【作者】 常仲乐；

【导师】 谭景和；

【作者基本信息】 山东农业大学 ， 生物化学与分子生物学， 2008， 博士

【摘要】 本研究通过对7只鲁北白山羊秋季正常发情季节、春季发情季节及夏季高温休情每天卵巢上卵泡发育的超声波扫描观察,研究了鲁北白山羊正常发情季节体内卵泡发育的基本规律,两个繁殖季节间体内卵泡发育规律的差异和夏季高温休情期鲁北白山羊卵巢上卵泡发育的规律并比较了鲁北白山羊秋季卵巢上卵泡发育规律与夏季高温休情期体内卵泡发育规律的异同;结果表明山羊的发情周期中体内小卵泡每天均有发生,大卵泡呈周期性出现,能够发育成大的优势卵泡的卵泡出现呈现周期性,即山羊卵巢上卵泡是以卵泡波的形式的发生。鲁北白山羊山羊秋季排卵间隔内主要含有4个卵泡波(60%),排卵间隔内卵泡波的数量与排卵间隔的长短呈正相关r=0.619;卵泡波内优势卵泡生长与从属卵泡的生长存在明显差异,优势卵泡的生长过程中均存在快速生长期,而从属卵泡不存在快速生长期。通过对不同直径卵泡数量的比较发现3.8-4.5mm的卵泡数量呈急剧减少趋势,能够生长至>4.5mm直径的卵泡的数量与生长至5.0mm以上卵泡的数量差异不显著,因此认为山羊的卵泡发生卵泡选择的直径范围应该在3.8-4.5mm,而直径>4.5mm后便可以进入卵泡的优势化状态。鲁北白山羊春、秋两个发情季节间排卵间隔的长度无差异,但排卵间隔内所含卵泡波的数量存在显著差异,秋季的排卵间隔主要含有4个卵泡波卵,占全部排卵间隔的60%,而春季排卵间隔主要含有3个卵泡波,占全部排卵间隔的60%。在高温休情季节,鲁北白山羊卵巢上的卵泡发育仍以卵泡波的形式发育,卵泡波间隔的长短在温度较低的阶段无差异,但至8月温度进一步升高的情况下卵泡波间隔延长;高温休情期卵泡波中的优势卵泡直径小于正常排卵间隔中第一卵泡波和排卵卵泡波中优势卵泡的直径,高温休情期的卵泡波中的4.0-4.5mm的卵泡数量显著高于繁殖季节各卵泡波中4.0-4.5mm的卵泡数。鲁北白山羊与沂蒙黑山羊的排卵间隔无显著差异,在秋季排卵间隔所含卵泡波数在两品种间无差异,排卵卵泡波募集的卵泡数间无显著差异,但鲁北白山羊排卵卵泡波中优势卵泡数量及排卵卵泡数均显著高于沂蒙黑山羊,鲁北白山羊排卵卵泡波中优势卵泡的排卵率也显著高于沂蒙黑山羊。这两个品种都存在倒数第二个卵泡波中优势卵泡排卵,但鲁北白羊倒数第二个卵泡波产生排卵卵泡的比例显著高于沂蒙黑山羊。在排卵卵泡波卵泡直径生长至4mm后利用低剂量FSH处理单胎的沂蒙黑山羊可以显著地增加单胎山羊的排卵卵泡波中能生长至排卵直径的卵泡数量,同时也能够提高沂蒙黑山羊的排卵数。通过不同处理方案对波尔山羊实施超数排卵,发现6-7mg国产激素4天递减剂量和240mg加拿大进口激素4天递减剂量处理效果优于其它方案。在对年龄、季节及重复处理等影响超数排卵效果的因素分析表明,秋季(9-11月)的排卵数、可用胚率和胚胎移植妊娠率都最高;冬季(12-2月)妊娠率显著低于春(3-5月)秋两季。12-35月龄山羊的排卵数、可用胚率和胚胎移植后妊娠率最高,7-11月龄山羊的排卵数、可用胚率、胚胎移植后妊娠率和超排反应率都最低。重复超排一次排卵数和可用胚率与初次超排差异不显著,但重复处理两次的排卵数和可用胚率显著下降。排卵数多少对受精及可用胚率无显著影响。一次移植2枚胚胎与移植1枚胚胎的受体分娩率差异不显著,移植2枚胚胎受体双羔率显著高于移植1枚胚胎,但移植2枚胚胎的胚胎产羔率低于移植1枚胚胎的胚胎产羔率。更多还原

