Solano J, Orihuela A, Galina C S, Montiel F
Centro de Bachillerato Tecnológico Agropecuario, No. 8 de Xoxocotla Morelos, Mexico.
Physiol Behav. 2000 Dec;71(5):503-8. doi: 10.1016/s0031-9384(00)00367-x.
The effect of estrogen administered with norgestomet implants in the expression of behavioral estrous of Zebu cattle was studied in a herd of 18 cycling Brahman cows, in two trials. In the first and second trials, six different cows were treated with progestagen on successive days. In addition, in the first trial, estrogen injection was applied with the treatment. With the purpose of enhancing mounting behavior in treated and/or non-treated animals, on the third day of each trial, three other cows with an active CL were injected with 25 mg of PGF2alpha. All animals were examined three times a week by rectal ultrasound, and a blood sample was also taken for progesterone analysis. Sexual activity was monitored by a closed-circuit TV from 1500 to 0600 h. Direct observation was carried out from 0900 to 1200 h. A total of 15 cows displayed 36 mounting periods (11 with ovulation). Twenty-five annovulatory estrous periods were observed, 77% supported by large follicles. More cows (66% vs. 16%) showed mounting activity when estradiol valerate was used as part of the progestagen treatment (P=.03). Ovulation rate in response to the effect of norgestomet implant was 16%, independent of treatment. It is concluded that estrogen administered with norgestomet implants increases the expression of behavioral estrous in Bos indicus cattle but does not improve ovulation rate.
在两项试验中，对18头处于发情周期的婆罗门奶牛群进行研究，以探究雌激素与诺孕美特埋植剂联合使用对瘤牛行为发情表现的影响。在第一次和第二次试验中，连续几天对6头不同的奶牛进行孕激素处理。此外，在第一次试验中，在处理时注射雌激素。为了增强处理和/或未处理动物的爬跨行为，在每次试验的第三天，对另外3头有活性黄体的奶牛注射25毫克前列腺素F2α。每周通过直肠超声对所有动物检查三次，同时采集血样进行孕酮分析。从15:00至06:00通过闭路电视监测性活动。在09:00至12:00进行直接观察。共有15头奶牛出现36个爬跨期（其中11个伴有排卵）。观察到25个无排卵发情期，77%有大卵泡支持。当戊酸雌二醇作为孕激素处理的一部分时，更多奶牛（66%对16%）表现出爬跨行为（P = 0.03）。对诺孕美特埋植剂作用的排卵率为16%，与处理无关。得出的结论是，雌激素与诺孕美特埋植剂联合使用可增加印度瘤牛行为发情的表现，但不能提高排卵率。
