Assessing Allostatic Load in Ring-Tailed Lemurs (Lemur catta).

Area of Science:

• Veterinary Science
• Primatology
• Animal Behavior

Background:

• Stress responses are vital adaptive mechanisms in animals.
• Chronic stress in humans is linked to adverse health outcomes and mortality.
• Allostatic load (AL) quantifies physiological dysregulation from chronic stress, but its application in non-human primates is limited.

Purpose of the Study:

• To investigate the relationship between allostatic load index (ALI) and various individual, social, medical, and husbandry factors in ring-tailed lemurs (Lemur catta) under human care.
• To assess the utility of ALI as a measure of chronic stress in lemurs.

Main Methods:

• An allostatic load index (ALI) was calculated for 38 lemurs using six serum biomarkers: albumin, cortisol, dehydroepiandrosterone-sulfate, DNA damage, glucose, and prostaglandin E2.
• Lifetime medical and husbandry records were used to document potentially stressful factors, including time spent indoors, group size, and group composition changes.

Main Results:

• Higher ALI was associated with increased time spent indoors, smaller average group sizes, and fewer minor group composition changes.
• No significant relationship was found between ALI and the sex or age of the lemurs.
• Specific social and husbandry factors demonstrated a correlation with allostatic load in the studied lemur population.

Conclusions:

• The allostatic load index (ALI) shows promise as a tool for assessing chronic stress in lemurs and potentially other animals under human care.
• Environmental and social management strategies may be crucial in mitigating chronic stress and improving the welfare of lemurs in captivity.