【作者】 和希顺；

【导师】 何瑞国； 熊远著；

【作者基本信息】 华中农业大学 ， 动物遗传育种与繁殖， 2008， 博士

【摘要】 与鸡和鸭相比,鹅的繁殖力较低,提高鹅的繁殖性能对促进养鹅业发展具有重要意义。动物下丘脑分泌的促性腺激素释放激素（gonadotropin releasing hormone,GnRH）能通过作用于垂体前叶的GnRH受体调节促卵泡素（follicle stimulatinghomone,FSH）和促黄体素（luteinizing hormone,LH）的分泌来调节配子的形成及类固醇类激素的产生,是动物生殖过程中最重要的激素之一。目前人工合成的GnRH类似物（GnRH-a）已超过2000多种。大量的研究表明,经过修饰,人工合成的GnRa-a半衰期长,与受体结合能力强,比天然GnRH稳定性更强、活性更高,能提高家畜或家禽的繁殖性能,但关于GnRH-a对鹅繁殖性能影响的研究报道较少。实际生产中应用GnRH-a主要是通过注射方式给药,不仅劳动强度大,而且动物应激反应强烈,影响效果。本文首先通过单因素试验设计来筛选溆浦鹅种鹅产蛋期日粮中适宜的蛋白水平;然后在日粮适宜的蛋白水平下,通过比较研究注射和口服GnRH-a（LHRH-A₃）对溆浦鹅种鹅产蛋性能、蛋品质、种蛋孵化、生殖内分泌及卵泡发育机制的影响,探讨提高溆浦鹅种鹅繁殖性能的GnRH-a（LHRH-A₃）口服用药方式的可行性和适宜剂量。试验结果分别摘要如下:1日粮不同蛋白质水平对溆浦鹅种鹅产蛋性能、蛋品质和种蛋孵化的影响目的:确定溆浦鹅种鹅产蛋期糙米型日粮适宜蛋白水平。方法:采用单因子试验设计,设计五种等能日粮饲喂溆浦鹅种鹅,日粮蛋白质水平分别为13.0%、14.5%、16.0%、17.5%和19.0%,测定各组产蛋性能、蛋品质和种蛋孵化指标及血清生化指标和生殖内分泌激素变化。结果:（1）日粮水平达到16.0%时,产蛋率、日平均产蛋量显著增加（P＜0.05）,料蛋比显著降低（P＜0.05）,料蛋比与产蛋率和产蛋量二次曲线回归显著（P＜0.05）;（2）日粮蛋白质水平对蛋品质和受精率无显著影响,但13.0%的蛋白质水平组,种蛋孵化率和健雏率显著降低（P＜0.05）;（3） 19.0%蛋白质水平组,鹅血清尿酸的浓度显著升高（P＜0.05）;（4） 16.0%、17.5%和19.0%的蛋白质水平组,血清孕酮和雌二醇的浓度显著升高（P＜0.05）,催乳素无显著变化。结论:溆浦鹅种鹅产蛋期糙米型日粮蛋白质适宜水平为16.0%。2口服和注射促排三号（LHRH-A₃）对溆浦鹅种鹅产蛋性能、蛋品质和种蛋孵化的影响目的:研究溆浦鹅种鹅口服LHRH-A₃给药方式的可行性。方法:试验设七个处理组,第Ⅰ、Ⅱ、Ⅲ组每只鹅分别注射剂量为5μg/羽、10μg/羽和15μg/羽的LHRH-A₃,第Ⅳ、Ⅴ、Ⅵ组分别将5μg/羽、10μg/羽和15μg/羽的LHRH-A₃随饲料拌喂,Ⅶ组为对照组,测定各组产蛋性能、蛋品质及孵化等相关指标。结果:（1）口服和注射LHRH-A₃,料蛋比均显著降低（P＜0.05）,产蛋率有增加的趋势,其中口服剂量为10μg/羽时,产蛋率显著提高（P＜0.05）;（2）口服和注射LHRH-A₃,鹅平均蛋重、蛋形指数、蛋黄比例、蛋白比例、蛋壳比例及蛋壳厚度等指标差异不显著,但注射5μg/羽和15μg/羽LHRH-A₃,破畸蛋率显著升高;（3）口服和注射LHRH-A₃,种蛋受精率和孵化率无显著差异,但口服组的健雏率有上升的趋势。结论:溆浦鹅拌料口服LHRH-A₃是可行的,口服剂量为10μg/羽时,其产蛋率最高。3口服促排三号（LHRH-A₃）对溆浦鹅种鹅产蛋性能、蛋品质、种蛋孵化、生殖内分泌和卵泡发育调节机制的研究目的:探讨口服LHRH-A₃对溆浦鹅种鹅产蛋性能、蛋品质、种蛋孵化、生殖内分泌和卵泡发育调节机制,进一步验证口服LHRH-A₃的适宜剂量。方法:采用单因子试验设计,分别饲喂0μg/羽、5μg/羽、10μg/羽、15μg/羽和20μg/羽的LHRH-A₃,测定各组溆浦鹅的产蛋性能指标、蛋品质相关指标、孵化指标、血清生化指标、血常规部分指标、血清部分生殖激素水平、卵巢颗粒细胞凋亡及屠宰性能。结果:（1）与对照组相比,10μg/羽和15μg/羽组,溆浦鹅的产蛋率显著提高,20μg/羽组产蛋率显著降低,5μg/羽、10μg/羽、15μg/羽组料蛋比显著降低,20μg/羽组料蛋比显著升高（P＜0.05）;（2）各组平均蛋重、蛋品质、受精率、孵化率和健雏率差异不显著;（3）各组鹅血常规和血清生化指标差异不显著;（4） 10μg/羽和15μg/羽组,血清孕酮和雌二醇的浓度显著升高,20μg/羽组,孕酮显著下降（P＜0.05）;各组的催乳素浓度差异不显著;（5） 20μg/羽组,卵泡颗粒细胞的凋亡率显著升高（P＜0.05）;（8）各组鹅全净膛重和全净膛率差异不显著,但15μg/羽组的卵巢重显著升高,20μg/羽的组的卵巢重显著降低（P＜0.05）。结论:鹅口服LHRH-A₃剂量为10μg/羽和15μg/羽时,能促进孕酮和雌二醇分泌,产蛋率显著提高;口服剂量为15μg/羽时,能促时鹅卵泡发育和卵巢生长;口服剂量为20μg/羽时,卵泡颗粒细胞的凋亡率显著升高,抑制卵泡发育和卵巢生长;溆浦鹅LHRH-A₃适宜口服剂量为10μg/羽。4饲喂促排三号（LHRH-A₃）对延长溆浦鹅种鹅产蛋期调节机制的研究目的:探讨LHRH-A₃对产蛋后期溆浦鹅种鹅产蛋性能、蛋品质、种蛋孵化、卵巢和生殖内分泌的调节机制。方法:采用单因子梯度试验设计,分别饲喂剂量为0μg/羽（对照组）、10μg/羽和15μg/羽的LHRH-A₃,测定各组每周的产蛋性能、蛋品质、种蛋孵化指标及血清部分生殖激素和卵巢重量。结果:（1） 10μg/羽和15μg/羽组的产蛋率均较对照组下降缓慢,15μg/羽组鹅产蛋率显著高于对照组（P＜0.05）;（2）各组的平均蛋重差异不显著;（3） 10μg/羽和15μg/羽组LHRH-A₃处理组卵巢重显著高于对照组;（4） 10μg/羽LHRH-A₃组的孕酮浓度和催乳素浓度显著低于对照组（P＜0.05）。结论:口服10μg/羽LHRH-A₃通过促进卵巢生长发育及抑制孕酮和催乳素分泌来维持溆浦鹅产蛋后期产蛋性能,从而延长产蛋周期,提高产蛋率。更多还原

【Abstract】 Because of the lower reproductivity compared to chicken and ducks,it is necessary to improve the reproductive performance of geese in geese breeding and feeding. Gonadotropin-releasing hormone（GnRH）,the central initiator of the reproductive hormonal cascade,is secreted from hypothalami and stimulates the biosynthesis and secretion of LH and FSH from pituitary gonadotropes.Over 2000 analogues of GnRH have been developed and tested over the last 30 years.With its stabler nature and higher receptor affinity,the synthetic GnRH analogues（GnRH-a） have achieved widespread clinical use for the control of reproduction in animals.Due to the ususal injection administration results severe stress on animals,this investigation was designed to study（1） the optimal protein