Influence of season and frequency of ejaculation on production of stallion semen for freezing.

The researchers conducted a year-long study on six stallions to determine the ideal season and frequency of ejaculation for collecting semen to be frozen. They concluded that winter seems to be the best season for production, but frequency of ejaculation doesn’t significantly impact the final quality of the frozen semen.

Research Methodology

• The researchers collected semen from six stallions, three horses and three ponies, alternatively three times a week and daily in every week for a year.
• This semen was evaluated based on various parameters and then frozen.
• After the year-long experiment, all the samples were thawed.

Observations on Fresh Semen

• When the semen was evaluated fresh during collection, it was observed that the winter season was linked to lesser sexual activity and smaller volumes of spermatozoa and gel.
• A particularly higher sperm concentration and lower motility was observed during the winter season in comparison to the spring and summer.
• Increased ejaculation frequency led to decreased semen volume and concentration of spermatozoa in ejaculate. However, there was a slight improvement in sperm motility.

Analysis of Thawed Semen

• The researchers examined the quality of thawed semen using video analysis, microscope motility estimations, and two different staining techniques for assessing vitality.
• No changes were observed based on the frequency of ejaculation.
• The semen that was collected in winter showed the best freezability. However, the difference was not large compared to the variability observed between different stallions.

Conclusions

• The researchers concluded that while the optimal season to collect semen from stallions for freezing seems to be winter, the frequency of ejaculation did not have a significant impact on the final quality of the thawed semen.
• Moreover, they also observed that ensuring optimal frequency and season did not transform a stallion that was a ‘bad freezer’ (i.e., its semen did not freeze well) into a good one.