Fractionated semen collection as a tool to rescue fertility in stallions with seminal vesiculitis.

The research focuses on applying the practice of fractionated semen collection to improve the fertility of stallions suffering from seminal vesiculitis, an inflammation of the seminal vesicles. The study revealed better post-cooling sperm motility results, as well as improved rates of pregnancy, when the first fractions of ejaculate were used.

Overview of the Study

• The research involved 18 ejaculates from six different stallions, diagnosing each with seminal vesiculitis. Each ejaculate was split into three fractions: Fraction A (first two jets), Fraction B (third and fourth jets), and Fraction C (the remaining jets).
• These fractions were analyzed for any abnormalities. In addition, bacterial aerobic cultures and cellular studies were conducted.
• Lastly, the semen fractions were extended and cooled to 5 degrees Celsius.

Findings

• Fraction A showed no bacterial presence and no macroscopic or microscopic abnormalities. The post-cooling sperm motility results were notably higher for this fraction compared to the other two.
• Fraction B showed bacterial presence in two cases and evidence of polymorphonuclear neutrophils (PMNs) but no visible abnormalities.
• Fraction C held positive bacterial cultures, a purulent (pus-like) appearance and degenerated PMNs, similar to characteristics found in the whole semen initially.

Testing the Concept

• 20 mares were inseminated with 1 billion sperm cells from Fraction A, following a 24-hour cooling period at 5 degrees Celsius. Altogether, about 8 cycles occurred per stallion.
• The first-cycle pregnancy rates fluctuated between 66% to 86%. Importantly, no cases of endometritis, inflammation of the lining of the uterus, were reported among the non-pregnant mares.

Conclusion

• The use of fractionated semen collection could feasibly help produce contamination-free semen, thereby significantly improving the fertility rates of stallions with seminal vesiculitis.