Schuenemann Gustavo M, Edwards J Lannett, Davis Mark D, Blackmon Heather E, Scenna Fernando N, Rohrbach Nancy R, Saxton Arnold M, Adair H Stephen, Hopkins Fred M, Waller John C, Schrick F Neal
Department of Animal Science, University of Tennessee, Knoxville, USA.
Theriogenology. 2005 Mar 15;63(5):1407-18. doi: 10.1016/j.theriogenology.2004.07.014.
Sixteen yearling bulls were utilized to investigate administration of ergotamine tartrate on semen parameters, fertilization, and endocrinology. Bulls were allotted to a control diet of cracked corn, corn silage, and soybean meal (CON, n = 8) or a diet supplemented daily with 40 microg/kg body weight of ergotamine tartrate (ET, n = 8). Blood samples, average daily gain, scrotal circumference and rectal temperatures were collected every 14 day. Semen samples were obtained every 60 day and evaluated for motility and morphology. Scrotal temperatures were obtained by thermography immediately before electroejaculation. Semen from a subset of bulls from each treatment was also evaluated for in vitro fertilization. Administration of ET increased rectal temperature and resulted in lower scrotal temperatures compared to CON bulls (P < 0.05). However, prolactin, scrotal circumference, testosterone, and semen motility and morphology did not differ between groups throughout the experimental period (224 day). Cleavage rates of embryos derived from in vitro fertilization (IVF) with semen of bulls, fed with ET, were reduced compared to CON (P < 0.05); however, development of cleaved embryos to blastocyst did not differ between treatments. In conclusion, extended exposure of bulls to ET appeared to reduce fertilization potential of sperm.
选用16头一岁公牛来研究酒石酸麦角胺对精液参数、受精及内分泌的影响。公牛被分配到由碎玉米、玉米青贮饲料和豆粕组成的对照日粮组（CON，n = 8）或每日补充40微克/千克体重酒石酸麦角胺的日粮组（ET，n = 8）。每14天采集一次血样、记录平均日增重、阴囊周长和直肠温度。每60天采集一次精液样本，并对其活力和形态进行评估。在电刺激采精前立即通过热成像法获取阴囊温度。还对各处理组中一部分公牛的精液进行体外受精评估。与CON组公牛相比，ET组公牛直肠温度升高，阴囊温度降低（P < 0.05）。然而，在整个实验期（224天）内，两组间催乳素、阴囊周长、睾酮以及精液活力和形态并无差异。与CON组相比，用ET组公牛精液进行体外受精（IVF）得到的胚胎卵裂率降低（P < 0.05）；不过，处理组间分裂胚胎发育至囊胚的情况并无差异。总之，公牛长期接触ET似乎会降低精子的受精潜能。
