In modern zoos, training should be an integral component of the animal care and management. The benefits of training include the opportunity for positive interactions with caretakers. This study was carried out with a group of vervet monkeys (Chlorocebus aethiops) housed at the Garda Zoological Park, Italy. Using focal animal sampling, we observed the behaviour performed by all group members from December 2007 to August 2008. The group took part in a training programme to be isolated in a familiar area before the subjects were included in a cognitive study. We collected behavioural data during a pre-training period to assess the social behaviour of the colony and during the training period to investigate the effects of the training programme on the behaviour of individuals. Additionally, a second phase of the study was conducted and training sessions with individual monkeys were video-recorded to determine the behaviour of animals during each training session and to thus confirm that they were suitable for participating in the procedure. Our results suggest that the training programme enriched the daily routine of these captive primates by increasing affiliative behaviours while decreasing agonistic behaviours. Furthermore, there was behavioural response variability among the individuals under the training procedure. However, all the individuals were trained to calmly enter a familiar area and be isolated from other members of the group. In conclusion, our findings highlight the importance of using positive reinforcement training to reduce the tension directly associated with potentially stressful procedures by allowing primates to participate voluntarily in these procedures. In addition, the training was found to be an enrichment tool for vervet monkeys.

Procedures that increase foraging and exploratory behaviours are generally accepted as effective at improving welfare and reducing stereotypies in captive animals. To determine the effect of food and toy enrichment on the behaviour and hormonal levels of maned wolves (Chrysocyon brachyurus), 11 wolves were submitted to a baseline-enrichment-baseline schedule with four enrichment conditions: food scattering, toy presentation, edible toy presentation, and a combination of food and toy conditions. Behaviour and glucocorticoid metabolite concentrations (GCM) were assessed throughout the experiment. Our hypotheses were that enrichment procedures would lead to an increase in activity in the short and long term, a decrease in pacing, and a reduction in GCM concentrations. We also hypothesised that the concentrations of GCM would show a correlation with behaviour. Enrichment conditions increased immediate locomotion but did not produce long-term changes of activity nor reduced pacing. The procedures had a clear effect on individual behaviour and induced, under food enrichment conditions, an increased interest in food. Enrichment did not lead to decreased GCM concentration in the group as a whole, but there was a tendency for male and female animals to differ in hormonal reactions to environmental change. A positive correlation between GCM concentrations and pacing behaviour and a negative correlation between GCM concentrations and social behaviour were found. Results suggest that food scattering as an enrichment procedure may be used with maned wolves to enhance welfare, whilst also revealing the importance of taking individual and gender differences into account when planning enrichment techniques.

Societal concern for animals under human care has influenced our approaches to advance animal welfare in a variety of contexts. The Animal Programs Department at the Columbus Zoo and Aquarium sought partnership with the Center for Human-Animal Interactions Research & Education (CHAIRE) at The Ohio State University to develop a holistic welfare approach for the animals within their department using a focal species, the cheetah (Acinonyx jubatus). A one-year project using the Five Domains Animal Welfare Model collected data over six 60-day periods to evaluate long-term cortisol production and behavioural observations of cheetahs under changing environmental factors. Species and individual histories were incorporated with behavioural observations and hair cortisol production, giving a holistic view of welfare. Cortisol and behavioural data were analysed using linear models to compare cheetahs at population and individual levels. Participation in a cheetah run activity, housing occupancy, and 60-day period were found to influence all behaviours within the population and stereotypic behaviour also differed within individual cheetahs. No differences in hair cortisol concentrations were found for the group, but further analysis revealed differences within individuals throughout the study. No correlation of stereotypic behaviour and cortisol levels were found. This study created a welfare assessment protocol that can be used within zoological institutes and was the first to measure cortisol concentrations in hair in cheetahs.

The measurement of salivary cortisol allows non-invasive assessment of welfare in captive animals. We utilised this technique to test the effect of zoo opening on six Asian elephants and two Indian rhinoceros at the Terra Natura Zoological Park, Alicante, Spain, during pre-opening, opening and post-opening periods. Salivary cortisol concentrations were found to be significantly higher during the opening period than during pre- and post-opening periods for both species. This method could prove a useful tool in monitoring the success of decisions taken to improve the welfare of captive animals.

