不同产蛋阶段藏鸡与罗曼粉、海兰褐蛋鸡生殖系统解剖生理特性的比较研究

Comparative Study on Anatomical and Physiological Characteristics of Reproductive System of Tibetan Hens with Roman Pink and Hyline Brown Laying Hens at Different Laying Stages

为探究藏鸡与高产蛋鸡(罗曼粉、海兰褐)产蛋量差异的解剖生理学基础,在一个产蛋周期内对三种鸡血清促卵泡素(FSH)和雌激素(E_(2))值、输卵管发育解剖学及组织学的变化规律进行研究。按品种分3组,选用开产前期、开产期、产蛋高峰期、产蛋后期(分别为16、25、36、68周)的藏鸡、罗曼粉蛋鸡和海兰褐蛋鸡各80只,测定3种鸡不同时期血清FSH、E_(2)水平;在各周龄段随机取20只鸡,观察输卵管的发育情况及组织学特征。结果显示:①各组组间比较显示,在产蛋后期藏鸡组与海兰褐组血清FSH水平存在显著差异(P<0.05),其他时期藏鸡组与罗曼粉、海兰褐组FSH水平差异不显著(P>0.05);组内比较结果显示,3组鸡血清FSH水平在产蛋高峰期最高,与开产前期差异显著;3组鸡血清E_(2)水平组间比较显示在4个时期藏鸡血清E_(2)水平与罗曼粉、海兰褐蛋鸡存在显著差异(P<0.05),其中罗曼粉蛋鸡和海兰褐蛋鸡血清E_(2)水平差异不显著(P>0.05);组内比较显示,产蛋高峰期E_(2)水平最高,与开产前期和产蛋后期差异显著(P<0.05);②藏鸡组输卵管长度、重量与其他两组在不同产蛋阶段均有显著差异(P<0.05);组内比较结果显示,3组鸡产蛋高峰期输卵管的长度、重量指标均显著高于产蛋前期和产蛋后期(P<0.05);③藏鸡组在不同产蛋阶段输卵管各段黏膜皱襞高度、宽度指标(除开产前期峡部黏膜皱襞宽度外)均显著低于其他两组(P<0.05)。藏鸡生殖激素水平在不同产蛋阶段与高产的罗曼粉、海兰褐蛋鸡均存在差异,进而造成了藏鸡与其他两种蛋鸡在解剖学、组织学上的差异。生殖激素及输卵管的发育与鸡的产蛋性能密切相关,因此要提高藏鸡的产蛋性能和繁殖性能,需要进一步找到调控藏鸡生殖激素分泌的体内外因素。

In order to investigate the anatomical and physiological basis of the difference in egg produc⁃tion between Tibetan chickens and high laying hens(Romain pink and Hyline brown),the chang⁃ing patterns of serum Follicle-stimulating hor⁃mone(FSH)and estrogen(E_(2))values,oviduct de⁃velopment anatomy and histology of the three spe⁃cies of chickens were investigated during an egg-laying cycle,which provided theoretical bases for further understanding and development of egg-laying performance and reproductive performance of Tibetan chickens.Three groups were divided according to breeds,and 80 birds each of Tibetan chick⁃ens,Romain pinks and Hyline browns were selected in the pre-laying period,laying period,peak laying period and post-laying period(16,25,36 and 68 weeks,respectively),and the levels of serum FSH and E_(2)hormones of the three kinds of chickens were measured at different periods of time;20 chickens were randomly selected at each weekly age section,and the development of the oviducts and the histological characteristics were observed.The results showed that:①inter-group comparison showed that there was a significant difference between the serum FSH levels of Tibetan chickens and Hyline Brown group at the late stage of egg laying(P<0.05),while the difference between them and the FSH levels of Romaine Pink and Hyline Brown at other periods was not significant(P>0.05);intra-group comparison showed that the serum FSH levels of chickens of the three groups were highest in the peak period of egg laying,and the difference with that of the early stage of egg laying was significant;serum E_(2)levels of the three groups of chickens showed that there was a significant difference in the peak period of egg laying,and the difference was significant;and the difference between them was significant.levels between groups showed that in the four periods of Tibetan chickens serum E_(2)levels differed significantly(P<0.05)from those of Roman pink and Hyline brown hens,where the differences in serum E_(2)levels between Roman pink and Hyline brown hens were not significant(P>0.05);within-group comparisons showed that E_(2)lev⁃els were highest in the peak laying period,and the differences with the pre-laying period and the late laying period were significant(P<0.05);②Tibetan chickens′oviduct lengths,weight were significantly different from those of the other two groups at different egg-laying stages(P<0.05);intra-group compari⁃son showed that the length and weight of oviducts in the peak egg-laying period of the three groups of chickens were significantly higher than those in the pre-laying period and the post-laying period(P<0.05);③the mucosal folds of oviducts of Tibetan chickens were significantly lower than those of the other two groups in the various laying stages in terms of mucosal folds′heights and widths(except for the width of mucosal folds of isthmus at the pre-laying period)(P<0.05).Reproductive hormone levels of Ti⁃betan chickens differed from those of high-yielding Roman Pink and Hyline Brown hens at different egg laying stages,which in turn caused anatomical and histological differences between Tibetan chickens and the other two types of laying hens.The development of reproductive hormones and oviducts is closely re⁃lated to the egg-laying performance of chickens,therefore,to improve the egg-laying performance and re⁃productive performance of Tibetan chickens,it is necessary to further find the exogenous and exogenous factors that regulate the secretion of reproductive hormones in Tibetan chickens.