Immobilization of game animals in trypanosomiasis research

The proximity of human populations to communities of large animals in Africa creates suitable conditions for the transmission of zoonotic diseases. Since the indiscriminate destruction of these communities to control zoonoses is highly undesirable, the epidemiological role of the animals must be properly assessed in order that alternative methods of control can be developed. For this purpose, techniques should be available to permit large animals to be examined alive. Immobilization techniques using various drugs were tried but only limited success was achieved with the species most likely to be involved in the transmission cycle of trypanosomiasis. In the study reported here, xylazine was the drug selected, one reason being that an antagonist was not required. The drug was administered from a distance by means of a projectile syringe shot from a special rifle. In seven attempts, two waterbuck (Kobus defassa) and one reedbuck (Redunca redunca) were sufficiently immobilized to be handled. The reactions of all seven animals, whether successfully immobilized or not, are discussed.