宁夏固原地区秦川牛杂交改良效果研究及通径分析

Research on Crossbreeding Effect and Path Analysis of Qinchuan Cattle in Guyuan Ningxia

以成年安秦牛(安格斯牛♂×秦川牛♀)母牛和秦川牛母牛为研究对象,探究安格斯牛杂交改良秦川牛的效果,并通过体尺性状对其体重进行评估,剖分安秦牛和秦川牛母牛各体尺性状对体重的影响。试验共测定了47头安秦牛和152头秦川牛成年母牛群体的体高、体斜长、胸围、腰角宽和坐骨端宽5个体尺数据,并称量其体重;采用逐步线性回归的方法分别建立安秦牛和秦川牛母牛体重与体尺的多元线性回归方程;利用通径分析的方法计算各体尺性状对体重的直接作用和间接作用。结果表明:安秦牛母牛在体重、胸围和坐骨端宽3个指标优于秦川牛母牛(P<0.01);相较于秦川牛母牛,安秦牛母牛在体重、坐骨端宽、胸围和腰角宽分别提高13.0%、9.9%、3.5%和3.3%。安秦牛和秦川牛母牛体重与体尺的多元线性回归方程分别为Y=-912.849+4.899X_(1)+3.866X_(3)和Y=-718.128+1.881X_(2)+2.995X_(3)+4.386X_(4)+5.057X_(5),其中Y为体重(kg),X_(1)为体高(cm)、X_(2)为体斜长(cm)、X_(3)为胸围(cm)、X_(4)为腰角宽(cm)、X_(5)为坐骨端宽(cm);胸围对体重的直接作用大于其他体尺性状的直接作用。综上所述,安格斯牛对秦川牛杂交改良效果显著,建立的多元线性回归方程可应用于安秦牛和秦川牛母牛的良种选育,表明胸围是反映安秦牛和秦川牛母牛体重的主要指标。

In this study,the effects of crossbreeding of Angus cattle to improve Qinchuan cattle were investigated,taking the adult female Anqin cattle(Angus♂×Qinchuan♀)and female Qinchuan cattle as research object.Its body weight was evaluated by body size traits,and the effects of body size traits on body weight of Qinchuan cattle and Angus cattle were analyzed.Data of five body size of 47 female Anqin cattle and 152 adult female Qinchuan cattle were collected,including height at withers,body length,heart girth,hip width,pin bone width,and their weight were also measured.Multiple linear regression equations were established by stepwise multiple linear regression.Then the direct and indirect effects of each body size on weight were calculated by path analysis.The results suggested that Anqin female cattle outperforms Qinchuan female cattle in three indicators of weight,heart girth and pin bone width(P<0.01);compared with Qinchuan female cattle,Anqin female cattle's weight,pin bone width,heart girth and hip-width increased by 13.0%,9.9%,3.5%and 3.3%respectively.The multiple linear regression equations of Anqin and Qinchuan female cattle weight and body size are respectively Y=-912.849+4.899X_(1)+3.866X_(3) and Y=-718.128+1.881X_(2)+2.995X_(3)+4.386X_(4)+5.057X_(5)(Y is body weight(kg),X_(1) is height at withers(cm),X_(2) is body length(cm),X_(3) is heart girth(cm),X_(4) is hip width(cm),X_(5) is pin bone width(cm));the direct effect of bust on body weight is greater than the direct effect of other body size traits.In conclusion,Angus cattle has a significant effect on Qinchuan cattle hybridization,and the multiple linear regression equations can be used for selective breeding in Anqin and Qinchuan female cattle,and the dominant factor of impacting the weight of Anqin female cattle and Qinchuan female cattle is the heart girth.