摘要
【目的】为了探讨慢羽系中杂合子公鸡基因分型准确率和构建无ev21基因抗病品系,探讨育种群中慢羽公鸡基因分型、慢羽中的微长型(L1)、倒长型(L2)、等长型(L3)、未出型(L4)4种表型以及与生产性能关系。另外,通过表达量的差异甄别快慢羽候选基因催乳素受体基因(PRLR)和精子鞭毛蛋白2(SPEF2)的可行性。【方法】采用PCR-RFLP对清远麻慢羽公鸡进行分子分型,通过后裔测定的测交方法验证其分子分型的准确性,运用方差分析对各组别进行检验,采用百分数资料的t检验法比较各基因分型组别间对生产性能影响;利用RT-PCR对快慢羽的候选基因进行定量分析,重点比较了快羽中的R2型与慢羽中的L2型和L4型的定量差异。【结果】568只慢羽公鸡中,缺失体组(ev21^-)占比41.73%,ev21^+组占比为58.27%,其中纯合子与杂合子分别占比为8.80%和49.47%;经测交验证79只公鸡后代,慢羽纯合子和缺失体基因分型准确率为46.83%,基因分型杂合子实质为纯合子。慢羽公鸡中ev21^+组其后代的等长型比率显著高于ev21^-组(P≤0.05),ev21-组公鸡的105日龄的通管性能极显著高于ev21^+组(P≤0.01)。一日龄的鸡,在R2对慢羽(L2+L4)中PRLR表达差异不显著(P>0.05),但其表达量在R2与L4型对比中则下调,达到显著水平(0.01<P≤0.05),而SPEF2在慢羽中表达均极显著高于快羽鸡(P≤0.01),其中与快羽R2型比较,SPEF2分别在未出型(L4)及倒长型(L2)中均上调表达,差异均达极显著水平(P≤0.01)。【结论】研究尚需探索出慢羽杂合子准确率高的基因分型新方法,慢羽杂合子公鸡判别目前离不开现场测交验证;可以组建无ev21基因抗病品系;需进一步探讨造成ev21^+组与ev21^-组别间等长型比率以及羽毛成熟性差异的原因;一日龄的SPEF2与PRLR均为影响快慢羽表型不同亚型差异的候选基因。
【Objective】In order to verify the genotyping accuracy of heterozygotic cocks,and to construct the resistant strain without ev21 gene,the relationship among genotypes,four late-feathering sub-phenotypes(named micro-type as L1,inverted type as L2,isometric type as L3,and ungrown type as L4)and the production performance were investigated in the late-feathering Qingyuan partridge cocks.The feasibility was demonstrated by the expression profile difference of two candidate genes,i.e.,Prolactin Receptor(PRLR)and Sperm Flagellar Protein 2(SPEF2),between the early-and late-feathering Qingyuan partridge cocks.【Method】Genotypes were detected by PCR-RFLP in the late-feathering Qingyuan partridge cocks,and its accuracy was verified by progeny testing using a test cross.The production differences among genotyping groups were compared by variance analysis of percentage data and t-test.The expressions of two candidate genes were quantified by real-time quantitative PCR(RT-PCR)in both the early(R^2)feathering and late(L2 and L4)feathering cocks.【Result】Among the 568 late-feathering cocks,the proportion of the deletant group(ev21^- group)was 41.73%,and that of the ev21^+ group was 58.27%,of which the homozygotes and the heterozygote accounted for 8.80% and 49.47%,respectively.By the test cross,the genotyping accuracy was 46.83%both in the homozygote group and the deletant group,indicating that the heterozygote was in fact homozygote.The descendant percentage of the isometric late-feathering type in ev21^+ group was significantly higher than that in ev21^- group(P≤0.05).The feather maturity of the late-feathering cocks at 105-day-old in the ev21^- group was extremely significantly higher than that in ev21^+ group(P≤0.01).At one-day-old chicks,the expression of PRLR gene between R2 versus(L2+L4)showed no any difference(P>0.05),but its expression between R2 versus L4 was significantly down-regulated(0.01<P≤0.05).While the expression of SPEF2 gene in late-feathering chickens was extremely significantly higher than that in early-feathering chickens(P≤0.01).By comparing with the R2 group,SPEF2 significantly differentially up-regulated in the L4 and L2 groups(P≤0.01).【Conclusion】New genotyping method should be developed for improving the accuracy of the heterozygote in the late feathering cocks.Up to now,a test cross is essential for the chicken production.Construction of the ev21^- resistant strain is viable in late-feathering chicken breeding.Furthermore,studies need to be conducted to figure out the difference of isometric subtype ratio and feather maturity between the ev21^+ group and the ev21^- group.Besides,SPEF2 and PRLR were candidate genes for subtypes affecting the difference of early-feathering and late-feathering chickens at 1-day-old.
作者
李华
方桂军
华国洪
谭淑雯
张正芬
洪煜宇
于辉
LI Hua;FANG GuiJun;HUA GuoHong;TAN ShuWen;ZHANG ZhengFen;HONG YuYu;YU Hui(Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding/Foshan University,Foshan 528225,Guangdong;Guangdong Tinoo’s Foods Corporation Ltd.,Qingyuan 511827,Guangdong)
出处
《中国农业科学》
CAS
CSCD
北大核心
2020年第9期1913-1920,共8页
Scientia Agricultura Sinica
基金
国家科技支撑计划(2015BAD03B00)
广东省科技项目(2016B020233007,2017-1649)
广东省动物分子设计与精准育种重点实验室(2019B030301010)
清远市产学研合作项目(2018B02)。
关键词
清远麻公鸡
慢羽
基因分型
生产性能
Qingyuan partridge cocks
late-feathering
genotyping
performance