【作者】 张静；

【导师】 马保华； 李延华；

【作者基本信息】 西北农林科技大学 ， 兽医硕士（专业学位）， 2017， 硕士

【摘要】 奶山羊在我国的饲养历史悠久,而且山羊奶营养成分均衡合理,富含蛋白质、糖类、钙和多种维生素,容易被人体消化吸收,能够弥补人的膳食营养不足,因而羊奶具有较好的营养保健作用,尤其适合孕妇,老人和小孩食用。近年来山羊奶逐渐在我国的乳品消费市场占有一席之地,并凸显出一定的市场优势。但是为人类提供优质乳品来源的奶山羊为典型的短日照季节性繁殖动物,这种季节性繁殖模式导致一个相对固定的产羔/产奶周期,其中只有7~8个月左右的时间能够向市场提供鲜羊奶,奶山羊产奶时期的不均衡导致了消费市场鲜羊奶供应的年度不均衡性。由于奶山羊生产中的这种限制,给人们全年饮用鲜羊奶带来了许多困难,也在一定程度上限制了奶山羊养殖及其产业发展。国内外已有许多科研人员在奶山羊均衡产奶方面进行了部分研究或提出了解决方案,但大多并未真正在生实践中开展应用研究或推广实施。因此,如何满足山羊奶的市场年度均衡需求,向市场全年均衡供应鲜羊奶,是奶山羊生产实践中急需解决的问题,它不仅关乎养殖户的利益,也对山羊奶市场的发展起着至关重要的作用。本试验根据实施地点山羊奶消费市场的调查,近两年的山羊奶鲜奶订奶户冬季相对较多、夏季相对减少,而按照传统奶山羊产羔/产奶周期,恰好与这种市场需求规律相矛盾。本试验在课题组前期2年奶山羊全年均衡产奶生产计划制定与实施的基础上,在本试验年度根据这种山羊奶的地方性市场需求规律,调整全年奶山羊繁殖生产和鲜奶供应计划,使奶山羊场的年度产羔/产奶周期尽量满足这种市场规律。同时,对奶山羊全年均衡供奶技术体系的相关配套技术进行试验研究,包括奶山羊精液稀释液的优化、不同月份产羔母羊泌乳期外周血5种生殖激素和生长激素的监测,以及不同月份产羔母羊泌乳规律监测。试验工作将为制定适于奶山羊全年均衡供奶生产计划的繁殖计划及采取现代繁殖技术、饲养管理、饲草供应等生产环节,保证奶山羊场的全年均衡供奶,并能够广泛地推广应用于生产实践,具有重要的指导意义。奶山羊场全年均衡供奶生产应用试验结果如下:1.根据生产应用试验当地市场山羊奶鲜奶的季节性需求规律,于2016年8月~9月、2017年1月和3月对试验场适繁母羊分批进行同期发情或诱导发情处理,经产泌乳后期母羊采用炔诺酮阴道缓慢释放装置+孕马血清促性腺激素/促卵泡素+前列腺素(norethisterone vaginal slow release device+pregnant mare serum gonadotropin/follicle-stimulating hormone+prostaglandin,NRID+PMSG/FSH+PG)处理法进行同期发情处理,三个批次的母羊从撤除NRID开始96 h内发情率分别为97.5%,95.23%和93.23%;青年母羊采用一次或两次PG+PMSG/FSH法进行同期发情处理,发情率分别为92.3%,92.59%和90%;经产羊和青年羊采用的处理方法同期发情效率差异不显著(P>0.05)。发情羊采用人工授精或本交方式配种,返情羊本交复配。2016年9月配种母羊妊娠率为84.28%,2017年1月配种母羊妊娠率为81.96%。2.在课题组前期精液低温保存稀释液筛选试验的基础上,对初步筛选的四个精液稀释液配方,在严格对照条件下进行了精液保存时间的进一步筛选,并对最终筛选的两个精液稀释液配方进行了卵黄添加比例的优化。首先在四种初步筛选的配方中添加10%的新鲜卵黄组成精液稀释液,对精液进行10倍稀释、低温保存,其中配方B配方D低温保存精液的活力和质膜完整性显著优于配方A和配方C(p<0.05)。在此基础上,在配方B和配方D中分别添加5%、7.5%、10%、12.5%、15%、17.5%和20%卵黄组成不同卵黄添加比例的精液稀释液,对精液进行10倍稀释、低温保存。其中添加10%、12.5%和15%卵黄的稀释液配方B和配方D保存的精液,其精子活力和质膜完整性指标显著优于其他几种卵黄比例(p<0.05),且三种卵黄添加比例之间差异不显著(P>0.05),说明适宜的卵黄添加比例区间为10%~15%。在卵黄添加比例为10%、12.5%和15%时,配方B和配方D在96 h内低温保存精液的活力和质膜完整性无差异(P>0.05),96 h之后配方D优于配方B(p<0.05)。3.采集2015~2016生产年度不同批次配种母羊泌乳期外周血并分离血清,利用酶联免疫吸附法检测血清中5种生殖激素和生长激素浓度。结果表明,不同批次配种母羊产后泌乳期生殖激素和生长素水平变化曲线一致。其中产羔第0天、产羔后第7天、第1个月~第8个月检测的血清中催乳素(prolactin,PRL)浓度从产羔第0天起开始升高,产后第7天达到一个较高水平,随后逐渐降低;促卵泡素(follicle stimulating hormone,FSH)从产后0天开始升高,到产后第7天达到一个较高水平,随后下降,至产羔第1个月后保持在一定浓度范围内变化;促黄体素(luteinizing hormone,LH)从产后0天开始下降,在产后第2个月达到一个高浓度,随后逐渐下降;雌二醇(estradiol,E2)从产后0天开始下降,从产后第7天开始在一定浓度范围内缓慢上升,到产后第8个月达一个较高浓度水平;孕激素(progesterone,P4)于产羔当天开始下降至第7天后缓慢升高,至产后第2个月时达到较高值,随后缓慢降低;生长激素(growth hormone,GH)在产羔当天达到较高值,随后下降并在产后第7天降至较低水平,随后在一定浓度范围内变化。4.利用2016生产年度不同月份产羔母羊,进行整个泌乳期泌乳曲线监测。结果表明,通过记录并统计分析产后13~17天、43~47天、73~77天、103~107天、133~137天、163~167天和193~197天的泌乳量数据制作的泌乳曲线发现,不同月份产羔母羊泌乳曲线变化趋势基本一致,但不同月份产羔母羊泌乳量差异较大(p<0.05),1月份产羔母羊泌乳量较高,5月份产羔母羊泌乳量较低。分析原因主要可能与不同批次泌乳母羊年龄、胎次、全年不同月份饲料供应、气温变化等因素有关。更多还原

【Abstract】 Dairy goat has a long history of feeding in our country,because the goat milk nutrition balanced and reasonable,rich in protein、carbohydrates、calcium and vitamins,easy to digest and absorb for human body,and make up for people’s dietary deficiencies,better nutrition and health effects,especially for pregnant women,the elderly and children eating.In recent years,goat milk gradually occupies a place in our country’s dairy consumer market,and highlights a certain market advantage.Dairy goats providing people for the good quality of goat milk,But dairy goats for the typical short-day seasonal breeding of animals,this seasonal breeding model led to a relatively fixed lambing/milk production cycle,only 7 to 8 months to the market provide fresh goat milk,dairy goat milk production period of uneven imbalance led to the consumption of fresh milk supply market annual imbalance.Due to this restriction in the production of dairy