Dailey R A, Price J C, Simmons K R, Meisterling E M, Quinn P A, Washburn S P
J Dairy Sci. 1986 Apr;69(4):1110-4. doi: 10.3168/jds.S0022-0302(86)80508-2.
A field study using 322 lactating dairy cows in seven commercial and two university herds was conducted to determine if treatment with estradiol benzoate 40 to 48 h after treatment with prostaglandin F2 alpha would enhance synchronization of estrus. Estrogen treatment tended to increase the proportion of cows in estrus within 5 d (synchronized) after prostaglandin treatment (66.9% versus 58.9%). Of synchronized cows, a greater proportion treated with estrogen (66.9%) were in estrus on d 3 than those not receiving estrogen (48.2%). First service conception rate (31.9%) and interval to second service (35.6 d) were not affected by treatment with estrogen. Milk progesterone was measured in university herds. More cows with milk progesterone concentrations greater than or equal to 8 ng/ml were synchronized (75.4%) than those with less than 8 ng/ml (63.3%). Treatment with estrogen increased synchrony of cows with high progesterone (90.3%) more than prostaglandin alone (60.0%). Based on progesterone concentrations at breeding and 22 to 24 d later, estimated conception rate was 58.7%, and net conception rate based on palpation was 41.3%. Tighter synchrony of estrus can be achieved by using estradiol benzoate 40 to 48 h after prostaglandin. Concentrations of milk progesterone might predict success of treatment.
在七个商业牛群和两个大学牛群中使用322头泌乳奶牛进行了一项实地研究，以确定在用前列腺素F2α治疗后40至48小时用苯甲酸雌二醇治疗是否会增强发情同步性。雌激素治疗倾向于增加前列腺素治疗后5天内发情（同步）奶牛的比例（66.9%对58.9%）。在同步发情的奶牛中，接受雌激素治疗的奶牛在第3天发情的比例（66.9%）高于未接受雌激素治疗的奶牛（48.2%）。首次输精受胎率（31.9%）和第二次输精间隔时间（35.6天）不受雌激素治疗的影响。在大学牛群中测量了牛奶孕酮。牛奶孕酮浓度大于或等于8 ng/ml的奶牛同步发情的比例（75.4%）高于浓度低于8 ng/ml的奶牛（63.3%）。与单独使用前列腺素相比，雌激素治疗使高孕酮奶牛的同步发情率提高得更多（90.3%对60.0%）。根据配种时和22至24天后的孕酮浓度，估计受胎率为58.7%，基于直肠检查的净受胎率为41.3%。在前列腺素治疗后40至48小时使用苯甲酸雌二醇可以实现更紧密的发情同步。牛奶孕酮浓度可能预测治疗的成功率。
