Kathy Anderson, Extension Horse Specialist, University of Nebraska
The stallion manager participating in a cooled semen program must be very efficient in organizing the various mares, distributing quality semen, and ensuring sufficient supply of equipment at all times. The most important responsibility of the stallion manager is to provide mare owners with quality semen which survives the cooling process. Some stallions produce sperm cells which remain viable for extended periods of time after being cooled. However, some stallions' semen does not survive the cooling process at all.
At the start of each breeding season, and periodically throughout, the semen should be evaluated for concentration and motility of viable sperm cells. Additionally, each stallion's semen should undergo a 24-hour viability check to ensure it is a candidate for a cooled, transported semen program. The 24-hour viability test is important to determine not only if the semen is capable of being stored for transportation, but also which extender and antibiotic mixture works best for each particular stallion's semen. The viability check simply involves the same collection and processing as if it were to be transported, but the semen is reevaluated on-the-farm after being cooled for 24 hours. Stallion managers may also wish to evaluate the viability of the semen after a 36 and 48 hour cool storage.
Semen production capabilities between stallions can be highly variable. Some stallions produce highly concentrated, large volume ejaculates and can be collected every other day and others may need longer intervals between collections to produce quality ejaculates. The stallion manager must be familiar with the capabilities of each stallion and collect them to optimize their production of usable semen. The manager who continually monitors their stallions, should be able to give an accurate report on each stallions semen production capabilities.