The decision to perform euthanasia in geriatric zoo mammals is usually a highly complex procedure involving ethical, medical, emotional and sometimes political factors. However, subsequent necropsies show that the pathological changes of organs and/or the musculoskeletal system are often already advanced. Therefore, we hypothesise that euthanasia is often delayed to the detriment of the animal's welfare. The purpose of this study was to facilitate and establish an initial, objective, decision-making framework for the euthanasia of geriatric zoo mammals. A scoring-system to assess the physical condition and quality of life in ageing zoo mammals is presented, based on retrospective and prospective investigation of 70 geriatric zoo mammals in five European zoos. Medical records and necropsy reports were studied in retrospective cases. Symptoms were monitored and recorded in prospective cases. Radiographic investigations under general anesthesia or at necropsy were performed additionally. A significant association between symptoms and pathological findings revealed that 36.9% (n = 24/65) of examined animals (n = 41/65) had pathological alterations to the musculoskeletal system and 26.2% (n = 17/65) suffered from neoplasia. Based on the individual reports, 28 veterinarians from different fields of veterinary medicine concluded that these animals had mild to severe pain, discomfort and a significantly reduced quality of life, thus strongly reducing welfare. The proposed scoring system includes all of these factors and offers a simple and reliable tool to support decision-making for euthanasia in geriatric zoo mammals.

The outbreak of coronavirus disease (COVID-19) represents a major public health challenge and a serious threat to sustainable social development. A consideration of animal welfare is clearly justified, given the potential contribution of animals to the spread of the disease. The present study, therefore, sought to investigate the concern the Chinese people have for animal welfare (PCAW) and how their ‘ethical ideology’ (idealism and relativism) determines PCAW after COVID-19, through comparison with the same study, carried out in China in 2015. Our results demonstrated a significant improvement in Chinese PCAW after COVID-19. The adverse impact of COVID-19 may have resulted in a lowered idealism score and this decreased score served to neutralise significant correlations between idealism and PCAW, compared to the 2015 results. The global pandemic did not increase people's relativism score and a significant correlation was found between relativism and PCAW. Gender, age, educational level, public perception of animals after COVID-19, zoo and aquarium visiting were all shown to be predictor variables for PCAW. This study is one of the first to investigate Chinese PCAW after COVID-19 and can therefore provide knowledge that will potentially increase Chinese PCAW.

The ability to monitor the welfare of animal collections in zoological institutions is critical to the mission of these facilities. Historically, zoos have utilised negative indicators of welfare, such as stereotypic behaviour to examine and monitor collection animals. However, absence of stereotypic behaviour or negative indicators of welfare does not indicate that an animal is thriving. The goal of the current study was to continue efforts to validate behavioural diversity as an indicator of welfare using cheetah (Acinonyx jubatus) as a model species. Behavioural and faecal glucocorticoid metabolite data were collected on 18 cheetah at the San Diego Zoo Safari Park over a period of three months to explore the relationship between behavioural diversity and adrenal hormones related to the stress response. Results suggest that behavioural diversity can be utilised as an indicator of animal welfare to monitor animal collections within zoological facilities. However, additional research with other species should be conducted to better understand behavioural diversity as a positive indicator of animal welfare. We hope this manuscript will increase discussion surrounding behavioural diversity as well as increase efforts to validate it as an indicator of welfare.

This study explored the effect of auditory stimulation on the behaviour and welfare of four zoo-housed, female Asian elephants (Elephas maximus). All animals were exposed, in an ABA design, to two conditions of auditory stimulation: a ‘control’ (no auditory stimulation), and an ‘experimental’ condition, during which the animals were presented with a commercially-available CD of classical music. Each condition lasted for five days, with an interim period of two days between each condition (Study 1). The elephants’ behaviour was recorded every minute for four hours a day for the full five days of each condition using instantaneous scan-sampling. The procedure was repeated four months later (Study 2), for a shorter period of time (one day per condition, again using an ABA design) to assess whether the results are generalisable. Analysis of both studies revealed that the elephants spent significantly less of their time stereotyping during the experimental conditions than the control. None of the other behaviours recorded were influenced significantly by auditory stimulation. Overall, the findings from this study suggest that auditory stimulation, in the form of classical music, may be a useful method of reducing stereotypic behaviour in zoo-housed Asian elephants, although more long-term work with a larger number of animals is needed before firm conclusions can be drawn.

