Examination of paraffin-embedded testes of domestic cats and dogs by light and scanning electron microscopy

Abstract

This study was designed to determine the appropriate section thickness for SEM analysis of paraffin-embedded testes. This study used paraffin-embedded testes from 6 adult cats and 6 adult dogs. Tissue blocks were cut into 10, 20, and 40 mu m thick sections and analyzed by SEM. In addition, seminiferous tubule and lumen diameter and germinative epithelium height were measured in 10 and 20 mu m thick paraffin sections. Measurements from 10 and 20 mu m thick paraffin sections showed that the height of the germinative epithelium and the diameter of the lumen and tubules were similar between cats and dogs (p > 0.05). In cats and dogs, tubule diameter and germinative epithelium height were higher in the 10 mu m thick paraffin sections compared to the 20 mu m thick paraffin sections. However, in both species, the lumen diameter was greater in the 20 mu m thick paraffin sections than in the 10 mu m thick paraffin sections (p < 0.05). Unlike 40 m thick paraffin sections, 10 and 20 mu m thick paraffin sections allowed the structural features of the testes to be examined. Additionally, 10 mu m thick paraffin sections were ideal for histometric measurements, while 20 mu m thick paraffin sections were suitable for detailed examination of late spermatids. The present study showed that testes may be examined in detail by SEM from 10 and 20 mu m thick paraffin sections. In addition, this study may contribute to the design of new studies to reveal the missing three-dimensional structures of paraffin-embedded testicular tissues stored in tissue archives by analyzing them by SEM.