Experimentally induced testicular alterations in boars: histological and ultrastructural findings.

Nine mature boars (8 experimental and one control) were used to study the effects of elevated testicular temperature. The scrotum was covered by a textile-aluminium foil insulation for 100 hours. The boars were divided into 4 groups and were slaughtered at the end of scrotal insulation (group I), 10 days (group II), 20 days (group III) and 40 days (group IV) after scrotal insulation. In groups I and II changes were seen among primary spermatocytes and spermatids, although the changes in group II were more severe. In group III the changes were restricted to the spermatids and in group IV most of the tubules were normal. The epididymal spermatozoa showed slight changes in group I, severe changes in groups II and III and were normal in group IV. The results indicated that spermatogonia were not affected, whereas primary spermatocytes seemed to be the most susceptible germ cell type. Scrotal insulation produced restricted damage that was reversible when the insulation was removed and turned out to be a suitable method to study regeneration processes in the testis of boars.