Cryoresistance of stallion sperm in different months of the year

It is known that the seasonality of reproductive function is much more pronounced in mares than in stallions. The mare goes through an anestrus period in autumn and winter, while spermatogenesis in stallions continues throughout the year. Therefore, studies of cryoresistance of stallion sperm in different months of the year are relevant. The aim of the study was to study the cryoresistance of stallion sperm in different months of the year when creating cryopreservation of genetic material with intensive breeding use of sires. The cryoresistance of the sperm of stallions with their intensive breeding use was the best from September to December during sexual rest. The highest incidence of sperm was in December, which is 0.44% more than in October, 5.12% more than in November, 7.62% more (P<0.05) than in September, 20.53% more (P<0.01) than in January, 27.3% more (P<0.01) compared to February, 52.7% more (P<0.001) than in March, 137.9% more (P<0.05) than in April, 34.12% more (P<0.001) than in May, 23.5% more (P<0.001) than in June and 59.7% more (P<0.001) than in July. The survivability of sperms after thawing in a thermostat at 37°C for less than 3 hours was observed in March, April and July. The lowest sperm motility after defrosting was observed in April, which is 36.4% less (P<0.001) than in July, 38.6% less (P<0.001) than in May, 45.12% less (P<0.001) than in June, 50.1% less (P<0.001) than in in January, 52.6% less (P<0.001) than in February, 43.75% less (P<0.001) than in March, 53.8% less (P<0.001) than in September, 55% less (P<0.001) than in October, 54.4% less (P<0.001) than in November and 54.1% less (P<0.001) than in December. Based on the data obtained on the mobility of deconserved sperm doses, we mat expect the highest fertility from the genetic material that is harvested from September to December.

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