【Abstract】 Transrectal utrasonography of ovaries were performed each day in prolific Lubei White does(n=7) during 3 oestrous cycle in two different breeding seasons in Autumn and in Spring, and for 32 days in the middle of anoetrous season in Summer to record the number and size of all follicles≥3.0mm in diameter.And Transrectal utrasonography of ovaries were performed each day in non-prolific Yimeng Black does(n=6) and prolific Lubei White does(n=7) during 3 oestrous cycle in the breeding seasons in Autumn to record the number and size of all follicles≥3.0mm in diameter. Follicular data were then classified by the number of follicular waves to determine the folicular diameter range of follicular diviation.The observed number of growing identified 4-mm follicles per day differed (P<0.05) from randomness, indicating that follicles, on the average, emerged in groups (waves). Averaged over all interovulatory intervals, the number of 3-mm follicles on each day that later reached≥5 mm followed a pattern of significant peaks on Days 0 (ovulation), 4-5,10 and14-16. A follicular wave was defined by consecutive days of entry of follicles≥5 mm into the wave, and the day of emergence was defined as the first day that the≥6 mm follicles were 3 mm. Follicular number decreased rptly in the diameter range from 3.8mm to 4.5mm, and the folliclle quantity decreased unsignificantly in the the diameter range >4.5mm. 4 waves were observed in 12(60%) interovulatory intervals in Autumn, while 3 waves in 6(60%) interovulatory intervals in autumn in Spring, and no difference were found in the interovulatory intervals of the Lubei White does between Autumn and Spring. The follicular wave were also observed in the anoestrous season in Summer, the interwave intervals is 4.4 in first half month during the anoestrous season in Summer,while in another half monthe it proloned significently. No difference about recruitment phase and follicular numbers emerged during the period of ovulatory wave recruitment phase in ovulatory wave were found between the two breeds of goat differing in prolificacy. However the dominant follicular number and ovulatory rate were higher significently in prolific Lubei White does. And the penultimate wave found contained ovulatory follicles in 11.1% of non-prolific Yimeng Black does but in 35% of prolific Lubei White does.80mIU or 160 IU FSH per day per goat was intravenous injected to the two experiment group of non-prolific Yimeng Black does next day when follicle >4.0mm diameter was observed during the ovulatory wave in Autumn, for two days,while the control received vector only. Blood samples collected twice a day from the day follicle reaching >4.0mm diameter the the day on heat, and were analysed by radioimmunoassay for contentrations of FSH. The does in vector were allowed to be mated by fertile bucks during estrus. Ultrasonographic examations were performed transrectally to detected ovulatory follicle numbers and pregnancy on 28 days post-mating. Serum FSH concentrations were keep invariable or little increase in the experiment groups while the Serum FSH concentrations decreased in the group. Two or more follicles reaching >5.5mm in diameter and ovulation were obtained in the experiment groups, and 1.67±0.57 fetus were observed on 28 days post-mating. 151 Boer goats were superovulated to examine the factors affecting superovulation and embryo transfer (MOET). An optimal regime for superovulation treatment was identified as a 4-day treatment with decreasing dosages of 6-7 mg Chinese FSH or 240 mg Canadian FSH. The 4-day treatment with decreasing dosages of 6-7 mg Chinese FSH was, therefore, adopted to study effects of the age of does, season and repeated treatments on superovulation and embryo transfer. The best season for superovulation and embryo transfer and pregnancy was Autumn, and the best age range was 12-35 months old. No significant difference among the animals were found in the number of ovulations and the rate of transferable embryos between the first and the second superovulation. However, these parameters declined significantly for the third superovulation. No marked effects of the number of ovulations on the proportion of transferable embryos were noted. The parturition rate of the recipients receiving single embryos was not different significantly from those receiving two embryos, and the kidding rate calculated from embryos transferred did not differ significantly between recipients receiving one and two embryos.更多还原