The presence of human visitors has been shown to affect the behaviour of several different mammalian species in a number of different zoos, but the behavioural changes observed are not always consistent with a simple ‘stressful influence’ explanation. Data for non-primate species are too sparse to draw meaningful conclusions; but for primates, the evidence reviewed in this paper allows several hypotheses to be tested. Neither a social facilitation nor an audience attraction hypothesis can be generally supported by the available studies. However, these studies are consistent with a general stressful influence hypothesis, although the extent of this influence is itself affected by other variables, notably species and housing differences. There is some evidence that chronic exposure to human audiences may lessen this stressful influence in some species; and in certain circumstances (notably where some members of the public throw food) the effect of the audience is almost an enriching one.

The objective of this study was to determine if housing conditions, specifically pen size and soil enrichment, had an effect on faecal glucocorticoid concentrations in the endangered pygmy rabbit (Brachylagus idahoensis). The success of the captive breeding programme has been limited, so one hypothesis is that chronic stress due to sub-optimal housing conditions may be responsible for poor fecundity. Faecal glucocorticoid concentrations were assessed in 50 females housed among several pen types at two breeding facilities. The highest glucocorticoid concentrations were found in females housed in 0.37 m2 crates as compared to enclosures ranging from 0.96 to 75 m2 in size. Results also indicated that enrichment of enclosures with soil had a significant influence on adrenal activity, based on a reduction in glucocorticoid excretion for females moved from non-soil pens to those with soil. Last, a significant facility effect on glucocorticoid concentrations was observed, suggesting that factors other than housing influenced adrenal activity in these rabbits. In conclusion, based on measurements of faecal glucocorticoids, pygmy rabbits are best managed in enclosures that contain soil for digging burrows. Pen size had little effect on stress hormones, except for crates where limited space and/or absence of soil was associated with higher glucocorticoid concentrations. These results underline the importance of monitoring glucocorticoid concentrations in captive breeding programmes to identify optimal husbandry and management practices.

The present study examined the extent to which the introduction of three female Asian elephants (aged 3, 11, and 27 years) into a group of 1.4 (1 male, 4 female) elephants at Münster zoo, Germany, affects the behaviour and urinary Cortisol levels of the animals involved. At Münster, only the females were monitored — the bull was mainly kept separate. Behavioural observations were carried out before transfer and during the six-month period following transfer, and urine samples were collected regularly from each elephant during the whole observation period. All elephants showed behavioural changes to the process of introduction. The transferred animals increased their social behaviour after arrival in the foreign zoo. Two of them showed an increase in stereotypies and one a reduction in stereotypies. The elephants at Münster reacted with decreased frequencies of stereotypies and increased frequencies of social behaviour and manipulation/exploration behaviour. Six months after transfer, three of the four elephants at Münster and one of the three transferred elephants showed nearly the same behavioural activity pattern as before transfer. One female still showed elevated stereotypic behaviour. From the four elephants in which Cortisol measurements could be reliably performed (two of the transferred elephants and two elephants at Münster), only one individual at Münster responded to the process of introduction with a short-term elevation in urinary Cortisol levels. One elephant showed a negative correlation between locomotion and Cortisol levels and one a positive correlation between stereotypies and Cortisol levels. Taken together, the results suggest that transfer and introduction caused some stress responses in the elephants, but that stress was neither prolonged nor severe. Serious welfare problems may have been prevented through individual behavioural coping mechanisms and former experience with stressful situations.

Good animal welfare is crucial for the success of circuses and zoos. Epidemiological studies of animal welfare that investigate associations between animal-based measures (ABMs) and resource- and management-based measures are needed. However, due to the relatively low numbers of animals within each species kept at individual facilities, such investigations can be difficult to carry out. In this paper, we report the analysis of a multi-facility epidemiological study using data from all regulatory inspections of circus and zoo animals in Sweden for 2010 to 2014. Information from 42 inspections of 38 circuses, and 318 inspections of 179 zoos was analysed. For ABMs assessed during routine inspections of circuses (n = 14) and zoos (n = 61), 9.1 and 14.3% did not comply with requirements for general care of hooves/claws and coat, 10.0 and 8.6% for body condition, and 0 and 1.7% for animal cleanliness, respectively. In addition, the zoo checklist assessed whether animals were kept in appropriate groups, finding non-compliance in 17.0% of inspections. The most frequent non-compliant resource- and management-based measures at routine inspections of circuses were for space (41.7%) and exercise requirements (38.5%). For zoos, 29.4% did not comply with space followed by 28.8% for enrichment requirements. In multivariable logistic regression analyses, zoos that had inadequate or unsafe housing and space design, inadequate bedding, or failed to meet nutritional requirements, were more likely to be non-compliant with at least one ABM. The checklists should be improved to better assess welfare status by including more ABMs; benchmarking of risks and trends over time is also recommended.

