PDF(Pubmed)
Abstract：
The aim of this study was to evaluate whether the starch levels in pellets fed to cows in automatic milking systems (AMS) affect subacute ruminal acidosis (SARA) occurrence and metabolite parameters. Twenty-four lactating cows (124.4 ± 49.9 days in milk) were studied in a crossover design with two periods of 21 days each and two treatment groups-a control group fed AMS pellets containing 30.0% of starch dry matter (DM) and an experimental group fed AMS pellets containing 23.5% of starch DM. All cows received the same partial mixed ration (PMR). The 1-hr mean ruminal pH in both groups decreased over 4 hr after feeding on PMR but recovered by the next morning. The ruminal pH was unaffected by either treatment, and both groups developed SARA. The groups had no significant differences in the concentrations of ruminal volatile fatty acids, lipopolysaccharides, plasma acute-phase proteins, other metabolites, and hormones. The milk yield and composition were not different in both groups. Feeding low-starch pellets in the AMS did not contribute to the risk of SARA occurrence in cows and had no additive effects on rumen fermentation, plasma metabolites, or milk production.
摘要：
这项研究的目的是评估在自动挤奶系统（AMS）中饲喂奶牛的颗粒中的淀粉水平是否会影响亚急性瘤胃酸中毒（SARA）的发生和代谢参数。在交叉设计中研究了24头泌乳母牛（牛奶中124.4±49.9天），每个周期为21天，两个处理组-对照组饲喂含有30.0％淀粉干物质（DM）的AMS颗粒，实验组饲喂含有23.5％淀粉DM的AMS颗粒。所有奶牛接受相同的部分混合日粮(PMR)。饲喂PMR后，两组的1小时平均瘤胃pH值均在4小时内降低，但在第二天早晨恢复。瘤胃pH值不受任何一种处理的影响，两组都发展为SARA。各组瘤胃挥发性脂肪酸浓度无显著差异,脂多糖，血浆急性期蛋白，其他代谢物，和荷尔蒙。两组的产奶量和组成没有差异。在AMS中饲喂低淀粉颗粒不会导致奶牛发生SARA的风险，并且对瘤胃发酵没有累加作用。血浆代谢物，或牛奶生产。
