Consequences of adding gum Arabic as a cryoprotectant on motility and viability of frozen stallion semen.

The study explores the potential of using gum Arabic as an alternative cryoprotectant, replacing egg yolk, to freeze stallion sperm. It found that preheated gum Arabic could maintain sperm quality and fertility rates, suggesting its viability as an alternative protective substance for cryopreserving stallion sperm.

Research Design and Methodology

• This investigation consisted of two experiments where the effects of adding different levels of gum Arabic (GA), both nonheated and heated, to stallion semen were evaluated.
• The first experiment tested the addition of nonheated GA in three different concentrations: 3, 6, and 9 grams per 100 mL of diluents – this was done in an HF-20 extender, a commonly used solution for semen dilution and preservation.
• In the second experiment, the same levels of GA were added, but this time, they were preheated at 80°C for one hour.
• An HF-20 extender containing 10% egg yolk (EY) was used as a control for both experiments – this is a typical component in semen extenders for its cryoprotective capabilities.

Findings and Conclusions

• In the first experiment, sperm frozen in HF-20 with nonheated GA displayed a decrease in motility, integrity of sperm membranes, vitality rate, and acrosome integrity.
• However, when the GA was preheated, as in the second experiment, sperm retained better motility, with rates between 46-50%, and increased progressive motility, with a rate of 27%.
• The best fertility rate was achieved with frozen semen diluted in preheated 6% GA, showing a successful fertilization rate of 40% – comparable to the control semen rate. On the other hand, when frozen semen diluted in preheated 3% GA was used, the fertility rate dropped to 20%.
• The research concluded on a promising note, suggesting preheated GA as a potential alternative cryoprotectant to traditionally used substances like egg yolk for cryopreserving stallion sperm, given the maintained sperm motility and fertility rates.