Rhesus macaque (Macaca mulatta) group formation and housing: Wounding and reproduction in a specific pathogen free (SPF) colony

In the present report, we examined the effects of group formation strategy and corral design on wounding and reproduction rates in rhesus macaques. Sp ecifically, we examined group formation using a staged strategy, in which s mall groups of animals were introduced incrementally over a period of weeks , and a rapid formation strategy, in which all animals were introduced in 1 day. We also examined group formation using a divided corral design that f acilitated visual and social separation of individuals, and an undivided co rral design that did not facilitate visual or social separation. Dependent measures were wounding and reproductive rates over each of the 2 years that followed group formation. Results indicate that incrementally releasing su bgroups of animals, and using a corral design that provides for visual and social separation of individuals, are effective strategies far reducing rat es of traumatic wounding when forming multimale-multifemale rhesus macaque breeding groups. However,it must be noted that differences in formation str ategy and corral design did not lead to higher reproductive rates. We concl ude that incrementally releasing animals in hierarchical subgroups, and usi ng a divided vs. undivided housing design, reduced intra-group wounding and associated demands on veterinary and animal management resources following formation of rhesus macaque breeding groups. Am. J. Primatol. 49:339-347, 1999. (C) 1999 Wiley-Liss, Inc.