We report on the efficacy of body weight change as a measure of trapping and handling stress in two species of wild small mammal: bank voles (Clethrionomys glareolus) and wood mice (Apodemus sylvaticus). We tested two hypotheses: (1) that weight change after capture and handling is related to the intensity of the trapping and handling regime, and (2) that weight change after an intensive handling regime is related to an individual's current pattern of energy expenditure. Trapped wood mice that were subjected to intensive handling (intensive stressor) lost more weight than did animals that were handled minimally (less intensive stressor), but this was not the case for bank voles. Patterns and factors related to body weight change in response to intensive handling also differed between the two species: heavier and non-breeding bank voles were more likely to lose weight, but this was not true for wood mice, and none of the factors we measured was found to affect weight loss in this species. Our results were broadly consistent with the predictions of the biological cost hypothesis. We discuss the limitations and benefits of weight loss as a measure of stress.

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 motivation of juvenile rabbits to graze was tested by offering a choice of coarse mix or grass as rewards to rabbits fed a nutritionally adequate diet of carrots and hay. Before measuring the motivation of the 16 rabbits, eight were offered access to grass for 16 days and the remaining eight were kept in outdoor hutches. An initial preference test was then conducted using a Y-maze apparatus, in which the rabbits were offered a choice of grass or coarse mix for 3 min. The rabbits that had not previously been offered grass had a strong preference for the grass reward, whereas those that had chose coarse mix and grass equally. Measurement of rabbits’ behaviour during the reward period revealed that rabbits spent longer eating if their reward was grass; this difference was particularly notable toward the end of the 3 min period. If they received a coarse mix reward, they spent more of the 3 min self-grooming, standing still and chewing the wire of the cage. Feeding rabbits with a coarse mix diet may therefore increase the likelihood of problem behaviours including inactivity and trichophagia. The rabbits were also trained in a novel operant test of motivation for the two rewards, in which they were required to circumnavigate an object several times before receiving a reward. The number of circumnavigations before a reward was offered was progressively increased, and rabbits were offered two opportunities to take the reward at each level. Although the rabbits were prepared to circumnavigate the object up to II times on average, there was little evidence that they would work harder for a grass reward than for a coarse mix reward. This may have been because they had previously had experience of grass during the preference tests. It is concluded that juvenile rabbits show a strong initial preference for a grass reward, compared with coarse mix, but that this preference disappears after brief exposure to grass. There was no strong evidence that rabbits will work harder to receive a grass reward than to receive a coarse mix reward.

We estimate that stereotypies are currently displayed by over 85 million farm, laboratory and zoo animals worldwide. This paper investigates their reliability as welfare indicators, by surveying studies relating stereotypy to other welfare measures and by analysing the mechanisms underlying this behaviour. Where data exist, most (approximately 68%) situations that cause/increase stereotypies also decrease welfare. Stereotypy-eliciting situations are thus likely to be poor for welfare, although exceptions exist. Within such an environment, however, most (approximately 60%) accounts link individual stereotypy performance with improved welfare (cf approximately 20% linking it with reduced welfare). Thus, in a sub-optimal environment, non-stereotyping or low-stereotyping individuals could well have the poorest welfare, although again exceptions exist. Examining the mechanisms underlying stereotypy performance, we discuss four processes that could account for these complex links between stereotypy and welfare. Beneficial consequences from performing the specific source-behaviour of the stereotypy (‘do-it-yourself enrichment’), or arising from repetition per se (‘mantra effects’), may ameliorate welfare in poor environments. In addition, stereotypies that have become centrally controlled (habit-like), or that arise from autistic-like changes in the control of all behaviour (perseveration), are likely to be unreliable indicators of current state because they can be elicited by, or persist in, circumstances that improve welfare. To refine the role of stereotypy in welfare assessment, we suggest the collection of specific additional data to reveal when any of these four processes is acting. Until such research increases our understanding, stereotypies should always be taken seriously as a warning sign of potential suffering, but never used as the sole index of welfare; non-stereotyping or low-stereotyping individuals should not be overlooked or assumed to be faring well; simple measures of frequency should not be used to compare stereotypies that differ in age, form, or the biological or experiential characteristics of the performing animal; enrichments that do not immediately reduce stereotypies should not be assumed failures with respect to welfare; and finally, stereotypies should not be reduced by means other than tackling their underlying motivations.

