Use of cloprostenol as an abortifacient in the llama (Lama glama)

As part of a larger project investigating the development and heritability of choanal atresia glama), it was necessary to develop a protocol for aborting llamas at various stages of gestation. Twenty-seven animals between 4 and 7 mo of gestation were successfully aborted a total of 53 times following two 250 microg intramuscular injections of cloprostenol at 24 h intervals. Abortion was induced once in 10 animals and multiple times (range 2 to 5) in 17 animals. Twenty-four animals (45.2%) aborted 3 d following the first injection, with 20 animals (37.7%) aborting 4 d post prostaglandin administration. Other animals aborted at 2 d (n=6, 11.3%), 5 d (n=2, 3.8%), and 7 d (n=1, 1.9%) following drug administration. Forty-nine (92.5%) of the abortions occurred following a single series of injections, while 4 animals (7.5%) aborted following a second series of injections. No confirmed pregnant animals failed to abort following the second series of cloprostenol injections. Conception rates in animals rebred 2 to 4 wk following an abortion were comparable to those of untreated animals in the research herd. Unlike the severe hypertension and death that has been reported following dinoprost tromethamine administration in the llama, no adverse reactions were observed in this study following cloprostenol administration. The results demonstrate that llamas can be safely and effectively aborted up to 7 mo of gestation (normal full term gestation = 342 +/- 10 days) without adverse effects on subsequent fertility.