Environmental enrichment is a key component in improving the psychological and physiological well-being of animals under professional care. Environmental enrichment involves the addition of stimuli, including objects and cognitive challenges, into the environment in order to increase species-specific behaviour and provide opportunities for choice and control. The effectiveness of enrichment should be evaluated on a case-by-case basis to determine if the desired result has been achieved. Environmental enrichment devices (EEDs) can be utilised to present novel problems to animals under professional care. Here, a submerged interactive cognitive apparatus was presented to eight bottlenose dolphins (Tursiops truncatus) five days a week for 18 weeks and behavioural indicators of animal welfare assessed. As a group, dolphins spent more time in social swims compared to solitary swims and more time at the bottom of the habitat than the middle or top throughout the day, even when the apparatus was not immediately available. Individuals’ differences were apparent in the type and amount of engagement with the apparatus. Three dolphins engaged with the apparatus by solving it or consuming the reward. Two dolphins, D4 and D8, engaged simultaneously with the apparatus and participated in more social swimming with each other. D4 solved the interactive apparatus and engaged in more social active and solitary active behaviours. D1 and D4 increased their use of the bottom of the habitat. This study is the first report of underwater enrichment increasing dolphins time at depth throughout the day even when the enrichment device is not available. The interactive apparatus was an effective form of enrichment for dolphins participating in successful trials.

Behavioural diversity may serve as a positive indicator of animal welfare that can be applied in long-term monitoring schemes in managed settings (eg zoos, laboratories, farms). Behavioural diversity is often higher when animals live in stimulating environments and experience positive events. Unfortunately, welfare researchers have not adopted consistent, standardised approaches to measuring behavioural diversity. The goal of this exploratory study was to utilise data from 41 adult chimpanzees (Pan troglodytes) housed across 16 zoological institutions to examine various models of Shannon's Diversity Index. Specifically, we investigated the impact of: combining versus splitting behaviours, including only positive behaviours, including human interaction, and considering recipient behaviours. We evaluate how the inclusion or exclusion of different behaviours impacts the relationship of behavioural diversity with: (i) concentrations of faecal glucocorticoid metabolites (GCM), a common indicator of adrenal activity; (ii) concentrations of immunoglobulin-A (IgA), an indicator of immune function and potential indicator of positive welfare; and (iii) stereotypic behaviour, a validated indicator of poor welfare. Most indices had significant negative relationships with faecal GCM. Animals that express a variety of behaviours from their species-typical repertoire have lower average faecal GCM concentrations and are likely experiencing better welfare. We did not find significant relationships between the behavioural diversity indices and IgA concentrations. Two indices were inversely associated with stereotypic behaviour. Our findings provide additional support for using Shannon's Diversity Index to calculate behavioural diversity as a robust, valid measure of positive welfare. However, future publications must justify the process for including or excluding behaviours from calculations.

It has been suggested that housing of laboratory primates in two-tiered racks adversely affects the psychological well-being of those primates housed on the lower row. Excessive darkness and its consequences are among the factors suggested to account for the supposed diminished well-being of lower-row inhabitants. Additionally, two-tiered housing has been suggested to introduce unacceptable variation into experimental designs, potentially necessitating additional subjects and/or invalidating results. Only recently have data been published to address these issues, but all studies have involved small numbers of subjects. In the present study, we compared the behaviour of 45 yearling rhesus macaques (Macaca mulatta) housed in upper-row cages with the behaviour of 48 yearling rhesus macaques housed in lower-row cages during a year of single housing. There were no significant differences across cage locations for time spent performing behaviours indicative of diminished psychological well-being (abnormal behaviour, inactivity, vocalisation, self-directed grooming) or for species-typical activities (feeding, playing). The difference in time spent exploring between macaques housed on the lower row and those housed on the upper row approached significance, with lower-row-housed animals spending more time exploring. Although lower-row cages are significantly darker than upper-row cages at our facility, the data from the present study demonstrate that the diminished lighting and other supposed disadvantages experienced by lower-row-housed monkeys have few behavioural consequences. Thus, there are now additional empirical data that suggest that lower-row-housed monkeys are not suffering in a “monkey cave”, and that the findings of research projects using two-tiered housing systems are unlikely to be compromised.