goats,it has brought many difficulties to drinking fresh goat’s milk throughout the year,to a certain extent also limited the development of dairy goat farming and goat’s milk industry.Many researchers at home and abroad have carried out some research on the balanced milk production of dairy goats and put forward some proposed solutions,but most of them have not really applied in practice.Therefore,How to ensure that the annual market demand for goat milk,to the market a balanced supply of fresh milk throughout the year,dairy goat production practice in urgent need to solve the problem,it is not only about the interests of farmers,but also on the development of goat milk market plays a vital role.According to the implementation of the application of experimental production site goat milk consumer market survey,nearly two years of goat milk orders relative more in winter,the relative reduction in summer,and in accordance with the traditional dairy goat fixed lambing/milk production cycle try to meet this market changes laws.This test is based on task group’s dairy goat annual balanced milk production plan in the last 2 years,in the year of production and application test,adjust the annual dairy goat reproductive plan to make the dairy goat milk production,try to meet this market changes in the law.In the year of balanced production of milk production test.At the same time study the dairy goat annual balanced supply of milk matching technology system,including dairy goat semen extendersoptimization,monitoring of 5 reproductive hormones and growth hormones in peripheral blood of lambs of lambs in different months,as well as monitoring lactation laws in different seasons lambing lactation curve.In order to develop a breeding plan for the annual balanced milk production for dairy goats and to adopt modern breeding techniques,feeding and management,forage supply and other production links to ensure the annual balanced supply of dairy goats,and can be widely promoted applied to the production practice,has important guiding significance.Dairy goat farm annual balanced supply of milk production test results are as follows:1.According to the test site of the local market goat milk seasonal demand regular laws,This test for the experimental site breeds ewes in August to September 2016,January and March 2017 conducted synchronization estrus or induced estrus treatment,the production of lactating ewes using norethisterone vaginal slow release device + pregnant horse serum gonadotropin(NRID + PMSG/FSH + PG)method to conducted synchronization estrus or induced estrus treatment.The estrus rates of the three batches of ewes were 97.5 %,95.23 %and 93.23 % respectively within 96 h after removal of NRID.The young ewes were treated with one or two PG + PMSG/FSH methods conducted,The estrus rates of the three batches of ewes were 92.3 %,92.59 % and 90 % respectively.There was no significant difference in the efficiency of the treatment between pluriparous ewes and young ewes(P>0.05).Estrus ewes use artificial insemination or mate with ram,returning ewes use ram mate.In September 2016,the pregnancy rate of pregnant ewes was 84.28 %,and in January 2017,the pregnancy rate of pregnant ewes was 81.96 %.2.Based on the research group’s test on the semen cryogenic preservation extender screening of dairy goat semen,for the elected four semen extender formulas were preliminary screened and then the semen preservation time was further screened under strict control conditions in the earlier stage.At the first,we added 10 % of the fresh egg yolk in the four kinds of semen extender,the semen 10 times dilution,cryogenic preservation,the test results show that the formula B and formula D cryogenic preservation sperm motility and plasma membrane integrity was significantly better than formula A and formula C(p<0.05).On the basis of this,5 %,7.5 %,10 %,12.5 %,15 %,17.5 % and 20 % of the yolk were added to the semen dilution of different yolk ratios in formula B and formula D,the semen 10 times dilution,cryogenic preservation.The results showed that the sperm motility and plasma membrane integrity of the semen preserved in formula B and formula D of 10 %,12.5 % and15 % of the egg yolk were significantly better than those of several other yolk ratios(p<0.05),and the three ratios have no difference(P>0.05).So we elected the suitable interval for addition of yolk concentration in this experiment is 10 % to 15 %.By comparing the effectsof adding 10 %,12.5 % and 15 % yolk in the formula B and formula D cryogenic preservation of semen,the results showed that there was no difference in the effect of cryogenic preservation of semen in the two formulas during 96 h(P > 0.05),there had significant difference between the two groups after 96h(P < 0.05).3.The peripheral blood of ewes lambing in different months breeding in the year2015~2016 was collected and the serum was isolated.used enzyme linked lmmunosorbent assay method to detected the serum level of five reproductive hormones and growth hormone.The results showed that the changes curve five reproductive hormones and growth hormone levels of ewes lambing in different months breeding were consistent.The concentration of prolactin(PRL)in the serum detected on day 0,day 1 and month 8 of lambing was increased from day 0 of lambing,and postpartum day 7 reaching a higher concentration level,and then gradually decreasing;Follicle stimulating hormone(FSH)increased from 0 days after delivery to the postpartum 7 days to reach a higher concentration level,and then decreased to the lambs after first month to maintain a certain concentration within the change;Luteinizing hormone(LH)decreased from 0 days after delivery,reached a high concentration in the second month after delivery,and then gradually decreased;Estradiol(E2)began to decline from 0 days after delivery,from the first 7 days after birth in a certain concentration range slowly increased to the first 8 months after delivery to a higher concentration level;Progesterone(P4)began to decline on the day of lambing to 7 days after the slow rise to the second month after delivery to reach a higher value,and then slowly reduced;Growth hormone(GH)reached the higher level on the day of lambing,then decreased and decreased to a low level on day 7 postpartum,followed by a fluctuating range.4.Used the ewes lambing in different months in 2016 and monitored the entire lactation lactation curve.The results showed that lactation was produced by recording and statistical analysis of lactation data from 13 d to 17 d,43d to 47 d,73d to 77 d,103d to 107 d,133d to 137 d,163d to 167 d,193d to 197 d.The results showed that the lactation curve of lambs of different lambing in different months was basically the same,but the difference of lactation volume was significant(p<0.05),The lactation volume of the ewes lambing in January were higher,but in May was lower.The main factors of analysis may be related to the age and parity of ewes lambing in different months lactation,feed supply and the variation of temperature in different months of the year.更多还原