Influences of castration on the performance of landmine-detection rats (Cricetomys gambianus)

Anti-Persoonsmijnen Ontmijnende Product Ontwikkeling has employed pouched rats as mine-detection animals for approximately 10 years in sub-Saharan Africa, where the species is indigenous, and now plans to deploy the rats in areas where they are not indigenous. To prevent the possible introduction of an invasive species in those regions, all rats must be castrated before deployment. The research described in the present article was conducted to determine whether castration affects the performance of pouched rats as mine-detection animals. Five sex-, age-, and performance-matched pairs of pouched rats, 3 male pairs and 2 female pairs, were randomly divided into 2 groups: the experimental group undergoing castration procedures and the control group remaining out of training for the same duration as the experimental group. No statistically significant differences were found between the performance of experimental and control groups after the intervention despite high statistical power to detect such a difference, and equivalence tests suggest that any possible effects are of no practical significance.