Survey of necropsy results in captive red wolves (Canis rufus), 1992-1996

Through the Red Wolf Species Survival Plan, the captive red wolf (Canis rufus) population was developed with the intent of reestablishing wild populations. One part of the plan was a survey for diseases that might occur as a result of population homogeneity or that might impede breeding success and reintroduction. For this survey, complete necropsies and histopathologic analyses were performed on 62 red wolves from 1992 to 1996. Major causes of 22 neonatal deaths were parental trauma, parasitic pneumonia, and septicemia. Common neonatal lesions included pododermatitis and systemic ascariasis. Cardiovascular anomalies and systemic parasitism were found in two juveniles. Causes of death in the 38 adults included conspecific trauma, neoplasia, or gastrointestinal diseases such as necrotizing enteritis, intestinal perforation, and gastric volvulus. Lymphosarcoma represented 50% of the fatal neoplasms. Three adults died from cardiovascular failure or hyperthermia during handling, and several adults were euthanized for suspected genetic diseases. Overall, the captive population had few significant health problems, but population fitness might be improved by continued removal of potentially deleterious genes from the breeding population and by modifying the husbandry of neonates and adults.