Multi-drug resistant Salmonella ser. Dublin cultured from cryopreserved Holstein semen

A 17-month-old Holstein bull presented from a stud in the Midwest United States to the University of Wisconsin-Madison Veterinary Teaching Hospital and Wisconsin Veterinary Diagnostic Laboratory for euthanasia and necropsy following isolation of a multi-drug resistant strain of Salmonella enterica subspecies enterica serotype Dublin from cryopreserved semen cultured as part of the stud's protocol for random sampling for bacterial culture. Additionally, the bull had five consecutive monthly positive Salmonella ser. Dublin enzyme-linked immunosorbent assay tests with percent positivity ranging from 135 to 157. Antemortem diagnostics included physical examination, complete blood count, biochemistry and blood culture. A postmortem examination was performed with culture, PCR and histopathology of numerous tissues and fluids. Salmonella ser. Dublin was cultured from urine, bile, faeces, prostate, seminal vesicles, preputial mucosa, colon and small intestine. To the authors' knowledge, this is the first report of Salmonella ser. Dublin being isolated from the male reproductive tract and cryopreserved bovine semen in the United States.