An increasing number of zoos keep their animals in natural-looking enclosures, but it is often unclear whether or not the species’ behavioural and ecological needs are being adequately met. For species that suffer predation in the wild, structural enrichment in captivity can play a crucial role in connection with enclosure use. Firstly, we examined the effectiveness of structural enrichment in modifying enclosure use in an opportunistic carnivore, the red fox (Vulpes vulpes). In a test enclosure, we placed both long wooden and cover structures that simulated natural habitat in predetermined sectors. A group of four foxes were exposed to four treatments: (i) structural enrichment in location 1 (LOC1s); (ii) structural enrichment in location 2 (LOC2); (iii) structural enrichment removed (REM); and (iv) structural enrichment again in location 1 (LOC1e). Sectors containing long wooden structures were preferred significantly compared to the rest of the enclosure. Sector use was selectively shifted to those in which cover structures were present. Structural enrichment had no significant effect on activity. Secondly, in a new outdoor enclosure, we compared the use of sectors with cover or elongated structures with that of corresponding sectors without structures. All individuals showed a significant preference for sectors containing structures. In the course of the three-week observation period, there was a significant decline in preference for structures and a significant increase in activity (week 1 < week 2 = week 3). These results suggest that in medium-sized carnivores, structural enrichment is beneficial when natural features with a net-like distribution over the habitat are simulated.

While the international zoological community is committed to enhancing the welfare of individual animals, researchers have yet to take full advantage of the tools available for non-invasively tracking behavioural and physiological indicators of welfare. We review technology currently being applied in studies of zoo, farm and laboratory animals to regularly monitor welfare status, as well as to evaluate responses to particular stimuli and situations. In terms of behavioural measures, we focus on automated assessments that offer insight into how animals — even those that are nocturnal or elusive — behave when humans are not present. Specifically, we provide an overview of how animal-attached technology (accelerometers, global positioning systems, radio frequency identification systems) can be implemented to generate activity budgets, examine use of space, conduct gait assessments, determine rates of movement and study social dynamics. We also emphasise the value of bioacoustics, as the rate and acoustic structure of certain vocalisations may vary across contexts and reflect an animal's internal state. While it can be challenging to identify non-invasive methods for investigating physiological welfare indicators, we discuss approaches (thermography, tracking measures of heart rate) that may be especially useful for monitoring affective states and psychophysiological functioning. Finally, we make a concerted effort to highlight tools that allow welfare scientists to consider measures of positive welfare. Ultimately, zoos can ensure that each animal has the opportunity to thrive by employing technology to create baseline behavioural and physiological profiles, conduct ongoing monitoring schemes and assess responses to specific conditions, events and stimuli.

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.

Conventional bleeding of small laboratory animals is often associated with stress and injuries that can cause haematomas, inflammation and ultimately the death of animals under investigation. Here, we used faecal glucocorticoid metabolites as an indicator of stress imposed on laboratory mice (Mus musculus domesticus) when bled in three different ways: puncture of the tail vein following mechanical immobilisation; puncture of the retro-orbital plexus following chemical immobilisation; and a minimally invasive technique using blood-sucking bugs (Reduviidae, Heteroptera) without any immobilisation. We hypothesised that blood-sucking bugs provoke a lower hormonal stress response than conventional bleeding techniques because laboratory animals are not handled and because the mechanical stimulus of an insect sting is supposedly weak. Each of the 16 mice was bled using one of the three methods at a time in a random order with seven days of recovery between subsequent bleeding events. To monitor the stress hormones, we determined corticosterone metabolites in faecal samples of mice collected one day before, 8 h after and one day after the bleeding event. Concentrations of faecal glucocorticoid metabolites increased in all three treatment groups compared with baseline values. However, average concentration of stress hormone metabolites after bleeding was higher by a factor of about 1.5 when conventional bleeding techniques were applied than when bugs were used. We conclude that blood-sucking bugs may offer a gentle alternative for obtaining blood samples from small animals such as mice.

The rise in public interest in animal rights and welfare during the last two decades has been dramatic, and concern for zoo animals is evident throughout society in many South East Asian countries. It is essential that problems related to animal welfare are understood in order for zoos to make significant improvements in their professional and ethical standards. In this paper, I describe in detail the procedures of welfare and ethics evaluations in South East Asian zoos. Zoo evaluation is an ongoing process and is carried out on behalf of the South East Asian Zoos Association to evaluate the members of this organisation. During recent evaluations, several major and minor problems have been identified and constructive suggestions have been provided to zoo authorities which have in turn significantly improved the standards of animal welfare and ethics. Thus, the welfare evaluation procedures outlined in this paper could serve as a model for other zoos to follow — locally, regionally and globally.