文献类型： 外文期刊

作者： Liu, Q. ¹ ; Wang, C. ¹ ; Yang, W. Z. ¹ ; Zhang, B. ¹ ; Yang, X. M. ³ ; He, D. C. ³ ; Zhang, P. ⁴ ; Dong, K. H. ¹ ; Huang, Y. ¹ ;

作者机构： 1.Shanxi Agr Univ, Coll Anim Sci & Vet Med, Taigu 030801, Shanxi, Peoples R China

2.Agr & Agri Food Canada, Res Ctr, Lethbridge, AB, Canada

3.Shanxi Acad Agr Sci, Inst Anim Sci, Taiyuan 030032, Shanxi, Peoples R China

4.Datong State Dairy Cow Farm, Datong 037004, Shanxi, Peoples R China

关键词： Isobutyrate;Rumen fermentation;Lactation performance;Blood metabolites

期刊名称：ANIMAL FEED SCIENCE AND TECHNOLOGY （ 影响因子：3.247； 五年影响因子：3.806 ）

ISSN： 0377-8401

年卷期： 2009 年 154 卷 1-2 期

页码：

收录情况： SCI

摘要： The objective of this study was to evaluate effects of isobutyrate supplementation on rumen fermentation, lactation performance and plasma characteristics of dairy cows. Twenty multiparous second filial generation (F2) cows of a cross between Chinese Jinnan Yellow and Holstein cows at 148 +/- 4.5 days in milk and 22.3 +/- 0.81 kg milk production were used in a replicated 4 x 4 Latin square experiment. The treatments were: control (without isobutyrate), low (LIB), medium (MIB) and high (HIB) isobutyrate supplementation of 20, 40 and 60 g per cow per day, respectively. Experimental periods were 30 days with 15 d of adaptation and 15 d of data collection. Dry matter (DM) intake was not affected by increasing isobutyrate supplementation, but milk yields were highest for the 40 g/d isobutyrate supplementation level, where proportion of milk fat, true protein and lactose were minimized. Ruminal pH (6.38-6.24) and ammonia N (13.8-11.1 mg/100 ml) were linearly (P<0.01) decreased, whereas total VFA concentration (124-131 mM) increased at a decreasing rate with increasing isobutyrate supplementation. The ratio of acetate to propionate increased linearly (P<0.01) from 2.77 to 4.43 as isobutyrate supplementation increased due to the increase in acetate production and decrease in propionate production. Digestibilities of OM in the total tract increased linearly (P<0.01) as isobutyrate supplementation increased, digestibilities of DM and EE were highest for the 40 g/d isobutyrate supplementation level, digestibilities of CP, aNDF and AN increased at a decreasing rate with increasing isobutyrate supplementation. Plasma concentrations of glucose and growth hormone linearly (P<0.03) increased, whereas concentrations of non-esterified fatty acids linearly (P<0.01) decreased. Results indicate that supplementation of this diet with isobutyrate changed the rumen fermentation pattern towards acetate production, improved digestion and modified plasma concentrations of glucose and growth hormone. This Suggests that isobutyrate stimulated digestive microorganisms or enzymes in a dose-dependent manner with the Optimum isobutyrate dose at about 40 g per cow per day in terms of improved digestion. (C) 2009 Elsevier B.V. All rights reserved.