张拴林，黄应祥，岳文斌*，刘 强
（山西农业大学动物科技学院，山西 太谷030801）
摘 要：选择发情周期为21天、产后9天~63天的第一胎中国荷斯坦奶牛24头，分为三组，设置三个能量水平，研究对奶牛生殖激素分泌的影响。结果表明:母牛的能量状况与促乳素的相关系数r=－0.9618(P＜0.01),与生长激素的相关系数r=－0.7435(P＜0.01),在能量负平衡阶段，能量状况与胰岛素值为负相关，在能量正平衡阶段，能量状况与胰岛素值为正相关。发情持续期前第7周的能量值与雌二醇浓度相关系数r=0.9675(P＜0.01)，与孕酮的相关系数r=－0.7129，黄体期前第7周和第8周的能量值与雌二醇的相关系数分别为0.8099和0.5775，与孕酮的相关系数分别为0.8263和0.6502，因此，在分娩前2周提高日粮能量水平，不仅会提高发情鉴定率，更能提高受胎率，对于高产奶牛，同时控制产后2周泌乳量，可有效缓解能量负平衡，达到提高发情鉴定率和受胎率的目的。
|
|
Effect of Diet Energy Levels on Reproductive Hormones in Dairy Cattle
ZHANG Shuan-lin，HUANG Ying-xiang，YUE Wen-bin*，LIU Qiang
（College of Animal Science and Technology, Shanxi Agricultural University, Taigu 030801, Shanxi , China）
Abstract：24 first lactation Chinese Holstein Dairy Cattle were used to investigate the effect of diet energy level on reproductive hormones. The energy balance was highly correlated with PRL〔r=－0.9618 (P＜0.01)〕, it was correlated with GH (r=－0.7435) also. The energy balance was negatively correlated with insulin in the phase of negative energy balance; whereas it was positively correlated with insulin in the phase of positive energy balance. The correlation coefficient between energy balance of the seventh week prior to duration of estrus and estradiol is 0.9675(P＜0.01), while the correlation coefficient between energy balance and progesterone is －0.7129. The correlation coefficient between energy balance of the seventh week, and eighth week prior to optimum luteal phase and estradiol are 0.8099 and 0.5775, respectively, the correlation coefficient of progesterone are 0.8263 and 0.6502, respectively,so increasing energy level before calving , it can not only to increase heat detection rate , but also to increase conception rate. In order to increase heat detection rate and conception rate , we can control milk yield within two weeks of postpartum for high producing cows at the same time.
|
