Vasectomy in Drill Monkeys (Mandrillus leucophaeus) - A Population Management Tool

Management intervention to avoid inbreeding in captive breeding programs is essential to maintain maximum genetic diversity. Vasectomy was enlisted in drill monkeys (Mandrillus leucophaeus) to achieve this purpose without altering the social dynamics of the groups. All the vasectomies were carried out at the Drill Rehabilitation and Breeding Centre, Cross River State, Nigeria. Vasectomy in drill monkeys and the postoperative results were documented. Twelve drill monkeys were vasectomised between 2001 and 2008; six of the males were vasectomised as alpha males, 3 were ex-alphas at vasectomy, while 3 were males from genetically well-represented lineages. Ten of the animals were wild born while 2 were captive bred. No changes in group dynamics or post-surgical complications were recorded. There was a reduction in drill births in groups where the alpha males were vasectomised.