Sperm abnormalities and histopathological changes in the testes in Crj:CD(SD)IGS rats

Area of Science:

• Reproductive Biology
• Spermatogenesis
• Animal Models

Background:

• Step 19 spermatid retention in seminiferous tubules is a potential indicator of male reproductive health.
• Understanding this retention is crucial for interpreting sperm analysis data in non-treated animal models.

Purpose of the Study:

• To investigate the relationship between step 19 spermatid retention and epididymal sperm quality in untreated rats.
• To analyze sperm morphology and motility using computer-assisted sperm analysis (CASA) in relation to spermatid retention incidence.

Main Methods:

• Morphological examination of epididymal spermatozoa.
• Computer-assisted sperm analysis (CASA) for motility and kinematic parameters.
• Quantification of step 19 spermatid retention in Stage IX-XI seminiferous tubules.

Main Results:

• All 50 untreated rats exhibited step 19 spermatid retention, with varying incidences.
• High incidence retention (HIR) males showed significantly more morphologically abnormal sperm (e.g., amorphous heads) compared to low incidence retention (LIR) males.
• HIR males displayed severely reduced sperm motility, velocity, and other CASA-derived parameters compared to LIR males.

Conclusions:

• Step 19 spermatid retention is a frequent finding in untreated Crj:CD(SD)IGS rats.
• A strong correlation exists between high spermatid retention and impaired sperm quality, including morphology and motility.
• These findings suggest that spermatid retention can impact sperm analysis outcomes and reproductive potential.