Physical and Physiological Indicators of Welfare in Guinea Pigs (Cavia porcellus) Serving as Ambassador Animals

Relationship between Ear Temperature, Behaviour and Stress Hormones in Guinea Pigs (Cavia porcellus) during Different Interactive Activities in Zoos

Guinea pigs (Cavia porcellus) are used for interactive activities in zoos; therefore, it is important to investigate their welfare. This study aimed to evaluate the validity of measuring the guinea pigs' body temperature of guinea pigs through the ear canal and investigate the relationship among changes in the expression of negative behavior, changes in body temperature, and changes in salivary cortisol concentration, and examine the effects of different interactive activities. In the normal interactive activities performed at the site, the decreased body temperature of pigs was observed over time. In contrast, increased body temperature was observed in excessive interactive activities, which are not recommended. Among the negative behaviors, "Head turning" and "Locomotion" increased significantly in excessive interactions compared to normal interactions, but "Head tossing" decreased significantly over time in both types of interactions. "Freezing" was observed only in excessive interactions. Salivary cortisol concentration increased significantly for all activities. Investigating the relationship between the individual expression of negative behavior and changes in body temperature and changes cortisol level made it possible to uncover the potential for inferring an animal's physiological state. Combining ear temperature monitoring and behavioral observation during zoo interaction activities is recommended as an ethical and scientifically supported practice.

A Reexamination of the Relationship between Training Practices and Welfare in the Management of Ambassador Animals

There is an ethical need to document and develop best practices for meeting ambassador animals' welfare needs within the context of meeting zoo and aquarium program objectives. This is because ambassador animals experience direct and frequent contact with humans. This paper rigorously synthesizes behavioral research and theory, contemporary practices, and personal experiences to offer key concepts that can be applied to meet ambassador animal welfare needs. These key concepts include addressing an animal's recognition of choice and control, the use of the most positive and least intrusive effective interventions when training animals to participate in programming, and an overall reduction in aversive strategy use. Our model for increasing ambassador animal welfare focuses on seven main areas of concern, including the following: choosing the most suitable animal for the program; choosing the human with the right skills and knowledge for the program; using the most positive, least intrusive, effective training methods; developing a strong trusting relationship between trainer and animal; developing a comprehensive enrichment program; the need for institutional support; and creating opportunities for animals to practice species-appropriate behaviors. Our model will provide guidelines for improved ambassador animal welfare that can be refined with future research.

Review of Rat (Rattus norvegicus), Mouse (Mus musculus), Guinea pig (Cavia porcellus), and Rabbit (Oryctolagus cuniculus) Indicators for Welfare Assessment

The monitoring and assessment of animals is important for their health and welfare. The appropriate selection of multiple, validated, and feasible welfare assessment indicators is required to effectively identify compromises or improvements to animal welfare. Animal welfare indicators can be animal or resource based. Indicators can be collated to form assessment tools (e.g., grimace scales) or animal welfare assessment models (e.g., 5 Domains) and frameworks (e.g., 5 Freedoms). The literature contains a wide variety of indicators, with both types needed for effective animal welfare assessment; however, there is yet to be an ideal constellation of indicators for animal-based welfare assessment in small mammals such as guinea pigs (Cavia Porcellus), mice (Mus musculus), rabbits (Oryctolagus cuniculus), and rats (Rattus norvegicus). A systematic review of grey and peer-reviewed literature was performed to determine the types of animal-based welfare indicators available to identify and assess animal health and welfare in these small mammals maintained across a wide variety of conditions. The available indicators were categorised and scored against a selection of criteria, including potential ease of use and costs. This review and analysis aim to provide the basis for further research into animal welfare indicators for these species. Future applications of this work may include improvements to animal welfare assessments or schemes, guiding better management, and implementing future strategies to enable better animal welfare.

