The provision of foraging opportunities may be a simple way of improving an animal's welfare, but this approach has been neglected for laboratory rats (Rattus norvegicus). Standard housing contains little enrichment, and food is often provided ad libitum, which may result in inactivity and obesity, especially in mature males. Foraging enrichments may offer a way to correct these deficiencies. This study compared three potential enrichments — a limited-access hopper, gnawing sticks and a foraging device — to standard housing and feeding conditions, in order to examine their effects on rat body weight, food consumption, behaviour and preferences. The subjects were 12 mature male Wistar rats. Effects were assessed from daily weighing and from video records of the rats' behaviour over 24 h periods. The rats' preferences were determined using a four-way test system in which they could choose between a standard cage and cages offering the three potential enrichments. Compared to the standard housing and feeding, the limited-access hopper had a tendency to reduce food consumption, but the time spent feeding increased. The gnawing sticks provided the rats with the opportunity to gnaw, but did not affect other behaviours or body weight. The foraging device had the benefits of reducing aggression and allowing the rats to search for and manipulate food, but resulted in significant gains in body weight. Additionally, the foraging device was the preferred feeding source. Of the four possible feeding locations, the rats spent the least amount of time in the standard cage. The foraging device provided the most benefits but requires further modification to address problems of obesity.

Spatial restriction and low cage height can reduce the rate at which comfort activities, such as wing flaps, stretching, body shakes and tail wags, are carried out by laying hens in conventional wire cages. In this study we investigated the performance of these activities in laying hens housed in furnished cages with perches and nest boxes, similar to those required in EU legislation from 2012. We compared the behaviour of groups of eight hens at a stocking density of 762 cm2 per bird with that of pairs of hens housed at a lower stocking density of 3048 cm2 per bird at two minimum cage heights of 38 cm and 45 cm. The rates of wing/leg stretches (0.80 stretches per hen per hour), tail wagging (0.76), body shaking (0.48), wing raising (0.19) and feather raising (0.05) were low, whilst full wing flaps were not observed during the study. Hourly rates of performance of wing/leg stretches (0.45 vs 1.06) and tail wags (0.34 vs 1.25) were significantly lower in eight-bird cages than in two-bird cages. We conclude that reducing the number of hens in furnished cages increases opportunities to perform certain comfort activities, but that, even at low stocking densities, comfort activities are rarely observed.

The use of demand functions to identify the behaviours most important to animals has been advocated widely. The principle is to place increasing cost on the opportunity to perform several behaviours and subsequently to rank these behaviours according to the change in their performance as a function of cost; this change is described by the elasticity of the demand function. However, the method has been criticised for placing the animal in too artificial a setting. Firstly, the animal works repeatedly for short periods of access to a resource, which may interrupt bouts of behaviour; secondly, animals are tested in isolation, which may affect their motivation to perform the target behaviour; and, finally, assumptions regarding the effect of prior deprivation and reward duration on elasticity of demand need to be tested. This criticism, however, is important only if these factors do affect the elasticity of the resulting demand function. This paper reviews experiments that have developed methods to assess the importance of various behaviours to farm animals and that have tested the effect of social context, length of deprivation of a resource and reward duration. It is concluded that the elasticity of demand function may be used to assess the relative importance of various behaviours, but that it is important to make sure that the experimental set-up yields valid estimates of the elasticity of demand.

Tests of emotionality conducted outside the home-cage show that rodents from standard laboratory housing are more anxious than animals from enriched housing; however, it is not known if this also indicates increased anxiety within the home-cage. We used a novel method, recording the self-administration of a psychoactive anxiolytic, to examine home-cage anxiety levels of laboratory mice (three per cage) in Standard (n = 10 cages), Unpredictable (n = 10 cages) and Enriched (n = 6 cages) housing. The mice were given a choice of drinking either non-drugged water or a solution of the benzodiazepine Midazolam. There was a significant effect of housing on the proportion of total fluid consumed from the bottle containing Midazolam solution (P = 0.02). Mice from Standard and Unpredictable cages drank a greater proportion than mice from Enriched cages. This indicates that mice from the Standard and Unpredictable laboratory caging may have been experiencing greater anxiety than mice from the Enriched cages. There was also a significant effect of bottle position (P = 0.002). Mice from the Standard and Unpredictable cages drank a greater proportion of total fluid from the bottle containing Midazolam solution when this was toward the rear of the cage rack, ie in a location that was less susceptible to extraneous disturbance. Monitoring self-administration of psychoactive drugs as a method of welfare assessment could be applied to a wide variety of housing conditions, husbandry practices, or experimental procedures that putatively induce negative mental states. The major finding is that standard cages for laboratory rodents may induce greater anxiety than enriched cages. This is discussed in terms of animal welfare and the validity of data from animals housed in minimalistic environments.

