While the zoological community strives to provide the best possible living environment for non-human animals, space limitations constrain where zoos can house particular species. Therefore, an individual may live in proximity to animals that impact its behaviour, physiology, reproductive function or overall welfare status. This article examines how solitary and social species living in managed settings are positively and negatively affected by conspecific neighbours. When making housing decisions, zoos should follow husbandry recommendations outlined by zoo associations, integrate natural history information and attempt to view the environment from the perspective of the species of interest. Furthermore, researchers can collect survey, behavioural and physiological data to examine how variables, such as density, distance between neighbours, the age/sex of conspecifics and types/amount of exposure to others influence welfare. Ultimately, zoos should consider the needs of individuals and investigate whether welfare can be enhanced by modifying enclosures, husbandry routines, enrichment schedules or access to conspecifics. A zoo's willingness to alter an animal's exposure to conspecifics may have a substantial impact on physical, mental and emotional health.

Antimicrobial resistance is a major threat to both human and animal health, but reduction of use raises issues of how standards of animal health and welfare can be maintained without them. This turns the spotlight onto the role of good management and higher standards of animal welfare as drug-free ways of improving immune function and increasing resistance to infection. Research is urgently needed into the relationship between animal welfare, immunity, gut microbiota and disease and we are not yet in a position to claim that improving welfare will improve resistance to disease. ‘Boosting’ the immune system is not straightforward and an interdisciplinary approach is needed.

A collaborative effort was undertaken to delineate underwater noise levels within holding enclosures at marine mammal facilities. Ambient noise levels were measured under normal operating conditions in the enclosures of 14 participating facilities. Facility habitats varied from ocean environments to fully enclosed pools. The means and standard errors of the noise pressure spectral densities measured across all pools were similar to those measured in natural coastal environments with relatively low presence of anthropogenic noise. Highest levels of noise in land-based pools were generally at frequencies < 2 kHz and primarily due to the operation of water treatment/filtration systems. Noise levels in land-based pools were comparable to or lower than semi-natural and natural systems at higher frequencies because of the presence of biological noise sources in these systems (eg snapping shrimp [Alpheus spp]). For odontocete enclosures, the whales themselves were often the greatest source of sound at frequencies where the whales have their best hearing (~40-100 kHz). The potential for facility ambient noise to acoustically mask odontocete communication signals and echolocation clicks appears to be low. In general, when noise was elevated it was at frequencies outside the typical frequency ranges of whistles and echolocation clicks, and where odontocetes have poor hearing sensitivity. Occasional noise issues were found; it is therefore recommended that facilities periodically assess enclosure noise conditions to optimise animal management and welfare.

Animal welfare scientists actively seek reliable and practical metrics that can serve as indicators of animal welfare for use with agricultural, laboratory and zoo-housed animals. Behavioural diversity as a welfare concept originated from early welfare scientists linking poor animal welfare with a high proportion of time spent engaged in stereotyped behaviours and little expression of behaviours that would be expected under wild, or natural conditions. Recently, the concept of behavioural diversity as a welfare indicator has been widely adopted and is frequently quantified by the Shannon-Wiener Diversity Index (H-index). However, the H-Index is fraught with theoretical and mathematical limitations when applied to animal welfare. Four key problems with this metric are demonstrated: the metric's responsivity to the size of the behavioural repertoire and the underlying assumption that larger behavioural repertoires reflect better welfare, the sensitivity of the metric to arbitrary decisions about the resolution of behavioural categories, the fact that the calculation of the metric is agnostic to the valence of behaviours, and the metric's susceptibility to the common practice of excluding some behavioural categories. Moving forward, we recommend focusing on validated welfare measures that are sensitive to valence when evaluating animal welfare.

Muslims derive their dietary laws from the Quran (Islamic Holy Book) and other Islamic scriptures. These religious scriptures prohibit them from consuming meat from animals that die before they are bled-out. Some Muslim authorities have interpreted this to mean that, in addition to the animal being alive, it must also be conscious prior to neck-cutting. This has led to a section of the Muslim community rejecting pre-slaughter stunning for halal meat production with the belief that all forms of stunning lead to instantaneous death. It must be noted that some jurists have debunked claims that animals must be conscious before they are bled-out because it does not appear to be mentioned anywhere in the scriptures. This paper reviews literature on the role of the brain in the control of conscious perception and death and considers the different scholarly definitions of death and how they impact the interpretation of halal slaughter rules and the impact on animal welfare.

Previous work surveying equine professionals has suggested ignorance to be a primary cause of poor welfare within the industry, highlighting the importance of improving educational opportunities for industry stakeholders. This may be achieved through on-farm assessments designed to evaluate facilities and share resources with farm owners. While used extensively for evaluating production animal facilities, equine facilities are rarely formally assessed, making it important to determine how well those assessments would be received by equine owners and managers. As part of a larger project, an on-farm equine welfare assessment tool was pilot-tested on a sample of diverse horse farms (n = 26). Farm managers completed a self-assessment to determine their perception of their own farms with respect to animal welfare and then participated in the on-farm assessment process. Post-assessment interviews allowed participants to provide feedback regarding their experience. Farm managers most often underestimated the prevalence of structural issues in their facilities but were more discerning in management-related elements (eg stall cleanliness). Descriptive analysis indicated that farm managers felt that the on-farm assessment tool had the potential to be useful to newcomers to the industry and for a certification programme. Participants also highlighted areas that could make enforcing welfare standards an issue, such as horse and farm ownership. Understanding the perception of on-farm assessments is useful to gauge the potential success of animal care assessment programmes. If well-received, an industry-driven, on-farm welfare assessment has the potential to better educate horse farm managers and, by extension, improve the welfare of the animals under their care.

