Pelvic nerve dysfunction in sheep

Marked urinary bladder distension, hydroureters, bilateral hydronephrosis and peri-renal fluid accumulation were identified ultrasonographically in two rams from the same farm over two years. One ewe also showed urine staining, bladder distension and incontinence for six months. There were normal tail and rectal muscle tone, and normal perineal and pelvic limb reflexes in all sheep. A presumptive diagnosis of pelvic nerve dysfunction causing detrusor atony and bladder distension, with secondary, pressure-induced hydronephrosis, is suggested. Detailed dissection at necropsy found no evidence of urethral obstruction in either ram; the ewe was sold fat after six months’ observation. Pelvic nerve dysfunction may readily be confused with partial urethral obstruction and this condition may be more widespread than previously considered.