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.

Theoretical models are presented of the effects of space, facilities and group size on the behaviour of chickens at high stocking densities, with relevance for all animals. The appropriateness of each model is supported by published data, although such data are scant for some important variables. Freedom of movement is analysed by taking the area of a hen as 475 cm2 and finding the number of free bird spaces left at different space allowances. This provides support for current recommendations of a maximum of seven laying hens per m2 on deep litter, but suggests that a maximum for broilers of 34 kg/m2 unacceptably restricts freedom of movement. In cages, freedom of movement increases with space allowance per hen, and, for a given space allowance, with cage and group size. Nesting behaviour is analysed for synchrony, which decreases with group size. Perching and feeding are often synchronous and the space needed for these is determined by body width. Recommendations are derived for hens in furnished cages. The main part of the cage should be as large as possible; an absolute minimum of 600 cm2 per bird is suggested, but 675 cm2 per bird is probably the minimum practical. Perch and feeder space should be provided at 14 cm or more per bird, with a possible derogation for light hybrids to 12 cm. The number of nest spaces needed varies with the number of birds, with nest spaces being 300 cm2 each. These recommendations sum to a minimum of 800 cm2 per bird for groups of eight or more, 850 cm2 for groups of four to seven, and 900 cm2 for groups of three or fewer, plus litter area. Crowding is primarily caused by limited space allowance, but for a given space allowance it is worse in small enclosures and groups.

One hundred and twenty-eight pigs were reared in barren or enriched environments from birth to slaughter at 21 weeks of age. Pigs remained as litter-mate groups until 8 weeks of age when they were mixed into groups of eight animals. These groups were balanced for gender and weight and contained two pigs from each of four different litters. Each pig was assigned high or low social status on the basis of relative success in aggressive interactions at mixing. Injury levels were assessed on a weekly basis from 8 to 21 weeks of age. Pigs were exposed to two group food competition tests after a period of food restriction at 10 weeks of age, and to an individual novel pen test at 11 weeks of age. Behavioural and plasma cortisol responses to both types of test were recorded. Low social status was associated with increased injuries to the head, neck and ears, and therefore reduced welfare. Pigs with low social status showed reduced resource-holding ability in the food competition test, and greater avoidance of a novel object during the novel pen test It is suggested that avoidance of the novel object reflected ‘learned’ fearfulness in these individuals. Environmental enrichment did not negate the effect of low social status on injury levels, but did appear to reduce the negative influence of low social status on stress during food restriction, and led to a reduction in fearfulness in response to the novel pen test. These results suggest that environmental enrichment may improve the welfare of growing pigs with low social status.

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.

Responses to potential threats to welfare vary greatly between species. Even closely related animals often differ in their fear of humans and/or novelty; their behavioural responses to pain; and when captive, their overall welfare and the form and frequency of their stereotypies. Such species differences stimulate hypotheses about I) the way that responses to challenge co-vary with other biological traits; 2) the adaptive value of particular responses; and 3) the factors predicting responses to evolutionarily new scenarios, such as captivity. We illustrate how these ideas can be statistically tested with multi-species comparisons, and show how techniques such as the Comparative Analysis of Independent Contrasts can be used to control for any non-independence of data points caused by species’ relatedness. For each of the three types of hypothesis, we then provide several welfare-relevant examples including one that has been fully tested (respectively, the relationships between sociality and anti-predator behaviour in antelopes; predation pressure, foraging niche and neophobia in parrots; and home range size and stereotypy in carnivores). Ultimate explanations such as these, based on species’ ecology and evolutionary history, have great explanatory appeal. Species comparisons can also have great practical value, allowing the test of hypotheses that would be almost impossible to investigate experimentally, and generating principles that allow predictions about the welfare of similar unstudied species. Multi-species data, for example from the many taxa held in zoos, thus hold enormous potential for increasing the fundamental understanding of animal welfare.

The behaviour and serum Cortisol concentrations of three captive female African elephants (Loxodonta africana) were studied to determine whether their stereotypic swaying was more prevalent before regularly scheduled events in the elephants’ routine, and whether the elephants that exhibited more stereotyped swaying had lower mean serum cortisol concentrations. Behavioural data were collected during hour-long observations balanced across three periods, and during 15-min observations prior to the elephants being moved to different portions of their enclosure. Observational data were collected using instantaneous focal sampling of behaviours every 30s. Serum cortisol measures were obtained through weekly blood withdrawal from the elephants’ ears. Of the three elephants, two exhibited stereotyped swaying, which accounted for a mean of 0.4% of the scans during the hour-long observations and a mean of 18% of the scans prior to the elephants being moved between different parts of the enclosure. Swaying was highly variable among the individual elephants during both categories of observations. Additionally, both elephants swayed more prior to moving in the afternoon than prior to moving in the morning. Analyses of serum cortisol concentrations indicated that each elephant had a different mean cortisol level, which did not clearly correspond with the expression of swaying. The findings indicate that a rigidly scheduled management event may elicit stereotyped swaying in the studied elephants. Future research should document the behavioural and physiological effects of an altered management routine to improve captive elephant welfare.

