Animal Welfare: Could Adult Play be a False Friend?

There is no consensus regarding the functions of play. As play behavior is a characteristic of young stages of development, it has been suggested that the higher prevalence of adult play observed in domestic animals could be the result of their “neotenic retardation.” Functional hypotheses have dealt with the long term benefits, such as “rehearsal,” […]

Serial Cognition and Personality in Macaques

We examined the associations between serial cognition and personality in rhesus macaques (Macaca mulatta). Nine macaques were tested on a simultaneous chaining task to assess their cognitive abilities. They were also rated for personality traits and scored according to a previously extracted six component structure derived from free-ranging rhesus macaques. Friendliness and Openness were positively […]

Terminal investment and senescence in rhesus macaques (Macaca mulatta) on Cayo Santiago

Long-lived iteroparous species often show aging-related changes in reproduction that may be explained by 2 non-mutually exclusive hypotheses. The terminal investment hypothesis predicts increased female reproductive effort toward the end of the life span, as individuals have little to gain by reserving effort for the future. The senescence hypothesis predicts decreased female reproductive output toward […]

Positive reinforcement training as a technique to alter nonhuman primate behavior: Quantitative assessments of effectiveness

Many suggest that operant conditioning techniques can be applied successfully to improve the behavioral management of nonhuman primates in research settings. However, relatively little empirical data exist to support this claim. This article is a review of several studies that discussed applied positive reinforcement training techniques (PRT) on breeding/research colonies of rhesus macaques (Macaca mulatta) […]

Social capital and physiological stress levels in free-ranging adult female rhesus macaques

Social animals with greater access to social support, i.e. higher levels of social capital, may be able to cope better with the challenges they face in their day-to-day lives, and this may be reflected in lower physiological stress levels. Here, we examine the relationship between social capital and fecal glucocorticoid (GC) levels in pregnant free-ranging […]

Training a Large Troop of Rhesus Macaques To Co-Operate During Catching: Analysis of the Time Investment

This study demonstrates that only a minimal time investment was needed to train a large troop of laboratory non-human primates to co-operate in the catching procedure. A group of 45 rhesus macaques (Macaca mulatta) was trained to enter a chute system voluntarily and be caught one by one. The total duration of the training sessions […]

Diving and underwater swimming as enrichment activities for captive rhesus macaques (Macaca mulatta)

In order to assess the environmental enrichment value of a small swimming pool for captive juvenile rhesus macaques (Macaca mulatta), observations of social and individual behaviours were made during baseline and experimental (pool) conditions. When the pool was available there was less social grooming and cage manipulation, and more play. Most of the monkeys engaged […]

Assessment of stress in non-human primates- application of the neutrophil activation test

A technique measuring leukocyte (neutrophil) activity was used to examine differences between stress levels in a breeding colony of rhesus macoques housed in either a traditional caging system or open-rooms. The leukocyte activation test measured the degree to which blood from the two treatment groups could launch a further neutrophil response (superoxide production) to an […]

Using the Mesh Ceiling as a Food Puzzle to Encourage Foraging Behaviour in Caged Rhesus Macaques (Macaca Mulatta)

An attempt was made to encourage more foraging behaviour in eight pair-housed adult rhesus macaques (Macaca mulatta). No special device and no special food were used. Daily commercial dry food rations (238g per animal) consisting of 33 bar-shaped or 16 star-shaped biscuits per animal were placed on the mesh ceiling of the cages instead of […]

Effects of Enrichment on Veterinary Treatment of Laboratory Rhesus Macaques (Macaca Mula1ta)

For captive primates, environmental enrichment may improve psychological well-being, as indicated by changes in the frequency of species-typical and abnormal behaviours. The effects of enrichment on physical well-being have also been examined, but little attention has been devoted to the relationship between enrichment and animal health. We therefore studied the health records of 98 rhesus […]