The study of environmental enrichment has identified a variety of effective forms of enrichment, but there are widespread problems associated with their use. Few forms of enrichment are cognitively challenging, and even the most effective often result in rapid habituation. This study examined the use of a computer-joystick system, designed to increase in complexity with learning, as a potential form of enrichment. Eight orangutans (Pongo pygmaeus), housed in male/female pairs, were observed for 120 h during a baseline period and 120h when the computer-joystick apparatus was available. Data were collected in 1 h sessions using instantaneous group scan sampling with 30 s intervals. The orangutans spent 25.9% of the scans using the joystick system. One member of each pair monopolised the computer system: ‘high users’ spent 48.9% of scans using the joystick system compared with 2.9% by ‘low users’. Behavioural changes associated with the provision of the computer included increases in aggressive behaviour, anxiety-related behaviours, solitary play, contact with and proximity to a social partner, and decreases in feeding. The lack of habituation by the high users, both within and across sessions, indicates that computer-assisted tasks may be a useful form of environmental enrichment for orangutans. However, the significant increase in aggression indicates that this form of enrichment may be more suitable for singly caged animals, or that the provision of multiple apparatuses should be tested for the ability to eliminate potential competition over the device.

Our ability to assess pain in animals in clinical situations is slowly developing, but remains very limited. In order to develop appropriate pain scoring schemes, numerous practical problems need to be overcome. In addition, we need to appraise realistically our current poor state of knowledge. Development of new scoring systems must be coupled with the increased education and training of those responsible for pain management, so that both the assessment and the alleviation of pain are steadily improved.

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.

Historically, pet dogs were trained using mainly negative reinforcement or punishment, but positive reinforcement using rewards has recently become more popular. The methods used may have different impacts on the dogs’ welfare. We distributed a questionnaire to 364 dog owners in order to examine the relative effectiveness of different training methods and their effects upon a pet dog's behaviour. When asked how they trained their dog on seven basic tasks, 66% reported using vocal punishment, 12% used physical punishment, 60% praise (social reward), 51% food rewards and II% play. The owner's ratings for their dog's obedience during eight tasks correlated positively with the number of tasks which they trained using rewards (P< 0.01), but not using punishment (P = 0.5). When asked whether their dog exhibited any of 16 common problematic behaviours, the number of problems reported by the owners correlated with the number of tasks for which their dog was trained using punishment (P< 0.001), but not using rewards (P = 0.17). Exhibition of problematic behaviours may be indicative of compromised welfare, because such behaviours can be caused by— or result in — a state of anxiety and may lead to a dog being relinquished or abandoned. Because punishment was associated with an increased incidence of problematic behaviours, we conclude that it may represent a welfare concern without concurrent benefits in obedience. We suggest that positive training methods may be more useful to the pet-owning community.

The objective of this project was to collect scientific data to assist in the development of guidelines for the humane relocation of threatened and endangered arboreal non-human primate species. A troop of 31 Lowland Sykes monkeys (Cercopithecus mitis albotorquatus) was habituated to fruit bait for capture in a village and relocation to a previously selected suitable site in a protected forest reserve approximately 30 km away. Sixty-five percent (n = 20) of the animals were captured and relocated. This subgroup comprised one adult male, eight adult females, two subadult females, three juvenile males, four juvenile females and two infant males. Although the relocated group originated from one single group, post-translocation telemetry signals demonstrated that it split into two groups, which established themselves approximately 2–4 km apart in their new territory; the adult male eventually became solitary. The factors of importance for the successful capture and relocation of forest primates were found to include: proper understanding of troop home-range utilisation and of social bond organisation within the troop, method and period of habituation, method of release, suitability of the new habitat with respect to the ecological niche requirements of the species in question, and the period of post-relocation monitoring.

