Mycobacteriosis are important zoonoses and clinicians should be aware of their potential risks. A rescued 3-year-old rabbit was presented for acute rhinitis. After 10 days of antibiotic therapy, no improvement was noted and intermittent diarrhoea, dysorexia and weight loss arose. The patient was hospitalized and haematological and faecal examinations were performed. A later ultrasound examination showed intestinal subocclusion. After stabilization, an explorative laparotomy was performed and several caseous nodules were found on the small intestine walls. The rabbit was euthanized and necropsy showed other nodules in the lungs, along with swelling of mesenteric lymph nodes. Cytological and histological examination revealed the presence of acid-fast-resistant bacteria, which were identified as Mycobacterium avium. Mycobacterial infections are uncommon in pet rabbits but their potential impact on human health and the unspecific clinical signs should suggest to include them in the differential diagnoses for respiratory and gastrointestinal disorders.Mycobacteriosis are important zoonoses and clinicians should be aware of their potential risks. A rescued 3-year-old rabbit was presented for acute rhinitis. After 10 days of antibiotic therapy, no improvement was noted and intermittent diarrhoea, dysorexia and weight loss arose. The patient was hospitalized and haematological and faecal examinations were performed. A later ultrasound examination showed intestinal subocclusion. After stabilization, an explorative laparotomy was performed and several caseous nodules were found on the small intestine walls. The rabbit was euthanized and necropsy showed other nodules in the lungs, along with swelling of mesenteric lymph nodes. Cytological and histological examination revealed the presence of acid-fast-resistant bacteria, which were identified as Mycobacterium avium. Mycobacterial infections are uncommon in pet rabbits but their potential impact on human health and the unspecific
clinical signs should suggest to include them in the differential diagnoses for respiratory and gastrointestinal disorders.