Unilateral and bilateral cryptorchidism and its effect on the testicular morphology, histology, accessory sex organs, and sperm count in laboratory mice

Background: Experimental unilateral cryptorchidism (ULC) and bilateral cryptorchidism (BLC) are excellent methods to study undescended testis in relation to spermatogenesis against a temperature gradient. Objectives: In case of ULC, it is possible to compare the testicular functions between normal condition and cryptorchidism in the same animal, whereas BLC shows the necessity of testicular androgens for proper maintenance of reproductive structures and functions. Materials and Methods: In the present study, experimental ULC and BLC was done on same-aged adult mature male mice and kept for 15 days and 30 days, respectively, to observe the changes due to the induced cryptorchidism on the different reproductive organs, viz., the testis and accessory sex organs along with epididymal sperm count. Reproductive tissues were collected from individual animals and histopathological studies of testis were done to investigate different cytological changes. Results: The size of the testes and accessory sex organs were found to be significantly reduced in BLC mice, whereas only testicular weight reduction was observed in ULC mice. Histopathological studies showed degenerative changes throughout the seminiferous tubules. Conclusion: Thus, the present investigation showed compensatory androgen production in ULC mice, whereas absence of androgen mediated reproductive functions in BLC animals.