated with such programs (eg injury to the trainer) and the benefits (eg the treatment of large endangered animal species without the use of anaesthetic drugs). Additionally, we briefly discuss the selection and management of animal trainers. The methods we describe here are equally applicable to laboratory, farm and pet animals. Finally, as with all management processes applied to animals, a written policy on animal training needs to be produced by any institution training animals.

The nose-ringing of outdoor pigs (Sus scrofa), although commonly practiced as a means to inhibit rooting behaviour and therefore reduce pasture damage and soil erosion, has been questioned on ethical grounds and alternatives are being sought. In this experiment, the effect of overground environmental enrichment was assessed as a possible alternative. 12 multiparous sows were housed in groups of four and randomly allocated to one of three treatments in a 3 × 3 Latin square design. Treatments were: 1) no environmental enrichment, 2) edible overground enrichment in the form of grass silage, and 3) inedible overground enrichment in the form of branches and tyres. Sows that received silage as overground enrichment spent significantly less time rooting the paddock (P < 0.01) than did sows on the other two treatments. The absence of a significant difference between treatments in overall foraging time budgets suggests that the manipulation of edible substrates may substitute for rooting behaviour in outdoor sows.

Human interaction as environmental enrichment for chimpanzees (Pan troglodytes) and other primates is widely promoted and believed to be of value, but has been subject to little objective evaluation. This study assessed the effects of positive human interaction (eg relaxed treat feeding, playing, and other forms of social interaction compatible with personnel safety) on the behaviour of adult chimpanzees. Subjects were housed indoors in groups of two or three individuals. The level of interaction during routine care and management (ie in the process of cleaning, feeding, and monitoring) represented the baseline condition. The test condition involved a familiar caretaker spending an additional 10 mins per day, 5 days a week, with each chimpanzee. This study was designed to assess carry-over effects of interaction on behaviour outside the context of care staff presence. Therefore, in all phases of the study, data (97 h of focal animal sampling) were collected only when caretakers were absent from the building. During the increased human interaction phase, the chimpanzees groomed each other more and showed lower levels of the following behaviours: regurgitation/reingestion, other oral abnormal behaviours, inactivity, and reactivity to the displays of neighbouring groups. A trend towards reduced agonistic display was also detected. Attempted interactions with the observer shifted significantly from predominantly aggressive to predominantly affiliative in nature. These results suggest that simple, unstructured affiliation between humans and chimpanzees should be a valued component of behavioural management.