Effects of castration and sterilization on baseline and response levels of cortisol-A case study in male guinea pigs

An uncontrolled reproduction of animals in human hands should be avoided. To meet this goal, animals are widely castrated, i.e., the gonads are completely removed. Since the gonads are the most important source of sex hormones, this is a serious intervention in the entire endocrine system of an organism. Sterilization is a much less invasive procedure. Thus, it could have advantages over castration. Therefore, the overall aim of this study was to analyze the effect of castration vs. sterilization on the release of glucocorticoids, i.e., an important indicator for welfare. Taking domestic guinea pigs as a model system, we studied baseline and response cortisol values (cortisol is the main glucocorticoid in guinea pigs) in castrated, sterilized, sham-operated and intact males and baseline values in their cohoused females. Whereas baseline values of males did not differ between the groups, castrated males showed significantly higher cortisol response levels than intact, sham-operated and sterilized males. Females housed with castrated, sterilized, sham-operated or intact males did not differ in their cortisol concentrations, neither shortly after being placed with the respective male or after being co-housed for several weeks. Overall, the results support the hypothesis that castrated males exhibited a higher cortisol responsiveness during acute challenge which could point to a generalized impaired welfare of castrated males in comparison to intact, sham-operated and sterilized males. Our results provide first evidence for a potential negative impact of castration on the animals' welfare, while at the same time pointing toward sterilization representing a less invasive, promising alternative. Therefore, the results may stimulate future research on this topic to further detect potential welfare-related side effects of castration.

Behavior and adrenal physiology of Magellanic penguins (Spheniscus magellanicus) serving as ambassador animals

Ambassador animals are part of many zoo programs, but studies assessing their impact on these animals are relatively rare. This study validated an excrement glucocorticoid metabolite (GCM) assay for Magellanic penguins and used GCM measures in conjunction with behavioral observations to evaluate individual responses to participation in an ambassador animal program. Excrement samples and behavioral observations were collected daily from each bird during two phases, 1 week during which it participated in a twice-daily ambassador program and 1 week in which it did not. We found no differences in GCMs between phases or in comparisons between penguins with 5 or 10 years of program experience. GCM also did not show significant individual variation and did not increase over time during the program phase. There were no significant correlations between bird experience and behavior frequencies, nor GCM concentrations and behavior, across birds. We observed significant positive correlations between the penguins' engagement with novel objects during programs and their unguided approach to guests. Our results suggest that there is no adverse physiological effect of program participation on these penguins, that behavioral and physiological responses may be decoupled, and that choice and control can increase desired behaviors behavior during ambassador programs.

Glucocorticoid Production, Activity Levels, And Personality Traits Of Fennec Foxes (Vulpes zerda) Managed For Different Roles In Zoos

Fecal glucocorticoid metabolite (FGM) concentrations, activity, and personality were assessed for 35 fennec foxes (Vulpes zerda) to determine whether animals managed as ambassadors differed from exhibit or off-exhibit animals. A FGM assay, pedometer, and personality assessment tool were validated. Then, fecal samples and movement data were collected during winter and summer periods. Handling was recorded, and the personality of each fox was evaluated. Generalized linear mixed models assessed the relationships between FGM concentrations, activity, personality, handling, sex, season, rearing type, and role. FGM concentrations did not differ in relation to role or handling. Foxes were most active at night; the time of peak activity did not vary with role or handling. Foxes were more active in winter; males were more active than females, and ambassador foxes were more active than off-exhibit animals. Hand-reared foxes were more sociable, and, at one institution, ambassador foxes were more sociable than foxes in other roles. These results suggest that management for ambassador programs is not associated with changes in glucocorticoid production or circadian patterns but may increase activity and be associated with greater sociability.

Chinchilla (Chinchilla lanigera) behavioral responses to a visual signal preceding handling

Zoos use ambassador animals in educational programs featuring close contact with humans. Chinchillas (Chinchilla lanigera) at the Saint Louis Zoo are retrieved for programs by a keeper wearing brown handling gloves, but green cleaning gloves are worn during normal husbandry when physical contact with the animal is only incidental. The chinchillas' primary keeper anecdotally reported more reactivity and movement from chinchillas when approached with handling gloves. Animals' behavioral reactions to the presence of humans often include locomotion and vigilance, but these responses may be attenuated by predictability. To investigate these behaviors, handling trials involving brief contact attempts with both cleaning and handling gloves were filmed. Results indicated that chinchillas responded to disturbances by moving, jumping, and adopting more alert body postures. Surprisingly, movement was recorded in longer durations when the keeper attempted to touch the animals with cleaning gloves. This higher arousal may indicate that the animal was not expecting to be handled, yet an attempt to do so was being made. This reaction provides evidence that potentially aversive events should be reliably and consistently signaled.