The white-tailed deer (Odocoileus virginianus peruvianus) is a hoofed mammal widely distributed on the Peruvian coast and highlands and is one of the most exploited game species in the country, especially in the El Angolo Game Reserve in Piura. In 2011, tens of deer with signs of salivation, lameness and diarrhoea were reported there, and they were finally found dead. A necropsy was performed on a female found dead, taking samples for pathology, radiology and microbiology. The presence of three genera of anaerobic bacteria, Fusobacterium sp, Arcanobacterium sp and Actinomyces sp and lesions compatible with necrobacillosis were found.