The effect of unilateral orchidectomy on the remaining testis of rams

Abstract

Five “Crioula” rams (18 months to 3 years old, weighing 17 to 51 kg) were unilaterally castrated and complete bilateral castration was carried out after a delay of 8 months. Sixty semen collections were made by electric shocks; 10 were made before hemi-castration, and the others 50 on days 1, 3, 60, 90, 120 and 240 after operation. By 240 days after hemi-castration, the weight of the remaining testis had increased by 33% above the weight of the testis previously removed. There was not the same effect on the weight of the epididymis. Associated with the enlargement of the remaining testis was a statistically greater rate of abnormalities of the middle-pieces and tails of spermatozoa and a decrease in motility, whereas the ejaculated volume and concentration remained almost constant. Head abnormalities were found to be significantly different between semen collections soon after hemicastration and 240 days.