Central nervous system mycobacteriosis caused by in degus ().

Degus () that were kept at a breeding facility presented with neurological or respiratory symptoms and died. Necropsies were performed on 9 individuals, and no significant gross lesions were found. Histologically, spinal cord necrosis was observed in all 9 cases and granulomatous myelitis in 5 of the 9 cases. Locally extensive necrosis of the brain and encephalitis were observed in 7 of the 9 cases. Acid-fast bacteria were found in the spinal cords, brains, and lungs from all 9 cases. Immunohistochemically, antigen was observed in the spinal cords, brains, and lungs from all 9 cases. Double-labeling immunofluorescence revealed antigen in IBA1- and myeloperoxidase-immunopositive cells. Extracted genomic DNA from 8 of the 9 cases was successfully amplified with the primers for and genes, and the polymerase chain reaction products were identified as by DNA sequencing. This report highlights the susceptibility of degus to infection in the central nervous system.