黑龙江动物繁殖2026，Vol.34Issue(4)：52-57,6.DOI:10.19848/j.cnki.ISSN1005-2739.2026.08.0009
西门塔尔、比利时蓝牛杂交母本外部骨盆指数与难产风险的关联
Association between the external pelvic index and dystocia risk in Simmental dams bred to Belgian Blue siresused for Belgian Blue crossbreeding
摘要
Abstract
This study aimed to investigate the association between the external pelvic index of Simmental dams and the risk of dystocia following breeding to Belgian Blue sires.A total of 225 Simmental cows maintained under uniform feeding and management conditions on a single commercial farm were included.Before breeding,body weight,withers height,oblique body length,chest girth,hook width,hip width,pin width,and rump length were measured.The external pelvic index was calculated as the arithmetic mean of hook width,hip width,and pin width.Based on calving records,the cows were classified into a normal-calving group(n=209)and a dystocia group(n=16).Statistical analyses included independent-samples t tests,Cohen 's d effect sizes,Pearson correlation analysis,univariable binary logistic regression,and receiver operating characteristic(ROC)curve analysis.The results showed that body weight,withers height,oblique body length,chest girth,hook width,hip width,pin width,and the external pelvic index were all significantly lower in the dystocia group than in the normal-calving group(P<0.05).Among these variables,the external pelvic index,pin width,and hook width showed relatively large between-group effect sizes.The external pelvic index was significantly and positively correlated with hook width,hip width,and body weight(P<0.01).Univariable logistic regression analysis showed that a higher external pelvic index was associated with lower odds of dystocia(odds ratio=0.339,95%confidence interval:0.225-0.511,P<0.001).ROC curve analysis showed that the area under the curve for the external pelvic index was 0.935(95%CI:0.866-1.000,P<0.001).At a cutoff value of 37.5 cm,the sensitivity and specificity were 87.5%and 91.9%,respectively.In conclusion,the external pelvic index may reflect the transverse skeletal development of the hindquarters in Simmental dams used for crossbreeding and may serve as a candidate indicator for pre-breeding screening of individuals at high risk of dystocia.However,the proposed cutoff value and discriminatory performance require further external validation across different farms and cattle populations.关键词
比利时蓝牛/西门塔尔牛/体尺性状/外部骨盆指数/难产/ROC曲线Key words
Belgian Blue cattle/Simmental cattle/body measurements/external pelvic index/dystocia/receiver operating characteristic curve分类
农业科技引用本文复制引用
刘佳楠,张磊,李小鹏,蒋超祥,侯永峰,王洁茹,宋鹏琰,何婷婷,方翟..西门塔尔、比利时蓝牛杂交母本外部骨盆指数与难产风险的关联[J].黑龙江动物繁殖,2026,34(4):52-57,6.基金项目
新疆生产建设兵团科技计划项目-重点领域科技攻关计划项目(2025AB082) （2025AB082）
