Parentally deprived juvenile Owl monkeys suffer from long-term high infection rates but not from altered hair cortisol concentrations nor from stereotypic behaviours

Background: In captive colonies, owl monkeys’ mothers sometimes reject their newborns. To prevent, mortality infants are manually raised by veterinarians. Both parental separation and rejection are stressful experiences, associated with elevated stress, physical, and behavioural disorders. The effect of parental deprivation in IVITA’s owl monkeys stress profiles and health is unknown. Methods: We compared stress biomarkers such as hair cortisol (using cortisol ELISA), stereotypic behaviours (with infrared cameras), and infection histories in juveniles separated from parents soon after birth (n = 14, ~17 months) and controls (n = 11, ~17 months). Results: Parentally deprived owl monkeys show higher infection rates than controls (p =.001). However, they display no higher incidence of biomarkers of stress: Neither stereotypic behaviour nor cortisol in hair was different between cohorts. Irrespective of deprivation status, rates of infection, and concentration of cortisol in hair were positively associated (R² =.29, p =.005). Conclusion: Early parental deprivation and natural high levels of cortisol secretion are associated with elevated infection levels in the IVITA owl monkey juveniles detectable up to 17 months post separation.