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won’t want to mount a mare or phantom. If there are any soundness issues, we can pursue those and try to get them corrected or under control before the breeding season, or at least have a plan for managing any musculoskeletal issues throughout the season. Some of these are common problems when a young horse comes off the track,” he says.
There are several steps involved in evaluat- ing the semen. “First, we need to collect the horse to clean out his epididymal reserves. The testicles continually produce sperm cells and they are stored in the epididymis until
they are needed for an ejaculate. If the sperm cells have been in epididymal storage awhile, they deteriorate and are not as viable as younger cells. The longer they are in storage, the poorer the quality of semen when the stal- lion ejaculates,” explains Coy.
“For this reason, we need to collect the horse at least 3 times - once a day for 3 days or at least every other day for 3 days, depend- ing on his temperament and how aggressive he is. The multiple collections serve two purposes. They clear out the old, stored sperm cells before the actual semen evaluation, and
Teasing a mare
also give you a chance to evaluate the horse’s behavior and work with him. He becomes more familiar with the routine and you are more likely to be able to collect him when you really need to get him collected. He’s had more experience in the breeding shed.”
When the pressure is on and mare owners start ordering semen, people may get frustrated if the stallion is slow or inexperienced and uncooperative. It’s easier to take the time you need during these early training periods. “It’s
a more relaxed setting and a better training session,” says Coy.
The early training sessions also allow for assessment of the young stallion regarding his breeding behavior. Is more experience with mares needed, or is he is too aggressive with them, or does he need a change of handlers? “You’ll find out if you need to muzzle him or if he requires a bite strap when mounting the phantom,” says Coy.
The stallion should be collected at least
3 times, and then 24 hours after that third collection the stallion should have an actual semen evaluation for breeding soundness. This will give a better idea about what this horse will actually be producing during the breeding season. “In some of the earlier training sessions, the horse might have an incomplete ejaculation if he is not comfortable or not yet sure of what he is doing. We want to make sure we have a complete ejaculation to evaluate during the actual examination. This is part of the reason for the other 3 and the prior training sessions.”
The object is to get a complete ejaculation. “Then the semen will be evaluated for motility, velocity, total numbers, and any major sperm defects that will significantly affect fertility.
In a typical breeding soundness exam, we
will collect the stallion and then an hour later collect him again. With these collections one hour apart, the second collection numbers will usually drop about half if you’ve cleaned out the epididymis from the previous three collec- tions. This gives us an idea about what his daily sperm output will be,” says Coy.
This can help you estimate how many mares the stallion will be able to breed or pro- vide semen for in a day. Consequently, you can project how many mares he might handle in his book for the season. “This might be 50 mares or 100 mares, or 200 mares, depending on the fertility of the stallion,” he says.
“After we collect the horse and the testicles are down and the scrotum is relaxed, we finish the breeding soundness evaluation by palpating and measuring the testicles. We palpate them to determine their consistency and size. This will also give us an idea how he compares to his peers - whether average, above average or below - compared to other young stallions. It is also
34 SPEEDHORSE, March 22, 2013
Teasing a mare
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