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.

The objective was to evaluate the welfare implications of electrical stunning prior to gill-cutting of farmed African catfish as an alternative to live chilling in combination with gutting. Electroencephalogram (EEG) and electrocardiogram (ECG) recordings, in combination with observation of behaviour and responses to noxious stimuli, were used to assess brain and cardiac function in African catfish (body-weight 1571 ± 362 g [mean ± standard deviation], 32 males and 26 females). In the first experiment, the minimum electrical current required to induce a general epileptiform insult by head-only stunning was determined. The individual catfish were fixed in a specially designed restrainer, and applied voltages of 150 V, 200 V, 250 V, 300 V or 350 V (50 Hz AC) were delivered via scissor-model stunning tongs for approximately I s. A general epileptiform insult was observed in 31 fish, for which a successful EEG recording was obtained using 362 ± 32 V, 629 ± 180 mA for 1.2 s. The durations of the tonic, the clonic and the exhaustion phases were 8 ± 3 s, 12 ± 7 s and 7 ± 5 s as measured by EEG, respectively; a distinct exhaustion phase was not clear in II fish. The total duration of the insult was 23 ± 8 s. After the insult the fish recovered. The heart rate was 63 ± 29 beats min I prior to stunning. After stunning, the ECG revealed extrasystole and was irregular. By using an average current of 629 ± 180 mA (at approximately 360 V, 50 Hz AC), at least 91% of fish are effectively stunned with a confidence level of 95%. In the second experiment, the behaviour of 10 individual catfish, which were able to move freely in water, was observed following head-only stunning (370 V). The durations of the tonic, clonic and exhaustion phases in free-swimming fish were II ± 8 s, 20 ± 5 s and 23 ± 20 s, respectively. All fish recovered. In the third experiment, a group of seven catfish was head-only stunned followed by gill-cutting to kill them as a second procedure (ie after recovery from head-only stunning). No brain activity was seen on the EEG 12 ± 5 s after stunning. However, two fish showed responses to noxious stimuli after 2 min and 5 min. A second group of seven catfish was gill-cut only. They responded to noxious stimuli for at least 15 min. The blood loss was 1.2% and I.0% of live weight for the first and second group, respectively. It may be concluded from our results that African catfish are effectively stunned for 23 ± 8 s with a current of 629 ± 180 mA for 1.2 s, after which they recover. Since evoked responses may remain for at least 5 min after stunning and gill-cutting, we recommended that the stunning and killing procedure should be optimised.

Wild badgers (Meles meles) in Wytham woods, Oxfordshire, are routinely trapped, transported to a central field laboratory, studied and released as part of an on-going population study. These procedures have been carefully developed to minimise impact on the badgers' welfare; however they are potentially stressful, and, as part of our on-going welfare refinements, and our exploration to develop methods for quantifying stress in wild mammals, we studied the effects of transport stress on neutrophil activation in wild trapped badgers. Blood samples were obtained from 28 badgers. We compared three transport regimes: transported (n = 9), transported and rested for at least 30 mins (n = 11), and not transported (n = 8). Total and differential white cell counts were carried out and neutrophil activation was measured by the nitroblue tetrazolium test. Our goal was primarily to validate neutrophil activity as an indicator of stress, on the basis that the transport treatment was expected to be more stressful than the non-transport treatment. There were significant increases in % activated circulating neutrophils in response to transport. This study supports the proposition that stress affects circulating neutrophil numbers and the state of their activation, as determined by the nitroblue tetrazolium reduction assay, and therefore adds weight to the idea that neutrophil activation is a potential measure of stress in wild animals.

