Developing breeding objectives for beef cattle production 2. Biological and economic values of growth and carcass traits in Japan
Developing breeding objectives for beef cattle production 2. Biological and economic values of growth and carcass traits in Japan
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制定肉牛生产育种目标 2. 日本生长和胴体性状的生物学和经济价值
DOI：
10.1017/s135772980000919x
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
J. Hillers
中科院分区：
文献类型：
--
作者：
H. Hirooka;A. Groen;J. Hillers
使用模拟奶牛及其后代生命周期中牛肉生产的确定性生物经济模型来估计日本三种生产系统（母牛-小牛、饲养场和综合）和替代生产环境的日增重、大理石花纹得分、出生体重、断奶体重和成熟体重的生物学和经济价值。生物效率（活重和瘦体重）和经济效益（成本回报）被视为育种目标。替代方案包括减少最大繁殖周期数、通过恒定屠宰重量 (BASE) 进行营销、恒定日龄或恒定胴体脂肪含量、减轻屠宰重量以及将食品价格提高一倍。母牛-犊牛系统以活重为基础的生物效率受断奶体重增加的影响最大；对于饲养场和综合系统，日增重的增加影响最大。对于精益生产的生物效率，日增重和成熟体重的增加分别对饲养场和综合系统影响最大。就经济效益而言，增加断奶重量在母牛-犊牛系统中最有利，而增加大理石花纹分数在饲养场和综合系统中最有利。随着这些性状遗传水平的增加，日增重和断奶体重的经济价值显着下降。按年龄进行营销降低了日增重的生物学价值，但增加了日增重的经济价值。以恒定胴体脂肪含量进行营销降低了成熟体重的生物学价值，但增加了成熟体重的经济价值。屠宰体重的下降导致日增重和断奶体重的经济价值为负。当食品价格翻倍时，经济价值就会下降。
A deterministic bio-economic model simulating beef production during the life cycle of a cow and her offspring was used to estimate biological and economic values of daily gain, marbling score, birth weight, weaning weight and mature weight for three production systems (cow-calf, feedlot and integrated) and alternative production circumstances in Japan. Biological efficiency (live-weight basis and lean-weight basis) and economic efficiency (returns over costs) were regarded as breeding objectives. Alternatives included reducing the maximum number of reproductive cycles, marketing by constant slaughter weight (BASE), constant age or constant carcass fat content, lighter slaughter weight and doubling food prices. Biological efficiency on a live-weight basis for the cow-calf system was most influenced by increasing weaning weight; for the feedlot and integrated system, increasing daily gain had the largest influence. For biological efficiency of lean production, increasing daily gain and mature weight had the largest influence in the feedlot and integrated systems, respectively. For economic efficiency, increasing weaning weight was most beneficial in the cow-calf system and increasing marbling score was most beneficial in the feedlot and integrated systems. Economic values of daily gain and weaning weight decreased markedly with increasing genetic levels of these traits. Marketing by age decreased the biological values of daily gain but increased the economic value of daily gain. Marketing at a constant carcass fat content decreased biological values of mature weight but increased the economic value of mature weight. Decreasing slaughter weight provided negative economic values of daily gain and weaning weight. Economic values were reduced when food prices were doubled.