Psoroptic scabies in bignorn sheep (Ovis canadensis mexicana) in New Mexico

Prior to 1978, no reports were made of scabies lesions or mites recovered from any Mexican bighorn sheep (Ovis canadensis mexicana) examined in the San Andres National Wildlife Refuge in southern New Mexico. In 1978, all of five rams harvested by hunters had live mites of the genus Psoroptes and active lesions of scabies in their ears and/or on their bodies. Deaths due to scabies were not documented during this outbreak although aerial helicopter surveys conducted in March, June and September, 1979 recorded less than half the sheep observations of five previous and similarly conducted surveys. After measurement of the length of the outer opisthosomal setae of the male mites, they appear to be Psoroptes ovis (Hering), the common scabies mite of domestic sheep, cattle and horses. Final specific determination must await proposed transmission studies with domestic livestock.