Safety of a medicated feed to treat parasites of northern bobwhite (Colinus virginianus).

Parasites are a significant health concern for livestock and domestic animals and much effort has been invested in the development, testing, and implementation of treatments. There has, however, been relatively little done to treat wild animal populations for parasites. Northern bobwhite (Colinus virginianus) is a species of conservation interest, that could benefit from anti-parasite treatment. Currently, there are no anthelmintics approved for wild game birds in the U.S., and target animal safety data needs to be provided to support the registration of an anthelmintic that can be administered to wild bobwhite as part of the approval process. The purpose of this research was to test the safety of fenbendazole at a recommended concentration of 100 parts per million (ppm) for 21 days in feed. One hundred-sixty 8-week-old bobwhite were randomly assigned to a diet of 0, 100, 200, or 300 ppm for 63 days. Birds were monitored twice daily for overt signs of intoxication, and body weight, feed consumption, and feed conversion, were determined for each pen. At the end of the study, three birds from each pen were randomly selected to be assessed for feather abnormalities, hematology, blood chemistry, necropsy, and histopathology. There were no treatment related mortalities. There were also no treatment related effects on body weight, feed consumption, feed conversion, feathering, hematology, blood chemistry, gross pathology, or histopathology. This study indicates that fenbendazole at 100 ppm for 21 days in feed is safe for bobwhite and represents the first drug approved for use in a free-ranging wildlife species that is commercially available and registered by the United States Food and Drug Administration.