不同留茬高度对全株玉米青贮营养成分、发酵品质、瘤胃降解率和奶牛生产性能的影响  

Effects of Different Stubble Heights on Nutrient Composition,Fermentation Quality,Rumen Degradation Rate and Dairy Cows,Performance of Whole-Plant Corn Silage

作　　者：任凯 孔凡林 季少雄 刘思源 吉虹锦 李祥浩 邵伟[1] 李胜利 REN Kai;KONG Fanlin;JI Shaoxiong;LIU Siyuan;JI Hongjin;LI Xianghao;SHAO Wei;LI Shengli(College of Animal Science,Xinjiang Agricultural University,Urumqi 830052,China;State Key Laboratory of Animal Nutrition and Feeding,College of Animal Science and Technology,China Agricultural University,Beijing 100193,China;College of Animal Science and Technology,Tarim University,Alar 843300,China)

机构地区：[1]新疆农业大学动物科学学院,乌鲁木齐830052 [2]中国农业大学动物科技学院,畜禽营养与饲养全国重点实验室,北京100193 [3]塔里木大学动物科学与技术学院,阿拉尔843300

出　　处：《动物营养学报》2024年第9期5722-5735,共14页CHINESE JOURNAL OF ANIMAL NUTRITION

基　　金：财政部和农业农村部-国家现代农业产业技术体系资助(CARS36);乌兰察布市关键技术攻关项目(2021GJ206)。

摘　　要：本试验旨在探究不同留茬高度对全株玉米青贮营养成分、发酵品质、瘤胃降解率和奶牛生产性能的影响。试验玉米品种选用“东科301”,采用单因素试验设计,在同一时间和地点对处于蜡熟期的全株玉米进行收割,3组留茬高度分别为20、30和40 cm,各留茬高度重复取样3次,对全株玉米青贮前后营养成分、发酵品质及营养物质降解率和降解参数进行测定;并选择45头泌乳奶牛,根据胎次(3胎)、泌乳天数[(44.8±5.0)d]、产奶量[(43.5±1.5)kg/d]和体况评分(3.5分)将其随机分为3组(每组15头),分别饲喂含有不同留茬高度(20、30和40 cm)全株玉米青贮的全混合日粮,预试期10 d,正试期60 d。结果显示:1)40 cm组全株玉米青贮前后中性洗涤纤维、酸性洗涤纤维含量显著低于20 cm组(P<0.05),淀粉、水溶性碳水化合物、非纤维性碳水化合物含量和相对饲喂价值显著高于20 cm组(P<0.05)。2)30 cm组和40 cm组全株玉米青贮的乙酸、丙酸和总挥发性脂肪酸含量显著高于20 cm组(P<0.05),丁酸含量显著低于20 cm组(P<0.05)。3)40 cm组全株玉米青贮的72 h干物质、中性洗涤纤维和酸性洗涤纤维降解率显著高于20 cm组(P<0.05),干物质、中性洗涤纤维、酸性洗涤纤维和淀粉有效降解率显著高于20 cm组(P<0.05)。4)40 cm组产奶量、4%乳脂校正乳、能量校正乳、饲料转化率及乳脂、乳蛋白含量显著高于20 cm组和30 cm组(P<0.05)。由此可见,提高全株玉米的留茬高度不仅提升了全株玉米青贮的营养价值、青贮品质和可消化物质含量,饲喂后还有助于提升奶牛产奶量和饲料转化率,增加牛奶中乳脂和乳蛋白含量,改善牛奶品质。本试验条件下,全株玉米的适宜留茬高度为40 cm。The aim of this experiment was to investigate the effects of different stubble heights on nutrient composition,fermentation quality,rumen degradation rate and dairy cows,performance of whole-plant corn silage.The experimental corn variety was“Dongke 301”,and a one-way experimental design was adopted,the whole-plant corn at the wax maturity stage was harvested at the same time and place,the stubble heights were set at 20,30 and 40 cm for three groups,respectively,and the sampling of stubble height was repeated for 3 times.The nutrient composition,fermentation quality and nutrient degradation rates and degradation parameters of whole-plant corn before and after silage were determined.Forty-five lactating dairy cows were selected and randomly divided into three groups(15 cows in each group)according to parity(3 parity),lactation days[(44.8±5.0)d],milk yield[(43.5±1.5)kg/d]and body condition score(3.5 score),and cows were fed total mixed rations which contained whole-plant corn silage with different stubble heights(20,30 and 40 cm),the pre-experimental period lasted for 10 days,and the experimental period lasted for 60 days.The results showed as follows:1)the contents of neutral detergent fiber and acid detergent fiber in whole-plant corn before and after silage of group 40 cm were significantly lower than those of group 20 cm(P<0.05),and the contents of starch,water-soluble carbohydrates and non-fibrous carbohydrates and relative feeding value were significantly higher than those of group 20 cm(P<0.05).2)The contents of acetic acid,propionic acid and total volatile fatty acids in whole-plant corn silage of group 30 cm and group 40 cm were significantly higher than those of group 20 cm(P<0.05),and the butyric acid content was significantly lower than that of group 20 cm(P<0.05).3)The 72 h degradation rates of dry matter,neutral detergent fiber and acid detergent fiber of whole-plant corn silage of group 40 cm were significantly higher than those of group 20 cm(P<0.05),and the effective degradation rates of dry

关 键 词：全株玉米 留茬高度 青贮 瘤胃降解率 生产性能 

分 类 号：S816.5[农业科学—饲料科学]