Positive reinforcement training moderates only high levels of abnormal behavior in singly housed rhesus macaques

This study evaluated the application of positive reinforcement training (PRT) as an intervention for abnormal behaviors in singly housed laboratory rhesus macaques at 2 large primate facilities. Training involved basic control behaviors and body-part presentation. The study compared baseline behavioral data on 30 adult males and 33 adult females compared with 3 treatment phases presented […]

Bioacoustic Monitoring of Aggression in Group-Housed Rhesus Macaques

Many captive primate facilities house rhesus macaques in multimale-multifemale social groups in large enclosures that simulate the natural social and environmental features characteristic of the species, enhancing their reproductive performance as well as their psychological well-being, yet one of the most difficult management problems in socially housed macaques is their propensity for exhibiting spontaneous bouts […]

Working With Rather Than Against Macaques During Blood Collection

Training macaques to cooperate during blood collection is a practicable and safe alternative to the traditional procedure implying forced restraint. It takes a cumulative total of about 1 hr to train an adult female or adult male rhesus macaque successfully to present a leg voluntarily and accept venipuncture in the homecage. Cooperative animals do not […]

Risk Factors and Remediation of Self-Injurious and Self-Abuse Behavior in Rhesus Macaques

Considered signs of decreased welfare—abnormal behaviors such as self-injury and self-abuse among nonhuman primates housed in the laboratory—may put into question the validity and reliability of scientific research using these animals as models. Providing environmental enrichment decreases the incidence of some undesirable behaviors but is often unsuccessful at ameliorating the most severe types of abnormal […]

Early social experience affects behavioral and physiological responsiveness to stressful conditions in infant rhesus macaques (Macaca mulatta)

Abstract Studies on early development have demonstrated the profound effects of early social experience on the behavioral development and physiology of young rhesus macaques. Given these relationships, we hypothesized that rhesus macaques exposed to different nursery-rearing conditions may develop unique biobehavioral profiles. If this is true, the assessment of temperament may allow us to pinpoint […]

Rhesus macaques (Macaca mulatta) as living fossils of hominoid personality and subjective well-being

Personality dimensions capturing individual differences in behavior, cognition, and affect have been described in several species, including humans, chimpanzees, and orangutans. However, comparisons between species are limited by the use of different questionnaires. We asked raters to assess free-ranging rhesus macaques at two time points on personality and subjective well-being questionnaires used earlier to rate […]

Dimensions of response to novelty are associated with social engagement and aggression in adult male rhesus macaques (Macaca mulatta)

In this study, the authors tested the hypothesis that behavioral response across social and nonsocial, novel and familiar conditions may be guided by the same trait(s) related to impulsivity in adult male rhesus macaques. The authors assessed 23 individuals’ behavioral response to a series of nonsocial novel scenarios, as well as aggression and sociality within […]

Lower-Row Caging in a Two-Tiered Housing System does not affect the Behaviour of Young, Singly Housed Rhesus Macaques

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 […]

A Comparison of the Effects of Simple Versus Complex Environmental Enrichment on the Behaviour of Group-Housed, Subadult Rhesus Macaques

Enrichment of the environments of captive primates is currently of interest as both a basic and an applied research question, particularly when social and inanimate enhancements are used simultaneously. We measured the behavioural effects of two intensities of inanimate enrichment on 12 unimale-multifemale groups and 12 all-male groups from three cohorts of three to four-year-old […]

Cognitive bias in a non-human primate: husbandry procedures influence cognitive indicators of psychological well-being in captive rhesus macaques

The measurement of ‘cognitive bias’ has recently emerged as a powerful tool for assessing animal welfare. Cognitive bias was initially, and widely, studied in humans, and describes the way in which particular emotions are associated with biases in information processing. People suffering from clinical levels of anxiety or depression, for example, interpret ambiguous events more […]