动物营养学报2016，Vol.28Issue(6)：1696-1703,8.DOI:10.3969/j.issn.1006-267x.2016.06.009
热应激条件下粗饲料组合对奶牛氮素利用的影响
Effects of Forage Combinations on Nitrogen Efficiency of Dairy Cows under Heat Stress
摘要
Abstract
In order to investigate the effects of forage combinations on nitrogen efficiency of heat-stressed cows,twenty healthy Holstein cows with similar parities and days in milk were randomly divided into two groups with ten cows per group.Cows were fed diets with two forage combinations [corn silage+alfalfa hay (0.92∶1.00,AF group) and corn straw (CS group)],but with the same concentrate and the same concentrate to forage ratio (63.7∶36.3).The pretest lasted for 1 week,and the test lasted for 8 weeks.The results showed as follows:1) compared with CS group,cows in AF group had significantly higher milk,energy-corrected milk,4％ fat-corrected milk,milk protein and lactose yield (P＜0.05 or P＜0.01).2) Cows showed significantly higher crude protein (CP) apparent digestibility in AF group diet than that in CS group diet (P＜0.01).3) Ruminal microbial protein yield in AF group was significantly higher than that in CS group (P＜0.05),however,urine and blood urea nitrogen concentration were significantly lower in AF group (P＜0.01).4) Compared with CS group,cows in AF group had significantly higher nitrogen intake and milk nitrogen yield (P＜0.01),however,had significantly lower nitrogen conversion rate (P＜0.05).These results indicate that compared with corn straw,the combination of alfalfa hay and corn silage can increase dietary CP level,increase CP apparent digestibility,and improve microbial protein and milk protein synthesis of heat-stressed dairy cow,however,nitrogen efficiency needs to improve.关键词
热应激/粗饲料/微生物蛋白/表观消化率/氮转化效率Key words
heat stress/forage/microbial protein/apparent digestibility/nitrogen efficiency分类
农业科技引用本文复制引用
郭江,王加启,高胜涛,权素玉,卜登攀..热应激条件下粗饲料组合对奶牛氮素利用的影响[J].动物营养学报,2016,28(6):1696-1703,8.基金项目
国家自然科学基金(31372341) （31372341）
“十二五”国家科技支撑计划(2012BAD12B02-05) （2012BAD12B02-05）
中国农业科学院科技创新工程(ASTIP-IAS07) （ASTIP-IAS07）
