Testicular Abscess in a Aberdeen Angus Bull

An 18-month old Aberdeen Angus bull presented with semen quality unsuitable for cryopreservation for six months. The left testis was enlarged. The right testis was unremarkable. There was astenozoospermia and teratozoopermia. Ultrasound of the left testicular parenchyma revealed a round 2.5-cm, focal hypoechoic lesion with a hyperechoic center and well-defined margins. Abscess or tumor was suspected. Fine needle aspiration or biopsy were recommended. The owner elected hemicastration and excisional biopsy. Testicular abscess was confirmed on gross examination, impression smears and histopathology; Staphylococcus simulans was isolated. Ceftiofur and anti-inflammatories were administered for nine days. Re-evaluation at seven months showed poor semen quality persisted. Antisperm antibodies were not present (2.7% and 8.2% IgG- and IgA-bound spermatozoa, respectively). Ultrasound revealed multiple hyperechoic small foci and an abnormal vascular pattern in the remaining testis. Differential diagnosis included orchitis, fibrosis, or calcification. Fine needle aspiration or biopsy was recommended. The owner elected to treat as orchitis with vitamin E and tulathromycin for six weeks. Nine months after hemi-castration, semen quality was still unacceptable. […]