Clinical, pathological and histopathological findings in lambs implanted with a growth promoting product containing progesterone and oestradiol.

Six live wether lambs and the urogenital tracts of 4 others from 4 separate farms were presented for examination. In each case the wethers had been implanted several weeks previously with a growth promoting product containing progesterone and oestradiol. The affected wethers presented with dorsal retroflexion of a markedly distended bladder which caused persistent straining, bulging of the perineal muscles and rectal prolapse. Enlargement of the bulbo-urethral glands and seminal vesicles, with an increase in the volume and viscosity of the secretion of the bulbourethral glands was evident on gross examination. Histopathological examination of the prostate and bulbourethral glands revealed cystic dilation of the glands and hyperplasia and squamous metaplasia of the glandular epithelium. Desquamated cells and eesinophilic-staining material were present in many of the dilated lumens. In the seminal vesicles, interstitial fibrosis had resulted in the obliteration of large areas of glandular tissue. The enlargement of the prostate and bulbo-urethral glands, and particularly the increased viscosity of the gland secretions, probably hindered urination, resulting in only partial evacuation of the bladder. Attempts to urinate by active contraction of the abdominal muscles may have accounted for the dorsal retroflexion of the distended bladder. The oestrogenic influence of the growth implants is thought to be responsible for these changes.