Influence of the year's season on the testicular structure in sheep bred in southern Piaui, Brazil

ABSTRACT:

To evaluate influence of the year season related with the testicular structure of cross bred sheep, the testes of ten 2 to 3-year-old sheep were sectioned and fixed in for 24 hours in bouin's solution. The fragments were subjected to histological processing, embedded in paraffin and stained with hematoxylin-eosin. The volumetric proportion of testicular compartments, the seminiferous tubules, seminiferous epithelial height and frequency of the seminiferous epithelium stages of the cycle were evaluated. Data were subjected to analysis of variance at 5% probability. The results showed that all values studied were influenced by year's season. The tubular diameter was 143.98±17.83 and 170.37±26.64μm, the seminiferous epithelium height was 44.92±9.23 and 50.06±13.61μm, and the testicle parenchyma volume density was 78.32±16.68 and 80.13±15.14% in the dry and rainy periods, respectively. The germ cells and Sertoli cells quantification showed that all values were higher in the rainy season compared with the dry season. It can be concluded that the year season interfered in the testicular structure, given that all values showed significant differences between the seasons, as the values were more pronounced during the rainy season.

INDEX TERMS: Spermatogenesis; testis; small ruminants; sheep