In growing cattle, the phenotypic and genetic relationships between feeding behavior and both live animal ultrasound measures and subsequent carcass merit are generally poorly characterized. The objective of the current study was to quantify the phenotypic and genetic associations between a plethora of feeding behavior traits with both pre-slaughter ultrasound traits and post-slaughter carcass credentials in crossbred Bos taurus cattle. Carcass data were available on 3,146 young bulls, steers, and heifers, of which 2,795 and 2,445 also had records for pre-slaughter ultrasound muscle depth and intramuscular fat percentage, respectively; a total of 1,548 steers and heifers had information on all of the feeding behavior, ultrasound, and carcass traits. Young bulls were fed concentrates, while steers and heifers were fed a total mixed ration. Feeding behavior traits were defined based on individual feed events or meal events (i.e., individual feed events grouped into meals). Animal linear mixed models were used to estimate (co)variance components. Phenotypic correlations between feeding behavior and both ultrasound and carcass traits were generally weak and not different from zero, although there were phenotypic correlations of 0.40, 0.26, and 0.37 between carcass weight and feeding rate, energy intake per feed event, and energy intake per meal, respectively. Genetically, cattle that had heavier carcass weights, better carcass conformation, or a higher dressing percentage fed for a shorter time per day (genetic correlations [±SE] of −0.46 ± 0.12, −0.39 ± 0.11, and −0.50 ± 0.10, respectively). Genetic correlations of 0.43 ± 0.12 and 0.68 ± 0.13 were estimated between dressing difference (i.e., differential between live weight pre-slaughter and carcass weight) and energy intake per feed event and energy intake per meal, respectively. Neither intramuscular fat percentage measured on live animals nor carcass fat score (i.e., a measure of subcutaneous fat cover of the carcass) was genetically associated with any of the feeding behavior traits. The genetic associations between some feeding behavior traits and both ultrasound and carcass traits herein suggested that indirect responses in the feeding behavior of growing cattle from selection for improved carcass merit would be expected. Such changes in feeding behavior patterns in cattle may be reduced by measuring and including feeding behavior in a multiple-trait selection index alongside carcass traits.

中文翻译：

---

杂交生长牛摄食行为与胴体价值之间的表型和遗传关联

在生长的牛中，喂养行为与活体动物超声测量和随后的胴体价值之间的表型和遗传关系通常难以表征。当前研究的目的是量化杂交 Bos taurus 牛的大量喂养行为特征与屠宰前超声特征和屠宰后尸体凭证之间的表型和遗传关联。可获得 3,146 头年轻公牛、阉牛和小母牛的胴体数据，其中 2,795 头和 2,445 头分别有屠宰前超声肌肉深度和肌内脂肪百分比的记录；共有 1,548 头阉牛和小母牛掌握了所有喂养行为、超声波和胴体特征的信息。小公牛饲喂浓缩饲料，而阉牛和小母牛则饲喂全混合日粮。进食行为特征是根据个体进食事件或进餐事件（即，个体进食事件分组为进餐）定义的。动物线性混合模型用于估计（协）方差分量。采食行为与超声波和屠体性状之间的表型相关性通常较弱且与零无异，尽管屠体重量与采食率、每次采食事件的能量摄入量和每餐能量摄入量之间的表型相关性分别为 0.40、0.26 和 0.37 ， 分别。从遗传上讲，胴体重量较重、胴体形态较好或屠宰率较高且每天喂食时间较短的牛（遗传相关性 [±SE] 分别为 -0.46 ± 0.12、-0.39 ± 0.11 和 -0.50 ± 0.10 ). 遗传相关性为 0.43 ± 0.12 和 0.68 ± 0。13 分别在屠宰差异（即，屠宰前活重和胴体重量之间的差异）和每次饲料事件的能量摄入和每餐能量摄入之间进行估计。无论是活体动物的肌内脂肪百分比还是胴体脂肪评分（即，胴体皮下脂肪覆盖的量度）都与任何摄食行为特征没有遗传相关性。本文中某些摄食行为特征与超声波和胴体特征之间的遗传关联表明，生长牛的摄食行为会因选择改善胴体品质而产生间接反应。通过测量并将摄食行为包括在多性状选择指数中以及胴体性状中，可以减少牛摄食行为模式的这种变化。屠宰前活重和屠体重量之间的差异）和每次饲料事件的能量摄入量和每餐的能量摄入量，分别。无论是活体动物的肌内脂肪百分比还是胴体脂肪评分（即，胴体皮下脂肪覆盖的量度）都与任何摄食行为特征没有遗传相关性。本文中某些摄食行为特征与超声波和胴体特征之间的遗传关联表明，生长牛的摄食行为会因选择改善胴体品质而产生间接反应。通过测量并将摄食行为包括在多性状选择指数中以及胴体性状中，可以减少牛摄食行为模式的这种变化。屠宰前活重和屠体重量之间的差异）和每次饲料事件的能量摄入量和每餐的能量摄入量，分别。无论是活体动物的肌内脂肪百分比还是胴体脂肪评分（即，胴体皮下脂肪覆盖的量度）都与任何摄食行为特征没有遗传相关性。本文中某些摄食行为特征与超声波和胴体特征之间的遗传关联表明，生长牛的摄食行为会因选择改善胴体品质而产生间接反应。通过测量并将摄食行为包括在多性状选择指数中以及胴体性状中，可以减少牛摄食行为模式的这种变化。