The distress experienced by animals during the induction of unconsciousness remains one of the most important and yet overlooked aspects of effective methods of anaesthesia and euthanasia. Here we show that considerable differences exist in the aversive responses elicited by 12 common methods of inhalational anaesthesia and euthanasia in laboratory rats and mice. Carbon dioxide, either alone or in combination with oxygen or argon, was found to be highly aversive to both species. The least aversive agents were halothane in rats and enflurane in mice. Exposing these animals to carbon dioxide in any form, either for anaesthesia or for euthanasia, is likely to cause considerable pain and distress and is therefore unacceptable when efficient and more humane alternatives are readily available.

Increasingly, perches for laying hens are being made from metals and plastics. There is nothing in the literature regarding how easily birds jump between perches of different materials, or how their ability to do so changes with faecal contamination of the perches. Forty-four medium hybrid brown hens negotiated perches of wood (5 cm × 5 cm, rounded edges), metal (half-round section, diameter 4 cm) or poly-vinyl-chloride (PVC: circular section, diameter 4 cm), which were either clean or dirty (poultry manure 0.5–1.0 cm deep). The time to jump to the destination perch (0.75 m from the start perch), number of squats (pre-jumping behaviour), slips, failures to jump (in 300 s) and crashes were recorded. Compared to wood and metal perches, birds took significantly longer to jump from PVC perches when they were clean, but there was no difference when the perches were dirty. Birds slipped significantly more on clean metal or PVC perches compared to clean wood perches. The birds took significantly longer to jump from metal or wooden perches when they were dirty compared to when they were clean. These data may suggest that PVC is not a suitable material for perches. Slipperiness is important. The birds apparently found the metal and PVC perch more slippery than the wooden perch, although the metal perch did not cause the birds to delay jumping. A slippery perch may deter the birds from attempting to jump. Manure on the perches reduced the slipperiness of the metal and PVC perches. Once perches become dirty, any welfare issues concerning the risk of injury from slippery perches cease to be as important as the potential slipperiness of the manure itself.

Humans interact with fish in a number of ways and the question of whether fish have the capacity to perceive pain and to suffer has recently attracted considerable attention in both scientific and public fora. Only very recently have neuroanatomical studies revealed that teleost fish possess similar pain-processing receptors to higher vertebrates. Research has also shown that fish neurophysiology and behaviour are altered in response to noxious stimulation. In the light of this evidence, and in combination with work illustrating the cognitive capacities of fish, it seems appropriate to respond to a recently published critique (Rose 2002) in which it is argued that it is not possible for fish to experience fear or pain and that, therefore, they cannot suffer. Whilst we agree with the author that fish are unlikely to perceive pain in the same way that humans do, we believe that currently available evidence indicates that fish have the capacity for pain perception and suffering. As such, it would seem timely to reflect on the implications of fish pain and suffering, and to consider what steps can be taken to ensure the welfare of the fish that we exploit.

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.

Traditionally, game-keepers and agriculturalists have controlled predators using lethal methods, but there are circumstances under which these may be ineffective or inappropriate for animal welfare or conservation reasons. Generalised aversion is potentially a form of non-lethal control, in which predators are conditioned to avoid foul-tasting bait, causing them subsequently to generalise this avoidance to similar, but untreated, prey, thereby affording it protection. In this exploratory study, a group of captive red foxes (Vulpes vulpes) was successfully conditioned to avoid untreated milk after drinking milk containing BitrexTM, a bitter substance that they were unable to detect except by taste. Our foxes were members of a family group and so housed together to reduce stress, and therefore the individuals’ responses to the various treatments may not have been independent. As a result, we combined data from the three animals, and our most conservative analyses consider the sampling population to be this fox group; we do not make inferences about foxes in general, but confine them to this fox-group. This trial was a pilot to reveal the potential for future work on wild animals. Successful application of generalised aversion to non-lethal predator control has far-reaching implications for the sport hunting industry, nature reserve management and the conservation of threatened predators requiring control, as well as clear animal welfare benefits.