Testicular weight, Sertoli cell number, daily sperm production, and sperm output of sexually mature rabbits after neonatal or prepubertal hemicastration.

The present study was conducted to investigate the influence of hemicastration and age at hemicastration on the subsequent testicular development of male rabbits through sexual maturity. Thirty New Zealand white rabbits were left intact or were hemicastrated on Day 35, 49, 77, or 105 postconception. Beginning at 7 mo of age, ejaculates were collected every other day for 1 mo, and the last ten ejaculates were used to quantify daily sperm output. At 8 mo, the rabbits were killed and their carcases, testes, testicular capsules, and epididymides were weighed. Testicular tissue was processed for quantification of sperm production rates by enumeration of homogenization-resistant spermatids and via histometric evaluation. Regardless of the age at hemicastration, this manipulation did not alter the development of the remaining testis as assessed from testis weight, numbers of Sertoli cells per testis, daily sperm production, or sperm output (p > 0.05). On the basis of these findings, it would appear that the development of the spermatogenic capacity of the remaining testis of the rabbit is not altered appreciably by hemicastration at a young age.