全混合日粮物理有效中性洗涤纤维水平对泌乳中期奶牛瘤胃液和乳中脂肪酸组成的影响  

Effects of Physically Effective Neutral Detergent Fiber Level in Total Mixed Ration on Fatty Acid Composition in Rumen Fluid and Milk of Dairy Cows during Mid-Lactation Period

作　　者：王砀砀 赵会会 肖凯丽 姚军虎[1] 曹阳春[1] WANG Dangdang;ZHAO Huihui;XIAO Kaili ;YAO Junhu;CAO Yangchun(College of Animal science and Technology,Northwest A&F University,Yangling 712100,China)

机构地区：[1]西北农林科技大学动物科技学院,杨凌712100

出　　处：《动物营养学报》2018年第7期2841-2849,共9页CHINESE JOURNAL OF ANIMAL NUTRITION

基　　金：国家自然科学基金(31402102);杨凌示范区产学研用协同创新重大项目(2016CXY-18)

摘　　要：本文旨在研究不同全混合日粮(TMR)物理有效中性洗涤纤维(peNDF)水平对泌乳中期奶牛瘤胃液和乳中脂肪酸组成的影响。选用30头体重约650 kg、2胎次、产后(120±8)d、日均产奶量(33.03±1.59)kg、体况相近的健康荷斯坦奶牛为试验动物,采用单因素试验设计,随机分为3组,通过控制搅拌时间获得低(9.02%)、中(10.56%)、高(11.25%)3个peNDF水平的TMR,每种TMR饲喂1组奶牛,每组10头。TMR精粗比为60∶40。预试期21 d,正试期6 d。结果表明:1)随着peNDF水平的提高,瘤胃液中肉豆蔻酸(C14∶0)、反9肉豆蔻烯酸(C14∶1trans9)、珍珠酸(C17∶0)、顺6油酸(C18∶1 cis6)含量降低,异棕榈酸(C16∶0 iso)、反9棕榈烯酸(C16∶1 trans9)含量上升,高peNDF组和低peNDF组差异显著(P<0.05)。2)随着peNDF水平的提高,乳中顺9肉豆蔻烯酸(C14∶1 cis9)、顺10十五烯酸(C15∶1 cis10)、顺10十七烯酸(C17∶1 cis10)、顺11油酸(C18∶1 cis11)、反9,12亚油酸(C18∶2 trans9,12)含量降低,异肉豆蔻酸(C14∶0 iso)、C16∶0 iso含量上升,高peNDF组和低peNDF组差异显著(P<0.05);随着peNDF水平的提高,乳中短链脂肪酸含量提高,肉豆蔻烯酸△9去饱和酶指数、油酸△9去饱和酶指数降低,高peNDF组和低peNDF组差异显著(P<0.05)。结果提示,在高精料条件下,泌乳中期奶牛饲喂低peNDF水平(9.02%)TMR可改善乳中脂肪酸组成。This study was conducted to investigate the effects of physically effective neutral detergent fiber(peNDF)level in total mixed ration(TMR)on fatty acid composition in rumen fluid and milk of dairy cows during mid-lactation period.Based on a single factor experiment design,thirty healthy dairy cows with two parities,(120±8)days in milk,(33.03±1.59)kg of average daily milk yield and similar body condition were chosen as trial individuals and randomly divided into 3 groups with 10 cows per group.Three TMRs with different levels of peNDF were obtained by manipulating the mixing duration(H-peNDF:11.25%,M-peNDF:10.56%,L-peNDF:9.02%),and each group was fed one of the three TMRs.The concentrate to forage ratio was 60∶40.The pretest period lasted for 21 days,and the test period lasted for 6 days.The results showed as follows:1)with the increase of peNDF level,C14∶0,C14∶1 trans9,C17∶0 and C18∶1 cis6 contents in rumen fluid were decreased,while C16∶0 iso and C16∶1 trans 9 contents in rumen fluid were increased,and there were significant differences between H-peNDF group and L-peNDF group(P<0.05).2)With the increase of peNDF level,C14∶1 cis9,C15∶1 cis10,C17∶1 cis10,C18∶1 cis11 and C18∶2 trans9,12 contents in milk were decreased,while C14∶0 iso and C16∶0 iso contents in milk were increased,and there were significant differences between H-peNDF group and L-peNDF group(P<0.05).With the increase of peNDF level,short chain fatty acid content in milk were increased,C14∶1 9-desaturase index and C18∶1 9-desaturase index were decreased,and there were significant differences between H-peNDF group and L-peNDF group(P<0.05).The results indicate that TMR with low level of peNDF(9.02%)can improve milk fatty acid composition under high concentrate condition.

关 键 词：物理有效中性洗涤纤维 瘤胃液 乳 脂肪酸组成 奶牛 

分 类 号：S823[农业科学—畜牧学]