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.

Studies of the brain inform us about the cognitive abilities of animals and hence affect the extent to which animals of that species are respected. However, they can also tell us how an individual is likely to be perceiving, attending to, evaluating, coping with, enjoying, or disturbed by its environment, and so can give direct information about welfare. In studies of welfare, we are especially interested in how an individual feels. Since this depends upon high-level brain processing, we have to investigate brain function. Brain correlates of preferred social, sexual and parental situations include elevated oxytocin in the para-ventricular nucleus of the hypothalamus. Abnormal behaviour may have brain correlates, for example, high frequencies of stereotypy are associated with down-regulated μ and κ receptors and dopamine depletion in the frontal cortex. Such results help in evaluating the effects of treatment on welfare. Some brain changes, such as increased glucocorticoid receptors in the frontal lobes or increased activity in the amygdala, may be a sensitive indicator of perceived emergency. Active immunological defences lead to cytokine production in the brain, vagal nerve activity and sickness effects. Some aspects of brain function can be temporarily suppressed, for example, by opioids when there is severe pain, or permanently impaired, for example, in severely impoverished environments or during depression. Coping attempts or environmental impact can lead to injury to the brain, damage to hippocampal neurons, remodelling of dendrites in the hippocampus, or to other brain disorganisation. Brain measures can explain the nature and magnitude of many effects on welfare.

Blindfolding is routinely used to aid the handling and loading of horses that are difficult to control. Fifteen relatively well-behaved horses of varying ages and disciplines were used to investigate the effects of blinkering and blindfolding on behaviour and heart rate in three situations: whilst stabled, when being led in a ménage, and during loading onto a lorry. Heart rate increased in all three situations when a blindfold was used, and when animals were handled by the least experienced of three handlers. The effects of blinkering on heart rate and behaviour were small compared with blindfolding. Overall, blindfolding appeared to make the horses more nervous and difficult to handle. However, the study does not discount the practical application that blindfolding may have for improving welfare and safety when handling certain individual horses. This work forms the basis for further studies involving animals less accustomed or disposed to being handled.

The aim of this study was to assess the extent to which three non-invasive measures of welfare in laying hens (egg-shell quality, corticosteroid levels as measured from the birds' faeces, and behavioural preferences) were correlated over a period of five days in two groups of birds. One group had access to an enriched test area (bark chips on the floor and a tray of sprouted wheat); the other group had access to a comparably sized barren area (bare wire mesh floor). The measure of preference used was the amount of time hens spent in the test area as measured each day. It was predicted that birds with access to the less preferred environment would show higher levels of faecal corticosteroids and egg-shell anomalies. However, although the birds showed a preference for the enriched environment from Day 1, the other two measures did not follow the same pattern. Faecal corticosteroid metabolites showed an initial increase in both groups, which declined significantly by Day 4, with the ‘enriched’ birds in fact showing a trend for higher levels than the ‘barren’ birds. Shell thickness also showed a change over the five days, but with a different time course: declining to a minimal level on Day 3 and then rising again by Day 5. No measure of shell quality was significantly different between the two environments, but there was a trend for changes in shell thickness to be more pronounced in eggs from enriched birds. The results indicate the caution that needs to be exercised in using shell quality or corticosteroid measurements in isolation from assessments of what the animals themselves prefer.

During summer and autumn of 1994-1997, we determined the movements and mortality of 38 adult male Eastern grey squirrels (Sciurus carolinensis) that had been captured in urban-suburban backyards and translocated to a large forest. The squirrels did not fare well. Squirrels not found dead or classified as ‘probable mortality’ disappeared from the forest with a median time to disappearance of II days. Ninety-seven per cent (37 of 38) of the squirrels either died or disappeared from the release area within 88 days.

