Economic benefits of controlling internal and external parasites in South American camelids.

A trial was carried out in alpacas (Lama pacos) and llamas (Lama glama) to determine the economic benefits of controlling both external and internal parasites by the use of ivermectin ("Ivomec," Merck Sharp & Dohme). After four months the treated male alpacas gained on average 3.1 kg more than the untreated males, and their fleece weighed 0.36 kg more. The treated female alpacas gained 1.9 kg more than the controls, but their fleece weighed 0.03 kg less. This treatment gave a net financial benefit to the farmer of U.S. $3.54 for each of his male alpacas and U.S. $1.36 for each of his female alpacas. The results for the llamas were not significant because there was great variation in the weight gains (and losses). Because the value of llama fleece is less, the economic benefits were also less.