收获时间与留茬高度对桂青贮7号青贮玉米体外消化特性的影响  

Effects of Harvest Time and Stubble Height on in Vitro Digestive Characteristics of Gui Silage No.7 Silage Maize

作　　者：何晓琳 王胜男 肖艺梅 尹福泉[1] 卢艳丽 HE Xiaolin;WANG Shengnan;XIAO Yimei;YIN Fuquan;LU Yanli(College of Coastal Agricultural Sciences,Guangdong Ocean University,Zhanjiang 524088,China)

机构地区：[1]广东海洋大学滨海农学院,湛江524088

出　　处：《动物营养学报》2024年第2期1315-1330,共16页CHINESE JOURNAL OF ANIMAL NUTRITION

基　　金：广东省2021年“大专项+项目清单”项目——粤西地区全株青贮玉米种质资源引进、高效生产及饲用价值研究(2021A05209);广东海洋大学乡村振兴“揭榜挂帅”科技帮扶项目——雷州山羊育繁推一体化关键养殖技术创新集成与示范(04号);广东海洋大学2022年社会服务专项资金项目——遂溪县城月镇肉羊健康养殖技术示范与推广。

摘　　要：本试验旨在探究收获时间与留茬高度对桂青贮7号青贮玉米体外消化特性的影响。以桂青贮7号青贮玉米作为试验材料,分别于1/4乳线期、1/2乳线期、3/4乳线期及蜡熟期这4个收获时间以20、30、40、50、60 cm 5个留茬高度进行收割,之后采用青贮罐方法进行青贮,90 d后测定其常规营养成分含量和体外消化特性。结果表明:1)收获时间与留茬高度对青贮玉米中粗脂肪(EE)、钙(Ca)和磷(P)含量均无显著影响(P>0.05);青贮玉米中中性洗涤纤维(NDF)含量随收获时间的延后先下降后回升,随留茬高度的增高而下降,干物质(DM)含量随收获时间的延后而增加;在1/4乳线期收获,留茬高度为30 cm时粗蛋白质(CP)含量显著高于其他留茬高度(P<0.05),留茬高度为40 cm时酸性洗涤纤维(ADF)含量显著高于其他留茬高度(P<0.05);在1/2乳线期收获,留茬高度为40 cm时粗灰分(Ash)含量显著高于留茬高度为20、30、60 cm时(P<0.05);在3/4乳线期收获,留茬高度为30 cm时CP含量显著低于留茬高度为40、50、60 cm时(P<0.05)。2)收获时间与留茬高度对青贮玉米体外发酵3、6、12、24、48 h的产气量、氨态氮浓度和pH以及3、6、24、48 h的干物质降解率无显著影响(P>0.05)。在1/2乳线期收获,留茬高度为40 cm时青贮玉米体外发酵24 h的乙酸(AA)、丙酸(PA)、丁酸(BA)浓度及体外发酵48 h的AA、PA浓度最高,显著高于其他留茬高度(P<0.05);在3/4乳线期收获,留茬高度为50 cm时青贮玉米体外发酵24 h的AA、PA浓度最高,显著高于其他留茬高度(P<0.05)。综上所述,桂青贮7号青贮玉米的适宜收获时间为1/2乳线期,留茬高度为20~40 cm。This study aimed to explore the effects of harvest time and stubble height on the in vitro digestive characteristics of Gui silage No.7 silage maize.Using Gui silage No.7 silage maize as the test materials,and they were harvested at 5 stubble heights of 20,30,40,50,60 cm at 4 harvest times of 1/4 milk stage,1/2 milk stage,3/4 milk stage and dough stage,respectively.After that,the silage was carried out by the method of silage tank.After 90 days,the routine nutritional component contents and in vitro digestive characteristics were determined.The results showed as follows:1)harvest time and stubble height had no significant effects on the contents of ether extract(EE),calcium(Ca)and phosphorus(P)in silage maize(P>0.05);the content of neutral washing fiber(NDF)in silage maize decreased firstly and then increased with the delay of harvest time,and decreased with the increase of stubble height;dry matter(DM)content in silage maize increased with the delay of harvest time.When harvested at 1/4 milk stage,the crude protein(CP)content was significantly higher at 30 cm stubble height than other stubble heights(P<0.05),and the acid detergent fiber(ADF)content was significantly higher at 40 cm stubble height than other stubble heights(P<0.05);when harvested at 1/2 milk stage,the crude ash(Ash)content was significantly higher at 40 cm stubble height than 20,30 and 60 cm stubble heights(P<0.05);when harvested at 3/4 milk stage,the CP content was significantly higher at 30 cm stubble height than 40,50 and 60 cm stubble heights(P<0.05).2)The gas production,ammonia nitrogen concentration and pH of in vitro fermentation 3,6,12,24 and 48 h and dry matter degradation rate of in vitro fermentation 3,6,12 and 48 h did not significantly affect by the stubble height and harvest time(P>0.05).When harvested at 1/2 milk stage,the concentrations of acetic acid(AA),propionic acid(PA),butyric acid(BA)for 24 h in vitro fermentation and the concentrations of AA and PA for 48 h in vitro fermentation were the highest when the stubble height was

关 键 词：收割时间 留茬高度 玉米青贮 体外发酵 

分 类 号：S816[农业科学—饲料科学]