In recent years, consumer demand studies have been used to objectively quantify the value that captive animals place on environmental resources. Considerable progress has been made in the development of effective methodologies to assess what resources are valued under controlled experimental conditions, but few of the findings from these studies have been implemented in commercial husbandry systems. A major obstacle has been the need to maintain internal validity in experimental studies at the possible expense of external validity. Experimental subjects may be poor representatives of commercially kept animals, especially where there is no replication of the animal's experience of commercial physical and social environments. This paper will discuss means of increasing the external validity of consumer demand studies. Firstly, experimental animals should be of representative genotypes, reared under commercial conditions and housed in test apparatus with free access to all of the resources that are normally available under commercial husbandry conditions. As well as providing a long-term closed economy, this allows manipulation of potentially important environmental factors such as prior experience. Secondly, naturalistic tasks should, where possible, be used in preference to abstract operant tasks since they appear to be easier to train animals to associate with rewarding resources, therefore many individuals can be investigated efficiently. Furthermore, naturalistic tasks appear to be less prone to operant bias than artificial tasks and can provide robust measures of value in terms of the maximum price paid for access to resources. Finally, for group-housed species, social costs such as enduring higher stocking densities and/or competition for resources may be an effective means of investigating cost-benefit trade-offs under commercial conditions. For example, if animals work to evenly distribute themselves over available space, this social spacing priority can be used to investigate whether they will endure higher stocking densities in order to exploit particular resources.

The aim of this study was to assess optimal temperature ranges for fattening pigs of different weights kept in pens with partially slatted floors. We examined the behavioural and adrenocortical responses of pigs of different weights (25–35 kg, 50–70 kg, and >85 kg) to a wide range of ambient temperatures (2–29°C). On three days of each experimental period, we took saliva samples for the analysis of cortisol concentration, and recorded lying behaviour from 0800–0600h. Behavioural and cortisol parameters were analysed using linear mixed effects models. Optimal temperature ranges for the three weight-classes were calculated using logistic regression. Pigs chose different areas for resting depending on ambient temperature. With increasing temperature, pigs used the dung area more often and lay more often without contact with pen mates. Compared to lighter pigs, heavier pigs lay without contact with pen mates at lower temperatures. In general, lying without contact occurred at temperatures 5–7°C lower than lying in the dung area. Huddling increased with decreasing temperature, and, with increasing weight, pigs showed huddling at lower temperatures. There was a significant increase in cortisol levels at high ambient temperatures in pigs >85 kg. In pens with partially slatted floors, the results indicate temperature ranges within the thermal tolerance of pigs to be 19–21°C for pigs weighing 25–35 kg (lying area of 0.46 m2/pig), 10–17°C for pigs between 50–70 kg and 5–17°C for pigs >85 kg (both weights: lying area of 0.67 m2/pig).

Current procedures for ranching and sustainable use of guanacos necessitate their transport. Transportation is a risky process for animals, and is a particular concern for wild-caught or semi-domesticated species such as the guanaco — a wild South American camelid species increasingly being established on farms in Chile and Argentina. This study investigated the effect of transport on the physiological and behavioural responses of eight castrated adult male guanacos, transported on a single 2 h journey at a stocking density of 113.5 kg m-2 (0.76 m2 per animal). Plasma cortisol and blood glucose concentration, total and differential white blood cell (WBC) counts, heart rate, and body weight were measured one week before, immediately before, immediately after, 2 h after and one week after transport. Behavioural responses were recorded during handling prior to loading. Immediately after transport we found significant increases in plasma cortisol concentrations and neutrophil:lymphocyte (N:L) ratio, the latter peaking 2 h after transport. Heart rate increased significantly only during loading, while body weight remained constant throughout. Behavioural responses related to handling (jumping, vocalising, kicking, spitting and urinating) were not associated with the physiological response. All variables returned to pre-transport values within one week. Transport of guanacos under these conditions produced physiological changes similar to those associated with a mild and transient stress response in other species and which, we judge, fall comfortably within acceptable limits for their welfare.

Six veterinary practices participated in a study of cats involved in road accidents. Of 127 cats, 93 survived, of which 58 had moderate to very severe injuries. The mean period of hospitalisation was five days and the mean length of veterinary treatment was 23 days. The cost of treatment was less than £400 for 84% of cats. Owners of 51 surviving cats completed questionnaires within three to five months of the accident. The mean time it took for their cats to recover was 47 days (n = 41; range 1-150 days). Eight cats had not recovered within five months, four of which had had a limb amputated. The severity of the cats’ injuries correlated positively with the cost of treatment, length of hospitalisation and treatment, and time to recovery (rs > 0.69, P < 0.001). Behavioural changes were noted in 34 cats; 23 were described as being more nervous, going outdoors less, or being more fearful of cars, roads or going outdoors. Half of the owners treated their cat differently: 17 restricted the time their cat spent outdoors and II worried more about their cat. The effects of the accident on the owner's emotions and finances were measured using a scale from I (minimum) to 7 (maximum). Most owners registered a score of 5, 6 or 7 for effect on emotions and I, 2 or 4 for effect on finances; the scores were not correlated. Road accidents are an important cause of poor welfare in cats and their owners.

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.