Macias Franco A, da Silva A E M, de Moura F H, Norris A B, Van Den Broek K, Valcheck M, de Mello A, Fonseca M
Department of Agriculture, Veterinary, and Rangeland Sciences, University of Nevada, Reno, Reno, NV 89557, USA.
Department of Natural Resources Management, Texas Tech University, Lubbock, TX 79409, USA.
Transl Anim Sci. 2021 Jun 21;5(3):txab103. doi: 10.1093/tas/txab103. eCollection 2021 Jul.
Exploring alternative supplementation sources capable of maximizing feed and water efficiency in nursing Holstein calves is often ignored. The goals herein involve investigating the effects of two isoenergetic supplements on a nonmedicated milk replacer diet on total water intake, milk water intake, fresh water intake, feed intake parameters, and performance of Holstein nursing bull calves. Twenty-three animals (body weight [BW] = 94.67 ± 12.07 kg, age = 67 days old) were randomly assigned to one of three treatments for 68 days: control (CON; ad libitum milk replacer, = 7), carbohydrate supplement (CHO; corn starch on top of ad libitum milk replacer-based diet, = 8), or lipid supplement (FAT; menhaden fish oil on top of ad libitum milk replacer-based diet, = 8). The isoenergetic supplementation consisted of 3% menhaden fish oil addition on DM basis for FAT. This was matched energetically with corn starch for the CHO group resulting in a 7% composition in DM basis. All animals were provided free access to mineral mix and 120 g daily dried microbrewer's spent grains (). Data were analyzed with the GLMMIX procedure of SAS in a completely randomized design with the diets as a fixed effect. Dry matter intake (DMI) adjusted by average daily gain (ADG; DMI/ADG) resulted in significantly lower values for supplemented groups with CON = 2.48, CHO = 2.38, and FAT = 2.27 kg/kg ( = 0.033). Energy intake values were lower for CON when analyzing metabolizable energy intake ( < 0.0001), net energy intake for maintenance ( < 0.0001), and net energy intake for gain ( < 0.0001), followed by CHO, and then FAT. Total water intake ( < 0.0001), milk water intake ( < 0.0001), and fresh water intake ( < 0.0001) all resulted in CHO consuming 0.5 L or less water than the other two treatments. Energy requirements as digestible energy ( < 0.0001), metabolizable energy ( < 0.0001), net energy for maintenance ( < 0.0001), and net energy for gain ( < 0.0001) were lower for CHO, followed by CON, and then FAT having the highest requirements. Similar results were observed for residual feed (; = 0.006) and residual water intakes (; = 0.902). Ultimately, no performance differences were detected with regards to BW (CON = 146.71, CHO = 146.25, and FAT = 150.48 kg; > 0.1). These results indicate that lipid-based and starch-based supplementation can potentially increase feed efficiency and decrease voluntary water intake without adversely affecting performance.
探索能够最大限度提高荷斯坦犊牛哺乳期饲料和水利用效率的替代补充来源往往被忽视。本文的目标是研究两种等能量补充剂对非药物代乳粉日粮的荷斯坦哺乳公牛犊总水摄入量、乳水摄入量、淡水摄入量、采食量参数和生长性能的影响。23头动物（体重[BW]=94.67±12.07千克，年龄=67日龄）被随机分配到三种处理之一，为期68天：对照组（CON；自由采食代乳粉，n = 7）、碳水化合物补充组（CHO；在自由采食代乳粉日粮基础上添加玉米淀粉，n = 8）或脂肪补充组（FAT；在自由采食代乳粉日粮基础上添加鲱鱼油，n = 8）。等能量补充剂在FAT组中以干物质为基础添加3%的鲱鱼油。这在能量上与CHO组的玉米淀粉相匹配，在干物质基础上形成7%的组成。所有动物均可自由获取矿物质预混料和每日120克干啤酒糟。数据采用SAS的GLMMIX程序进行分析，采用完全随机设计，日粮为固定效应。通过平均日增重（ADG；DMI/ADG）调整的干物质摄入量（DMI）在补充组中显著较低，CON组为2.48、CHO组为2.38、FAT组为2.27千克/千克（P = 0.033）。在分析代谢能摄入量（P < 0.0001）、维持净能摄入量（P < 0.0001）和生长净能摄入量（P < 0.0001）时，CON组的能量摄入量较低，其次是CHO组，然后是FAT组。总水摄入量（P < 0.0001）、乳水摄入量（P < 0.0001）和淡水摄入量（P < 0.0001）均导致CHO组比其他两种处理少消耗0.5升或更少的水。CHO组的可消化能量（P < 0.0001）、代谢能（P < 0.0001）、维持净能（P < 0.0001）和生长净能（P < 0.0001）的能量需求较低，其次是CON组，FAT组的需求最高。在剩余饲料（P = 0.006）和剩余水摄入量（P = 0.902）方面观察到类似结果。最终，在体重方面未检测到性能差异（CON组=146.71、CHO组=146.25、FAT组=150.48千克；P > 0.1）。这些结果表明，基于脂肪和淀粉的补充剂可能会提高饲料效率并减少自愿水摄入量，而不会对生长性能产生不利影响。
