Case report: disseminated Staphylococcus aureus infections in two infant desert cottontail rabbits (Sylvilagus audubonii)

Staphylococcus aureus is a frequent pathogen in mammals, including rabbits. It can cause suppurative inflammation with a variety of clinical presentations, sometimes resulting in high morbidity and mortality. Outbreaks have been reported in both domestic European rabbits (Oryctolagus cuniculus), and in cottontail rabbits (Sylvilagus spp.). The Colorado Wild Rabbit Foundation recently identified two cases of disseminated S. aureus infections in sibling infant desert cottontail rabbits (S. audubonii) that were presented for rehabilitation. This case report describes the course of the disease, attempted treatment, and pathology findings. Culture and sensitivity tests indicated susceptibility of the pathogen to all antibiotics tested, including trimethoprim-sulfamethoxazole (TMP-SMZ). However, both cases resulted in disseminated spread, against which TMP-SMZ was ineffective. Cottontail rabbit rehabilitators should be aware of the potentially subtle clinical signs, the possibility of outbreaks within a facility, and the difficulties in treating this disease.