MILK REPLACER USE IN SUBSTITUTION OF WHOLE MILK ON THE PERFORMANCE OF HOLSTEIN CALVES DURING GROWING PHASE

Abstract The objective of this study was to evaluate the biological efficiency of the milk replacer in the substitution of whole milk for calves at the first months of age and at rearing fase. This study was conducted in Universidade Tecnológica Federal do Paraná (UTFPR), Campus Dois Vizinhos, from May 2011 to April 2012. This research was carried out on 32 animals, assigned in a completely randomized design with four treatments (100% whole milk, 34% milk replacer + 66% whole milk, 66% milk replacer + 34% whole milk and 100% milk replacer) and eight replications.The data were analyzed by analysis of variance and regression at 5% of significance. Regarding the morphometric measurements, only the gain of chest circumference presented significant difference. The use of milk replacer in the substitution of whole milk during pre-weaning phase showed negative linear response for levels 100%, 66%, 34% milk replacer, nevertheless during the post-weaning phase there was a compensatory gain for the animals fed with 34% and 66 % milk replacer. The use of 100% milk replacer for Holstein calves at pre-weaning phase was not efficient during lactation, althoug, during post-weaning phase, partial replacement of milk by milk replacer (66% + 34% milk replacer) was an efficient option because there was a favorable compensatory growth.摘要 本研究旨在评估代乳粉（milk replacer）替代月龄早期犊牛全脂乳的生物学效率，及其在育成阶段的应用效果。本实验于2011年5月至2012年4月在巴拉那联邦理工大学（Universidade Tecnológica Federal do Paraná，UTFPR）多伊斯维金诺斯校区开展。研究选取32头犊牛，采用完全随机设计，设置4组处理：100%全脂乳组、34%代乳粉+66%全脂乳组、66%代乳粉+34%全脂乳组及100%代乳粉组，每组设8次重复。数据采用方差分析与回归分析进行统计处理，显著性水平设定为5%。形态学测量结果显示，仅胸围增长量存在显著差异。断奶前阶段使用代乳粉替代全脂乳时，当代乳粉添加比例为100%、66%、34%时，犊牛生长呈现负线性响应；而断奶后阶段，饲喂34%与66%代乳粉组的犊牛出现补偿性生长。泌乳期内，断奶前阶段采用100%代乳粉饲喂荷斯坦犊牛的效果欠佳；但在断奶后阶段，采用代乳粉部分替代全脂乳（66%代乳粉+34%全脂乳）为高效方案，该组犊牛呈现出有利的补偿性生长。