Stereotypies are frequently associated with sub-optimal captive environments and are used as welfare indicators. However, susceptibility to stereotypy can vary across individuals of the same group. As such, identifying which individuals are more susceptible to this behaviour may be helpful in managing this issue. We have investigated which sex-age class of semi-captive capuchin monkeys (Sapajus spp) is more susceptible to stereotypic behaviours and evaluated whether or not they are also more affected by the social factors that typically influence and increase allostatic load. To accomplish this, we used instantaneous sampling to collect data on a group of capuchins kept on an island in an urban park in São Paulo, Brazil. We found that sub-adult males were the only sex-age class to display stereotypic behaviours and they all displayed pacing. Furthermore, 33% of sub-adult males also exhibited a second stereotypic behaviour associated with their pacing. Compared to the other sex-age classes, sub-adult males had a higher participation in social conflicts and experienced higher social isolation. Sub-adult males also demonstrated a lower level of positive social interactions. All of these factors typically increase allostatic load. We suggest that distal causation of the observed pacing behaviour would be the ecological/evolutionary need of sub-adult males to disperse from their natal group and that the proximal causation would relate to the high allostatic load from social sources. We recommend that managers of zoos and other facilities monitor changes in the social composition of captive groups and evaluate individuals’ age so that necessary alterations may be made, where appropriate, to reduce allostatic load and generate better welfare at individual and group levels.

Laboratory animals need to be monitored to check the status of their health and welfare. Routine checks of laboratory fish are limited to visual observations of physical appearance and behaviour, but for species held in opaque-walled tanks, such checks are compromised by restricted views, poor visibility and provoked behaviour. Here, we report our experience of using in-tank underwater cameras to monitor laboratory populations of salmoniforme, perciforme and cypriniforme fish. A range of cameras and lenses were investigated and trialled. A standard VGA resolution analogue camera with a one-third-inch chip and 3.6-mm lens was selected based on size, picture quality, the proportion of tank in view and cost. A shell for the camera and mounting system were designed to minimise size and cleaning and enable flexible positioning within tanks. Cameras were connected via digital encoders to a server, making video available to the general computer network. Data collected from recordings of rainbow trout (Oncorhynchus mykiss) confirmed provoked behaviour, ie a change in distribution and increase in activity in response to direct viewing and feeding. The networked cameras therefore enable remote viewing of undisturbed behaviour in real time, providing clear, lateral views unaffected by water surface effects, and facilitate increased frequency of checking. Case studies illustrate how camera monitoring can aid detection of abnormalities in behaviour (eg lack of feeding, posture, swimming) and appearance (eg clinical signs, such as lesions), enabling earlier interventions. Furthermore, recordings provide a resource for reference and retrospective analysis, and evidence to support severity classification and identify humane end-points.

Preferences for the height of feeding troughs of seven mares were evaluated and, as awareness of surroundings when feeding is adaptive for horses, the relationship between preference responses and attention behaviours was also assessed. First, feeding troughs at four heights (0, 25, 50, and 75 cm) were provided for 16 days, and the amount of time animals ate from each height option was measured daily. These data were used to determine the preferred/non-preferred options for each individual. An overall preference for heights of 50 and 75 cm was detected, but responses showed significant individual variation The same animals were subsequently observed, when feeding from preferred (four days) or non-preferred (four days) trough heights, while their behaviours were recorded. Moving ears/head (attention behaviours) occurred more frequently when feeding from preferred heights of feeding troughs. We concluded that to ensure better welfare conditions for the mares in this study, it was important to consider the individual variation of such preferences if possible, however, by using troughs positioned at 50 or 75 cm, the general preference could be assured. Moreover, when feeding from their preferred heights, the study mares paid more attention to their surroundings than when feeding from their non-preferred height and thus it is likely that they defended their preferred options more. However, further studies are needed to evaluate the generalisability of these findings. We have demonstrated a methodology to assess mares’ preferences and provided some preliminary data on the relationship between preferences/non-preferences and the possible emotional states of mares.

Leg problems are highly prevalent in modern broiler production and provision of environmental enrichment could be a strategy to improve leg health. Different types of environmental enrichment have undergone evaluation. Our objective was to conduct a systematic review of the effect of environmental enrichment on leg health in broiler chickens. The evaluation of leg health included measures of the entire leg and foot, and behavioural, pathological and physical measures. Six types of environmental enrichment were selected for inclusion: light programme, intensity of light, stocking density, perches, straw bales and separation of resources. For each type, a systematic literature search was performed. The review included 62 studies; 56 randomised trials and six cross-sectional studies. An assessment of the methodological quality of all 56 randomised trials was performed with some reporting deficits regarding occurrence of blinding, randomisation and reliability of measures. Provision of perches and increased intensity of light only displayed limited effectiveness in improving leg health and both mainly affected contact dermatitis. In contrast, there was evidence that a lowered stocking density and a dark/light schedule could improve leg health. Few studies have been carried out on the effect of straw bales and separation of resources. The few studies done have, however, shown that both types of enrichment can be effective in improving leg health. In conclusion, identifying and providing the optimal types of enrichment for broilers will reduce leg problems and increase mobility, thereby improving the welfare of the birds.