levels in diets of Xupu breeder geese during its laying period,（2） the effect of oral administration of GnRH-a（LHRH-A₃） on egg production,egg quality,egg incubation,reproductive endocrine and folliculogenesis of Xupu breeder geese.This would shed light on possibility that oral administration of GnRH-a with optimal might improve the reproductive performance in geese.1 Laying,egg quality and hatchability in response to protein levels of diets in Xupu Breeder GeeseObjective:to study the optimal protein level of brown rice based-diets of Xupu Breeder Geese during laying period.Methods:using singular factor design,after feeding 5 kinds of brown rice based-diets with 13.0%,14.5%,16.0%,17.5%and 19.0%,egg production,egg quality and hatchability,parameters of serum biochemistry and reproductive hormone in different treatments were measured and determined,respectively. Results:（1） With the significant regression of two factors of feed conversion efficiency between the rate of laying and egg production,the rate of laying and egg production increased significantly,while the feed conversion efficiency decreased significantly.（2） There were no differences in egg quality and fertilization rate among all treatments. However,the egg hatchability and percent of healthy gosling decreased significantly in 13.0%treatment.（3） Uric acid in serum of geese increased significantly in 19%treatment. （4） concentration of P₄ and E₂ increased significantly in 16.0%、17.5%and 19.0% treatment.Conclusion:the optimal protein level of brown rice based-diets of Xupu Breeder Geese is 16.0%.2 Laying,egg quality and hatchability in response to oral and injection administration of LHRH-A₃Objective:to study the possibility of oral administration of LHRH-A₃ in geese. Methods:Birds were injected 5,10 and 15μg/bird of LHRH-A₃ in treatmentⅠ,Ⅱ,Ⅲ, respectively.Meanwhile,the other birds were oral administrated with 0,5,10 and 15μg/bird of LHRH-A₃ in treatmentⅣ,Ⅴ,Ⅵ,Ⅶ,respectively,and the egg production,egg quality and hatchability of geese in all of the 7 treatments was measured during the whole experiment.Results:Compared to control treatment,feed conversion efficiency decreased significantly and the tendency of eggs production increased in oral and injection treatments.Moreover,the eggs production increased significantly in 10μg/bird treatment. （3） there were no differences in egg quality,fertilization rate,hatchability and percent of healthy gosling in response to oral administration of LHRH-A₃.However,percent of healthy gosling was decreased in treatment of injection administration（p＞0.05）.Conclusion:Oral administration of LHRH-A₃（mixed with feed） was a kind of better treatments in geese feeding compared to injection and egg production of geese was the highest in 10μg treatment.3 Laying,egg quality,hatchability,reproductive incretion and folliculogenesis in response to oral administration of LHRH-A₃Objective:To investigate the regulative mechanism of oral administration of LHRH-A₃ on laying performance,egg quality,hatchability,reproductive incretion and folliculogenesis of breeding geese.Methods:A feeding trial was carried out and lasted for 60 d according to a singular factor design.Birds were oral administrated with 0,5,10,15 and 20μg/bird of LHRH-A₃ every day,respectively.At the end of the feeding trial,the egg production,egg quality,hatchability,parameters of serum biochemistry and blood routine, reproductive hormone,apoptosis of granulose cell and slaughter performance of geese in all treatments were measured.Results:（1） Compared to control treatment,the laying rate increased significantly（P＜0.05） in 10μg/bird and 15μg/bird treatments,however decreased in 20μg/bird treatment.Feed conversion efficiency decreased significantly （P＜0.05） as LHRH-A₃ increased from 0 to 15μg/bird but increased at 20μg/bird.