摘要
旨在研究免疫血管活性肠肽(Vasoactive intestinal peptide,VIP)和抑制催乳素(Prolactin,PRL)分泌对鸡产蛋和就巢的影响机制。试验1:对18周龄未开产的泰和鸡,分别在试验d1、d28、d56和d84免疫含VIP羧基端15肽片段的VIP-BSA偶联蛋白,观察对产蛋和就巢的影响。试验2:利用刚开产的23周龄粤黄鸡,在试验d1、d23、d48、d73、d98免疫VIP串联四聚体重组蛋白,观察对产蛋和就巢的影响,并在第98天检测卵泡发育和下丘脑、垂体、F1～F3级LYF颗粒层和膜层相关基因的表达。试验1中免疫VIP组在开产后高峰期(d55～d61)的产蛋率显著低于对照组,但高峰后的(d89～d103)产蛋率显著高于对照组,同时免疫VIP组的就巢发生也要迟于对照组。试验2中,VIP免疫组的产蛋率在试验初高于对照组;在d33将光照从12h延长至16h后,2组的产蛋率均快速上升;产蛋高峰后,免疫组产蛋率快速下降并在d80～d105显著低于对照组。免疫VIP重组蛋白也降低了就巢的发生。2组鸡在d98的大黄卵泡、小黄卵泡和大白卵泡的数量无显著差异。免疫VIP重组蛋白并不影响下丘脑Gn-RH-Ⅰ和VIP、垂体LHβ和FSHβ的mRNA水平,但显著降低了垂体PRL的表达,也显著降低了垂体和下丘脑PRLR的表达。在检测的F1～F3卵泡组织中,免疫VIP重组蛋白也显著降低了F1和F3颗粒层的PRLRmRNA水平,降低了F1～F3颗粒层和膜层的LHR表达量,但对P450scc和StAR的表达量没有影响。两试验结果表明,免疫VIP能够降低PRL的表达和分泌,从而抑制产蛋引发的就巢发生,但是免疫VIP在抑制PRL表达分泌后也会抑制卵泡发育和产蛋,这一机制可能是通过影响卵泡组织LHR的表达而实现的。
This study was conducted to investigate the regulatory mechanisms of egg laying and development of incubation behaviour by immunization against vasoactive intestinal peptide（VIP） in hens.In experiment 1,18-wk old pre-lay Taihe pullets were immunized on d1,d28,d56 and d84 of the experiment,with VIP-BSA conjugate immunogen.In experiment 2,laying 23-wk old Yuehuang hens were immunized on d1,d23,d48,d73 and d98 of the experiment,with tethered 4VIP recombinant protein as immunogen.Tissues of hypothalamus,pituitary gland,theca and granulosa layers of F1 to F3 ovarian follicles were collected,in 10 immunized and 10 control hens after slaughter on d98.The results of experiment 1 showed that immunization against VIP significantly attenuat the pre-peak egg laying during d55 to d61 of the experiment 1,but significantly slowed post-peak decline of egg laying from d89 to d103 of the experiment.Meanwhile immunization against VIP also delayed the development of incubation behaviour.In experiment 2,the initial egg laying rate within 30 days after the experiment was low in both VIP-immunized and control hens,but was significantly higher in the former than that in the latter.Following increase of photoperiod from 12 h to 16 h,laying rate increased to the peak in both groups of hens.However VIP-immunized hens exhibited a substantial decrease in egg laying,which was significantly lower than that in the control group from d80 to d105 of the experiment.Percentage of hens incubating increased at a slower rate in the VIP-immunized hens than that in the control group,but were similar between the two groups at the end of the experiment.On d98 of the experiment,both groups of hens had similar numbers of large yellow,small yellow and large white follicles on the ovary.Immunization against VIP did not affect the mRNA expression level of GnRH-Ⅰ,VIP in the hyothalamus,nor affected LHβ and FSHβ in the pituitary gland.However,PRLRmRNA expression level in both hypothalamus and pituitary,and PRL expression level in the pituitary gland were all significantly lower in VIP-immunized hens.In addition,immunization against VIP decreased PRLR mRNA expression in granulosa cells of F1 and F3 follicles,and decreased LHR mRNA level in granulose and theca layers of F1-F3 follicles examined.Results of the 2 experiments demonstrated that immunization against VIP decreased gene expression and therefore secretion of PRL in the pituitary gland,which subsequently slowed development of incubation occuring after egg laying.Suppression of PRL secretion following VIP-immunization also depresses egg laying at certain stages,which may be a result of decreased LHR mRNA expression in the ovarian follicular cells.
出处
《畜牧兽医学报》
CAS
CSCD
北大核心
2011年第10期1470-1476,共7页
ACTA VETERINARIA ET ZOOTECHNICA SINICA
基金
国家自然科学基金(3067150430871795)
高等学校博士学科点专项科研基金(20050564001)
关键词
血管活性肠肽
催乳素
鸡
产蛋
就巢
vasoactive inteatinal peptide（VIP）
polactin（PRL）
chicken
laying
incubation
