This study was carried out to investigate the effect of nano-zinc oxide supplementation on rumen fermentation in vitro. Five levels of nano-zinc oxide supplementation were 0, 50, 100, 200, 400 mg/kg of DM, respectively. Culture medium in vitro was sampled to determine pH, ammonia nitrogen (NH3-N), microbial crud protein (MCP), volatile fatty acids (VFA) and fermentation of organic matter. Results from this study showed that pH was not affected by adding different levels of nano-zinc oxide (P＞0.05). The concentration of VFA and MCP production and the fermentation of organic matter were significantly increased (P＜0.05), while the concentration of ammonia nitrogen and the ratio of acetate to propionate were significantly decreased (P＜0.05) with the supplementation levels of 100 and 200 mg/kg of nano-zinc oxide at the 6th and 12th hour of incubation in vitro. In conclusion, the supplementation of nano-zinc oxide can improve the growth of ruminal microorganisms, increase the ruminal microbial protein synthesis, and raise the energy utilization efficiency in early phase(6 to 12 h) of incubation in vitro.［Chinese Journal of Animal Nutrition, 2011, 23（8）：1415 -1421］
［1］NUNNERY G A, VASCONCELOS J T, PARSONS C H, et al. Effects of source of supplemental zinc on performance and humoral immunity in beef heifers[J]. Journal of Animal Science, 2007, 85(9):2304-2313.
[2]姚军虎,曹斌云,窦铖,等.锌对青年牛生长发育的影响[J].西北农业大学学报,1996,24(4):55-58.
[3]HUBBERT F J, CHEN S, BURROUGHS W. Mineral requirement of rumen microorganisms for cellulose digestion in vitro[J]. Journal of Animal Science, 1958, 17:559-568.
[4]FROETSCHE M A, MARTIN A C, AMOS H E, et al. Effects of zinc sulfate concentration and feeding frequency on ruminal protozoal numbers, fermentation patterns and amino acid passage in steers[J]. Journal of Animal Science, 1990, 68(9):2874-2884.
[5]BATEMAN J, WILLIAMS C C, HUANG Y H, et al. Effects of supplemental zinc in high quality diets on ruminal fermentation and degradation of urea in vitro and in vivo[J]. The Professional Animal Scientist, 2002, 18(4):363-367.
[6]王之盛,况应谷,任守国,等.纳米氧化锌对仔猪生产性能和粪便微生物群落的影响[J].中国畜牧杂志,2006,42(9):22-24.
[7]田丽娜,朱风华,任慧英,等.纳米氧化锌对肉仔鸡抗氧化性能的影响[J].动物营养学报,2009,21(4):534-539.
[8]MENKE K H, STEINGASS H. Estimation of the energetic feed value obtained from chemical analysis and in vitro gas production using rumen fluid[J]. Animal Research and Development, 1988, 28:7-55.
[9]冯宗慈,高民.通过比色法测定瘤胃液氨氮含量方法的改进[J].内蒙古畜牧科学,1993,4:40-41.
[10]ZINN R A, OWENS F N. A rapid procedure for purine measurement and its use for estimating net ruminal protein synthesis[J]. Canadian Journal of Animal Science, 1986, 66:157-166.
[11]MAKKAR H P S, BECKER K. Purine quantification in digesta from ruminants by spectrophotometric and HPLC methods[J]. British Journal of Nutrition, 1999, 81:107-112.
[12]杨胜.饲料分析及饲料质量检测技术[M].北京:北京农业大学出版社,1991:17-28.
[13]BROWN M S, PONCE C H, PULIKANTI R, et al. Adaptation of beef cattle to high-concentrate diets: performance and ruminal metabolism[J]. Journal of Animal Science, 2006, 84:E25-E33.
[14]CALSAMIGLIA S, FERRET A, DEVANT M, et al. Effects of pH and pH fluctuations on microbial fermentation and nutrient flow from a dual-flow continuous culture system[J]. Journal of Dairy Science, 2002, 85(3):574-579.
[15]ARELOVICH H M, OWENS F N, HORN G W, et al. Effects of supplemental zinc and manganese on ruminal fermentation, forage intake, and digestion by cattle fed prairie hay and urea [J]. Journal of Animal Science, 2000, 78(11):2972-2979.
[16]ALLISON M N, SMITH R H. Biosynthesis of amino acids by ruminal microorganisms[J]. Journal of Animal Science, 1967, 29:797-807.
[17]ZEREBCOV P I, NABIEV N H. Effect of different amounts of Zn on N and carbohydrate metabolism in the rumen of cattle[J]. Nutrition Abstract Research, 1971, 41:130.
[18]ARELOVICH H M, LABORDE H E, AMELA M I, et al. Effects of dietary addition of zinc and (or) monensin on performance, rumen fermentation and digesta kinetics in beef cattle[J]. Spanish Journal of Agricultural Research, 2008, 6(3):362-372.
[19]KENNEDY D W, CRAIG W M, SOUTHERN L L, et al. Ruminal distribution of zinc in steers fed a polysaccharide complex or zinc oxide[J]. Journal of Animal Science, 1993, 71(5):1281.
[20]张吉鹍,邹庆华,钟小军.稻草添补矮象草体外发酵组合效应的综合评定研究[J].中国畜牧杂志,2008,44(21):38-41．
[21]匡伟,郭玉华,尹召华,等.利用体位法研究不同水平维生素A对奶牛瘤胃内环境参数的影响[J].动物营养学报,2006,18(3):197-202.
[22]BATEMAN H G, WILLIAMS C C, GANTT D T, et al. Effects of zinc and sodium monensin on ruminal degradation of lysine-HCl and liquid 2-hydroxy-4-methylthiobutanoic acid[J]. Journal of Dairy Science, 2004, 87(8):2571-2577.
[23]王峰,莫放,黄应祥,等.肉牛日粮补锌对粗料纤维和玉米有机物瘤胃降解的影响[J].中国草食动物,2008,28(6):10-14.
[24]田丽娜,姜建阳,朱风华,等.纳米氧化锌对肉鸡生长性能和屠宰性能的影响[J].中国农学通报,2009,25(2):1-5.
[25]SPEARS J W, SCHLEGEL P, SEAL M C, et al. Bioavailability of zinc from zinc sulfate and different organic zinc sources and their effects on ruminal volatile fatty acid proportions[J]. Livestock Production Science, 2004, 90:211-217.