（2） No significantly（P＞0.05） difference was observed in egg weight,egg quality,fertilization rate,the egg hatchability and percent of healthy gosling among all treatments.（3） There were no differences in parameters of serum biochemistry and blood routine in response to oral administration of LHRH-A₃.（4） The serum contents of P₄ and E₂ in 10μg/bird and 15μg/bird treatments were significantly（P＜0.05） higher than that in the control.However, the P₄ content decreased significantly（P＜0.05） in 20μg/bird treatment.No significant difference in PRL content was observed.（5） The rate of apoptosis of granulose cell in 20μg/bird treatment was significantly（P＞0.05） higher than that in other group.（6） The eviscerated weight and percentage of eviscerated yield showed no significant difference in all treatments.However,the ovary weight was highest（P＜0.05） in 15μg/bird treatment and lowest（P＜0.05） in 20μg/bird treatment.Conclusion:The secretion of P₄ and E₂ can be improved by oral administration of 10 and 15ug/bird LHRH-A₃（mixed with feed）. Meanwhile,the folliculogenesis and ovary growth can be promoted by oral administration of 15ug/bird LHRH-A₃.However,oral administration of 20ug/bird LHRH-A₃ would increase the rate of apoptosis of granulose cell and inhibit the folliculogenesis and ovary growth.The optimal oral administration dosage of LHRH-A₃ was 10ug/bird.4 The regulation mechanism of LHRH-A₃ oral administration on laying period extensionObjective:To investigate the regulative mechanism of oral administration of LHRH-A₃ on laying performance,egg quality,hatchability,reproductive incretion of breeding geese during the late stage of egg production cycle.Methods:A feeding trial was carried out and lasted for 30 d according to a singular factor design.Birds during the late stage of egg production cycle were oral administrated with 0,10 and 15μg/bird of LHRH-A₃ every day,respectively.During the whole period of the feeding trial,the egg production,egg quality,hatchability,reproductive hormone and ovary weight of geese in all treatments were measured every week.Results:（1） Compared to control treatment,the laying rate in 15μg/bird treatment was significantly（P＜0.05） higher,and the reducing speed of laying rate was slower in 15μg/bird and 10μg/bird treatments.（2） No significantly（P＞0.05） difference was observed in average egg weight among all treatments.（3） The ovary weight was significantly（P＜0.05） higher in 10μg/bird and 15μg/bird LHRH-A₃ treatment than that in the control.（4） The serum contents of P₄ and E2 in 10μg/bird treatment were significantly（P＜0.05） higher than that in the control. However,the serum P₄ and PRL contents in 10μg/bird treatment was significantly （P＜0.05） lower than that\in the control.Conclusion:The ovary growth of breeding geese during the late stage of egg production cycle could be promoted and the secretion of P₄ and PRL could be inhibited by oral administration of 10 ug/bird LHRH-A₃.Thus,the laying rate could be promoted and the laying period could be extended.更多还原