摘要
[目的]为了解北京鸭(P)、金陵白鸭(J,品系)及正反交后代(PJ、JP)出生后生长速度和肌纤维特性的差异,测定0~7周龄体重,用非线性回归模型探求4个群体鸭生长规律;采集7周龄公鸭胸肌组织,比较肌纤维特性和相关基因表达水平。[方法]利用Logistic、Gompertz非线性模型拟合生长曲线,通过拟合度(R^(2))和残差平方和(E)选择最适模型,计算相对生长率、绝对生长率及其杂交一代(F_(1))的杂种优势率;利用肌纤维组织切片和Image pro plus软件分析比较肌纤维特性;利用RT-qPCR技术检测肌肉发育相关基因表达水平。[结果]P、PJ和JP组选择Logistic模型,J组选择Gompertz模型为最适模型(R^(2)≥0.986,E≤751.49);4周为拐点周龄,且P组质量最大,J组最小;各组相对生长率接近,绝对生长率差异明显,JP组4周龄的绝对生长率具有明显杂种优势,PJ组在6周后表现出优势。不同品种鸭的7周龄肌纤维直径、横截面积和密度均差异极显著(P<0.01);每个基因在F_(1)的表达水平介于亲本之间且P组最高,P与J组差异极显著(P<0.01)。此外,F_(1)的生肌决定因子(Myf 5)表达与亲本差异极显著(P<0.01),但互相间无显著差异(P>0.05),然而肌增强因子(MEF 2C)具有极显著差异(P<0.01)且与其他指标极显著相关(P<0.01)。[结论]0~4周是鸭生长的关键期,需要更加严格的饲养管理;建议6周后开始选育工作,以降低鸭的应激。肌发育关键基因的表达水平差异是造成肌纤维差异的关键原因。
[Objectives]In order to understand the differences in postnatal growth rate and muscle fiber characteristics of Peking duck(P),Jinling white duck(J,new strain),and reciprocal offspring(PJ,JP),the bodyweight of 0-7 weeks old was measured,and the growth laws of four populations were explored by nonlinear regression model;the pectoral muscle tissues of 7-week-old male ducks were taken to compare the characteristics of muscle fibers and the expression level of related genes.[Methods]Two nonlinear models of Logistic and Gompertz were used to fit the growth curve,and the optimal model was selected by the degree of fit(R^(2))and the sum of squares of residuals(E).The corresponding relative growth rate,absolute growth rate,and heterosis rate of F_(1)were calculated;muscle fiber characteristics were analyzed and compared by muscle fiber tissue section and Image pro plus software;the expression levels of genes related to muscle development were detected by RT-qPCR.[Results]Logistic model was selected by P,PJ and JP;the Gompertz model was selected as the optimal model by J(R^(2)≥0.986,E≤751.49),and 4 weeks was the age of growth inflection when the body weight of P was the highest and that of J was the smallest.The relative growth rate of each group was similar,and the difference in absolute growth rate was more apparent.The absolute growth rate of the 4-week-old in JP had obvious heterosis,and the PJ showed heterosis after 6 weeks.There were extremely significant differences in muscle fiber diameter,cross-sectional area,and density among 7-week-old ducks(P<0.01).Besides,the expression level of each gene in F_(1)was the highest in P,which was extremely significantly different from that in J(P<0.01).In addition,the expression of myogenic factor 5(Myf 5)of F_(1)was different from that of its parents,but there was no significant difference between them(P>0.05).There was a significant difference in myocyte enhancer factor 2C(MEF2C)between F_(1)and its parents(P<0.01)and correlated with body weight(P<0.01).[Conclusions]0 to 4
作者
王晋
匡伟
何宗亮
高鹏
祝启钊
杨铭宣
杨海霞
虞徳兵
WANG Jin;KUANG Wei;HE Zongliang;GAO Peng;ZHU Qizhao;YANG Mingxuan;YANG Haixia;YU Debing(College of Animal Science and Technology,Nanjing Agricultural University,Nanjing 210095,China)
出处
《南京农业大学学报》
CAS
CSCD
北大核心
2022年第4期761-768,共8页
Journal of Nanjing Agricultural University
基金
畜禽江苏省种业振兴揭榜挂帅项目(核心种源攻关项目)(JBGS〔2021〕112)
江苏现代农业产业技术体系建设专项(JATS〔2020〕001)。
关键词
鸭
正反交
生长曲线
肌纤维
duck
reciprocal cross
growth curve
muscle fiber
