Evaluation of forage-based weaning systems in spring-born cross-bred beef calves
Evaluation of forage-based weaning systems in spring-born cross-bred beef calves作者机构：Division of Animal and Nutritional Sciences West Virginia University Morgantown USA West Virginia University Extension Service Randolph County Extension Office Elkins USA
出 版 物：《Open Journal of Animal Sciences》 (动物科学期刊（英文）)
年 卷 期：2013年第3卷第2期
页 面：99-104页
学科分类：1002[医学-临床医学] 100214[医学-肿瘤学] 10[医学]
主 题：Preconditioning Beef Calves Early Weaning Weight Gain
摘 要：Preconditioned calves have greater marketvalue per unit weight than normal-weaned calves. Development of a low cost forage-based preconditioning system allows producers to add value to their calf-crop. This study evaluated calf performance in three forage-based weaning systems;early-weaned calves were backgrounded in legume/grass forage plots and supplemented with commercial preconditioning feed (Treatment 1) or an on-farm corn-mix (Treatment 2). Control (Treatment 3) calves suckled for an additional 45 days. Supplements provided2.17 kgTDN/calf/ day. Weights were collected on days -30, 0 and 45 with respect to early weaning, from135 inyear 1 and 150 calves in each of the two subsequent years. Effects of treatment, age of dam, sex of calf and their interactions on calf weight gain were analyzed by analysis of covariance using GLM procedures of SAS. Marginal effects of treatment and feed cost were used to evaluate economic feasibility. Sensitivity analyses were evaluated for anticipated market fluctuations in feed costs and calf premiums. Data are reported as least squares means. Calf weight gains differed (P 0.001) among treatments and averaged 1.16, 1.03 and1.04 kg/calf/day for commercial supplement, corn-mix and controls, respectively. Calves from 2-year-old cows gained less (P 0.001) weight compared to those from cows 3 - 4 and ≥5 years of age (44.8, 48.9 and51.5 kg, respectively). Steers calves gained more (P 0.001) weight compared to heifer calves (51.2 vs.45.7 kg, respectively). Net returns for corn mix were greater than those for commercial feed ($1.48 vs. $1.35/kg weight gain, respectively). Sensitivity analyses indicated that selection of preconditioning treatment to a large degree was less sensitive to significant changes in market conditions due to the large gap in marginal costs between the two treatments. In conclusion, forage-based weaning systems can be utilized to precondition calves providing an economical means for calf weight gain and profit
维普期刊数据库