注射国产LRH-A对产后母牛卵巢活动、发情和受胎的作用

<正> 引言 促性腺激素释放激素(GnRH)是下丘脑神经内分泌细胞分泌的一种释放激素。由于本身结构和功能上的特点,自七十年代初人工合成后,GnRH及其类似物被广泛用于牛繁殖的研究和生产中。国外有报道认为GnRH有促进产后母牛发情周期恢复,缩短产后空怀天数等作用。国内用LRH-A提早牦牛产后发情和受胎收到良好效果。

Effect of injecting GnRH analog LRH-A on the ovarian activity,estrus and conception rate of postpartum dairy cows

56 healthy Black and White dairy cows were randomly alloted to four treatment groups, receiving 0, 100, 300, 500, meg of GnRH analog LRH-A as a single injection (i. m.) on the 20th day postpartum. Progesterone was measured by RIA in milk samples collected once every three days (5-7 cows per group). All cows were palpated per rectum before and after treatment. Compared with group I, intervals from calving to first ovulation in groups II and III were shortened (P <.01, P <.05 respectively) .Calving to conception intervals in groups II and III were also shorter than in group I, being 22.29, and 21 days (P<.01) repectively. The numbers of corpus Luteum and follicles increased significantly (P<0.01), and the progesterone concentration became higher after treatment (>lmcg/10 ml milkfat) in groups II, III and Ⅳ. The first ovarian cycles following treatment were 15.6, 14.5 and 22,4 days respectively in those groups.