Sheperd A C, Maslanka M, Quinn D, Kung L
Department of Animal Science and Agricultural Biochemistry, College of Agricultural Sciences, University of Delaware, Newark 19717-1303, USA.
J Dairy Sci. 1995 Mar;78(3):565-72. doi: 10.3168/jds.S0022-0302(95)76667-X.
First-cutting alfalfa was wilted, harvested from alternate rows, left untreated or treated with additives containing lactic acid bacteria and enzymes (cellulase, amylase, and pectinase), and ensiled in bag silos. Inoculation increased lactic acid bacteria from 5 x 10(4) to 1 x 10(6) cfu/g of forage. Because treatments were bagged consecutively, the DM of treated silages was higher than that of untreated silage. However, after 4 d of ensiling, the pH of treated silage, about 4.3, was lower than that of untreated silage, 4.7, and remained lower throughout the ensiling period. After 177 d of ensiling, total lactate was about 25% higher, and ammonia N was about 40% lower, in treated silage. In addition, NDF and ADF contents were lower in treated than in untreated silage. Between 51 and 177 d of storage, glucose content increased in treated silage, but not in untreated silage, suggesting that some plant cell-wall hydrolysis occurred during prolonged storage. In vitro digestion of NDF did not differ among treatments during early incubation, but the extent of digestion after 36 and 48 h was lower in treated than in untreated silage. The microbial and enzyme silage additives used in this study improved fermentation characteristics and reduced fiber content of silage but decreased the in vitro digestibility of fiber.
首茬苜蓿进行萎蔫处理，从间隔行收割，不做处理或用含有乳酸菌和酶（纤维素酶、淀粉酶和果胶酶）的添加剂处理，然后装入袋式青贮窖青贮。接种使每克草料中的乳酸菌数量从5×10⁴cfu增加到1×10⁶cfu。由于处理是连续装袋，处理后的青贮饲料干物质含量高于未处理的青贮饲料。然而，青贮4天后，处理后的青贮饲料pH值约为4.3，低于未处理的青贮饲料（pH值4.7），且在整个青贮期内一直较低。青贮177天后，处理后的青贮饲料中总乳酸含量约高25%，氨态氮含量约低40%。此外，处理后的青贮饲料中中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）含量低于未处理的青贮饲料。在储存51至177天期间，处理后的青贮饲料中葡萄糖含量增加，而未处理的青贮饲料中未增加，这表明在长期储存期间发生了一些植物细胞壁水解。在体外消化试验中，早期培养期间各处理间中性洗涤纤维的消化率无差异，但36小时和48小时后，处理后的青贮饲料消化程度低于未处理的青贮饲料。本研究中使用的微生物和酶青贮添加剂改善了青贮饲料的发酵特性，降低了纤维含量，但降低了纤维的体外消化率。
