EFFECT OF DIETARY MONENSIN ON OVARIAN RESPONSE FOLLOWING GONADOTROPIN TREATMENT IN PREPUBERAL HEIFERS
EFFECT OF DIETARY MONENSIN ON OVARIAN RESPONSE FOLLOWING GONADOTROPIN TREATMENT IN PREPUBERAL HEIFERS
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DOI：
10.2527/jas1980.513692x
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发表时间：
1980-01-01
影响因子：
3.3
通讯作者：
CARROLL, LH
中科院分区：
文献类型：
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作者：
BUSHMICH, SL;RANDEL, RD;CARROLL, LH
青春期前的夏洛莱犬.times。 Brahman-Hereford 小母牛 (20 头) 被随机分配每天每头饲喂含有 0 mg (C) 或 200 mg (M) 莫能菌素钠的浓缩物。沿海狗牙根干草随意饲喂。两组的平均日增重相似。每头小母牛在第 22-26 天的 0800 和 2000 小时接受 1 毫克猪卵泡刺激素 (FSH-P)（Armour）（总共 10 毫克），并在第 27 天接受 2500 IU 人绒毛膜促性腺激素 (HCG)。第 30 天进行侧腹剖腹手术，检查卵巢，并在第 37 天进行卵巢切除术。平均卵巢大小.+-.第 15 天的标准误差为 3730 .+-。 66 mm3 和 1848 .+-。通过直肠触诊测量，M 组和 C 组分别为 55 mm3 (P < 0.025)。第 30 天测量的排卵部位数量为 9.1.+-。 2.2 和 4.9.+-。 M 组和 C 组每头小母牛分别为 1.8 (P < 0.01)。第37天卵巢切除后，饲喂M的小母牛与对照组相比，具有更大的卵巢重量（P < 0.05）、更多的黄体（CL）（P < 0.05）、更大的黄体总重量（P < 0.05）、更多的卵泡（P < 0.01）以及更大的卵泡液（P < 0.05）和基质重量（P < 0.025）。通过分光光度法分析 CL 的黄体酮含量。饲喂 M 的小母牛的 CL 稍大（P < 0.10），孕酮浓度与对照的 CL 相似。这导致 M 小母牛中的黄体孕酮/CL 和每只小母牛的黄体孕酮高于对照组。青春期前的小母牛饲喂 M 后，与对照组相比，M 会导致瘤胃发酵和挥发性脂肪酸产生发生预期的变化，显示出卵巢对促性腺激素的反应增强。
Prepuberal Charolais .times. Brahman-Hereford heifers (20) were randomly assigned to be fed a concentrate containing either 0 mg (C) or 200 mg (M) monensin sodium per head per day. Coastal bermudagrass hay was fed ad lib. Average daily gain was similar for the 2 groups. Each heifer received 1 mg of porcine follicle stimulating hormone (FSH-P) (Armour) at 0800 and 2000 h on days 22-26 (10 mg total) and 2500 IU human chorionic gonadotropin (HCG) on day 27. Flank laparotomy was performed on day 30, for examination of ovaries and ovariectomy was performed on day 37. Average ovarian size .+-. standard error at day 15 was 3730 .+-. 66 mm3 and 1848 .+-. 55 mm3 for groups M and C, respectively (P < 0.025), as measured by rectal palpation. Numbers of ovulation sites measured on day 30 were 9.1 .+-. 2.2 and 4.9 .+-. 1.8 per heifer for groups M and C, respectively (P < 0.01). After ovariectomy on day 37, heifers fed M had greater ovarian weight (P < 0.05), more corpora lutea (CL) (P < 0.05), greater total luteal weight (P < 0.05), more follicles (P < 0.01) and greater weight of follicular fluid (P < 0.05) and stroma (P < 0.025) than controls. CL were analyzed for progesterone content by spectrophotometric procedures. Heifers fed M had slightly larger CL (P < 0.10) with progesterone concentrations similar to those in CL from controls. This resulted in more luteal progesterone/CL and more luteal progesterone per heifer in M heifers than in controls. Prepuberal heifers fed M, which caused expected shifts in rumen fermentation and volatile fatty acid production, exhibited an enhanced ovarian response to gonadotropins compared to controls.