On Thursday, September 14, 2017, the California Animal Health & Food Safety Laboratory (CAHFS) and the California Department of Fish & Wildlife (CDFW), Wildlife Investigations Laboratory (WIL) hosted a bighorn sheep necropsy course at the CAHFS Diagnostic Laboratory in San Bernardino, California. Assisting with the course were Dr. Peregrine Wolff and wildlife technician Chris Morris from the Nevada Department of Wildlife (NDOW). In attendance were CDFW regional biologists, scientific aides, and veterinarians. The course served as an opportunity for attendees to learn how to recognize, describe, and collect samples from bighorn sheep during field necropsies. It also provided a reminder of how important it is to keep domestic sheep populations separated from free-ranging bighorn populations in order to maintain healthy herds.
After introductory remarks from Dr. Ben Gonzales (CDFW WIL), Dr. Francsisco Uzal (CAHFS) led a discussion on how to describe macroscopic lesions (i.e. distribution, size, shape, demarcation, color, consistency, contour) along with a review of the pathology of a few select domestic and bighorn sheep diseases. Dr. Francisco Carvallo (CAHFS) then expanded upon the main respiratory pathogens of bighorn sheep, which includes lungworms (Protostrongillus spp.), bacteria (e.g. leukotoxin-positive Pasteurellaceae, Mycoplasma ovipneumoniae), and viruses (e.g. respiratory syncytial virus, parainfluenza-3 virus). Following an important review of appropriate PPE (personal protective equipment) to utilize during bighorn sheep necropsies led by Meridith Rhea (CAHFS), Dr. Peregrine Wolff (NDOW) led a discussion on field necropsy techniques and nasal tumors of bighorn sheep to wrap up the morning session.
The afternoon was spent observing a bighorn sheep necropsy demonstration performed by Janet Moore (CAHFS) and Akinyi Nyaoke (CAHFS). Attendees were then given the opportunity to perform their own bighorn sheep necropsies under the guidance of the aforementioned instructors, along with assistance from Karina Fresneda (CAHFS), Patricia Gaffney (CAHFS), Dr. Francsisco Uzal (CAHFS), Dr. Francisco Carvallo (CAHFS), Dr. Peregrine Wolff (NDOW), Chris Morris (NDOW), Dr. Brandon Munk (CDFW WIL), Dr. Ben Gonzales (CDFW WIL) and Dr. Andrew Di Salvo (CDFW WIL).