Everett R W, Bean B, Foote R H
J Dairy Sci. 1978 Jan;61(1):90-5. doi: 10.3168/jds.S0022-0302(78)83555-3.
Data from 5033 ejaculates during 1 yr from 55 mature Holstein bulls were analyzed to determine the effects of ejaculate number, days between ejaculates, month of the year, solunar periods, and sires on spermatozoal output and seminal characteristics. First ejaculates contained 49.7% more sperm and 40.8% more sperm per ml than second ejaculates. Increasing the interval between collections from 2 to 6+ days resulted in 45.9% more sperm per ejaculate, 31.0% more sperm per ml. and 14.0% greater volume. However, daily sperm output was highest when bulls were ejaculated most frequently. Lowest semen output was in February and March, associated with a decrease in sperm per ml. Highest semen output was in April and June, associated with the highest concentration of sperm per ml. Solunar periods had no effect on any measure of semen output. The concentration of sperm per ml varied more than the volume per ejaculate and had the largest influence on variation in total sperm harvested per ejaculate. Frequency of ejaculation was a major factor in total sperm harvested per bull per year.
对55头成年荷斯坦公牛在1年期间的5033份射精样本数据进行了分析，以确定射精次数、射精间隔天数、年份月份、日月周期和公牛对精子产量及精液特征的影响。首次射精的精子数量比第二次射精多49.7%，每毫升精子数量多40.8%。将采集间隔从2天增加到6天以上，每次射精的精子数量增加45.9%，每毫升精子数量增加31.0%，精液体积增加14.0%。然而，当公牛射精最频繁时，每日精子产量最高。精液产量最低的是2月和3月，这与每毫升精子数量减少有关。精液产量最高的是4月和6月，这与每毫升精子浓度最高有关。日月周期对精液产量的任何指标均无影响。每毫升精子浓度的变化比每次射精的精液体积变化更大，并且对每次射精采集的总精子数量变化影响最大。射精频率是每头公牛每年采集的总精子数量的主要因素。
