12～13月龄生长母水牛能量需要量初探

Preliminary Study on Energy Requirement of 12～13 Months Buffalo Heifers

本研究旨在通过试验手段研究生长母水牛能量需要量。试验选用12头体况良好，12～13月龄，体重相近[（209±20）kg]的健康生长母水牛，按随机区组的试验设计分为3组进行能量平衡试验，通过测定能量摄入量、消化率、产热量等研究其能量需要。3组试验日粮均由精料和粗料（象草和发酵菠萝皮）组成。3组精料粗蛋白质水平一致（17．5％），能量水平不同，产奶净能分别为6．71、6．40和6．07MJ／kg。饲养试验包括15d预试期和30d正试期，在正试期第24和28天分别进行为期7d的消化代谢试验和3d的气体代谢试验。试验结果表明，本研究条件下，12-13月龄生长母水牛正常采食状态下产热量（HP）为0．551MJ／（W^0.75·d），能量消化率为66．49％，能量代谢率为50．34％。生长母水牛用于维持的净能需要量为0．401MU／（W^0.75·d），每增重1kg所需要的净能为19．00MJ。12～13月龄生长母水牛净能总需要量可以按以下公式计算：NE（MJ／d）=（0．401＋0．319△W）W^0.75或NE（MJ／d）=0．401W^0.75＋19．00△W，式中△W为牛只日增重（kg／d）。

The objective of this study was to investigate the energy requirement of growing buffalo heifers. Twelve buffalo heifers, aged 12- 13 months with an initial body weight of （209 ± 20） kg were divided into 3 groups by randomized complete block design to carry out an energy balance trial. The animals were divided according to their body weight and breed and received one of 3 diets containing the same forage but different concentrate mixtures of varying levels of net energy for lactation： 6.71, 6.40 and 6.07 MJ/kg, respectively. The elephant grass and fermented pineapple peel were the main ingredients of forage. The whole experiment was lasted for 45 days with the first 15 days for adaptation. Seven-day digestion and 3-d respiratory gas metabolism tests were conducted on the 24th and 28th day of feeding trial, respectively. The results showed that the heat production for 12-13 months buffalo heifers was 0. 551 MJ/ （W^0.75·d）. Digestibility and metabolizability of energy were 66.49% and 50.34%, respectively. The net energy required for maintenance was 0.401 MJ/ （W^0.75·d） and for growth was 19.00 MJ/kg. It was concluded that the requirement for total net energy of 12-13 months buffalo heifers could be estimated by the following equations.. NE（MJ/d） = （0. 401 ＋ 0. 319△W） W^0.75 or NE（MJ/d） = 0. 401 W^0.75 ＋ 19.00△W, where △W was average daily gain （kg/d）.