Testicular Histopathology and Spermatogenesis in Mice with Scrotal Heat Stress

Chronic heat stress-induced testicular damage and function therefore adversely affect their reproduction. Some research shows that heat stress has a negative effect on histopathological features of testicular tissue structure and spermatogenesis. An animal model was used to evaluate the effect of heat stress on testicular histology changes and spermatogenesis. The mouse model of heat stress was established by submerged in a pre-warmed incubator. The testes’ tissue was fixed and stained with hematoxylin–eosin (H&E) for quantitative analysis of histopathological alterations and spermatogenesis according to Johnson scoring system. Mice exposed to heat stress exhibited degenerated and disorganized features of spermatogenic epithelium and reduced spermatogenic cells. Heat stress exposure shows a significantly reduced Johnson score compared to the control condition. The percentage of high Johnsen score points was decreased in heat-stress exposure mice, while the ratio of low Johnsen score points was gradually increased. This chapter describes a mouse model for studying the male reproductive system and applies the Johnsen scores system to assess testicular histopathology in the seminiferous tubule cross-section. Collectively, this chapter indicated a negative impact of heat stress on mouse spermatogenesis as well as the human reproductive system.