精料中碳水化合物来源及棉籽粕水平对青年奶牛采食量、养分消化率、瘤胃发酵和微生物蛋白合成的影响
Effect of carbohydrate sources and levels of cotton seed meal in concentrate on feed intake, nutrient digestibility, rumen fermentation and microbial protein synthesis in young dairy bulls.
作者信息
Wanapat M, Anantasook N, Rowlinson P, Pilajun R, Gunun P
机构信息
Tropical Feed Resources Research and Development Center (TROFREC), Department of Animal Science, Faculty of Agriculture, Khon Kaen University, Khon Kaen 40002, Thailand.
出版信息
Asian-Australas J Anim Sci. 2013 Apr;26(4):529-36. doi: 10.5713/ajas.2012.12607.
The objective of this study was to investigate the effect of levels of cottonseed meal with various carbohydrate sources in concentrate on feed intake, nutrient digestibility, rumen fermentation and microbial protein synthesis in dairy bulls. Four, 6 months old dairy bulls were randomly assigned to receive four dietary treatments according to a 2×2 factorial arrangement in a 4×4 Latin square design. Factor A was carbohydrate source; cassava chip (CC) and cassava chip+rice bran in the ratio of 3:1 (CR3:1), and factor B was cotton seed meal levels in the concentrate; 109 g CP/kg (LCM) and 328 g CP/kg (HCM) at similar overall CP levels (490 g CP/kg). Bulls received urea-lime treated rice straw ad libitum and were supplemented with 10 g of concentrate/kg BW. It was found that carbohydrate source and level of cotton seed meal did not have significant effects on ruminal pH, ammonia nitrogen concentration, microbial protein synthesis or feed intake. Animals which received CC showed significantly higher BUN concentration, ruminal propionic acid and butyric acid proportions, while dry matter, organic matter digestibility, populations of total viable bacteria and proteolytic bacteria were lower than those in the CR3:1 treatment. The concentration of total volatile fatty acids was higher in HCM than LCM treatments, while the concentration of butyric acid was higher in LCM than HCM treatments. The population of proteolytic bacteria with the LCM treatments was higher than the HCM treatments; however other bacteria groups were similar among the different levels of cotton seed meal. Bulls which received LCM had higher protein digestibility than those receiving HCM. Therefore, using high levels of cassava chip and cotton seed meal might positively impact on energy and nitrogen balance for the microbial population in the rumen of the young dairy bull.
本研究的目的是调查精饲料中不同碳水化合物来源的棉籽粕水平对奶牛公牛采食量、养分消化率、瘤胃发酵和微生物蛋白合成的影响。将四头6月龄的奶牛公牛按照2×2析因设计，采用4×4拉丁方设计随机分配接受四种日粮处理。因素A为碳水化合物来源，木薯片（CC）和木薯片+米糠（比例为3:1，即CR3:1）；因素B为精饲料中棉籽粕水平，在相似的总粗蛋白水平（490 g CP/kg）下，分别为109 g CP/kg（低棉籽粕，LCM）和328 g CP/kg（高棉籽粕，HCM）。公牛自由采食经尿素-石灰处理的稻草，并按每千克体重补充10 g精饲料。结果发现，碳水化合物来源和棉籽粕水平对瘤胃pH值、氨氮浓度、微生物蛋白合成或采食量没有显著影响。采食CC的动物血尿素氮浓度、瘤胃丙酸和丁酸比例显著较高，而干物质、有机物消化率、总活菌数和蛋白水解菌数均低于CR3:1处理组。HCM处理组的总挥发性脂肪酸浓度高于LCM处理组，而LCM处理组的丁酸浓度高于HCM处理组。LCM处理组的蛋白水解菌数量高于HCM处理组；然而，在不同棉籽粕水平之间，其他细菌组相似。采食LCM的公牛比采食HCM的公牛具有更高的蛋白质消化率。因此，使用高水平的木薯片和棉籽粕可能对年轻奶牛公牛瘤胃中微生物群体的能量和氮平衡产生积极影响。
Zotero 插件