华苎5号苎麻嫩茎叶营养成分及其在山羊瘤胃中的降解特性

A study of nutritional components in tender leaves and stems of Huazhu No.5 Ramie and degradation characteristics in goat rumen

本研究利用化学分析法评价华苎5号苎麻(Boehmeria nivea)不同茬次的营养成分,选取3只健康装有永久瘤胃瘘管的波尔山羊,采用尼龙袋法测定第1、4、7茬次的苎麻嫩茎叶营养成分在瘤胃中的降解特性,旨在评价苎麻的营养价值,为苎麻在反刍动物中的牧草化利用提供数据参考。结果表明,1)华苎5号苎麻7个茬次嫩茎叶粗蛋白质(crude protein,CP)和粗脂肪(ether extract,EEE)含量随着收获茬次的增加先上升后下降,CP平均含量22.84%,16种氨基酸含量占CP总量的74.21%,赖氨酸平均含量为0.88%,钙平均含量达到4.95%,而钙磷比平均达到12.88。苎麻嫩茎叶干物质采食量、可消化干物质和相对饲喂价值都呈现出随茬次增加先上升后下降的规律。2)苎麻嫩茎叶CP、中性洗涤纤维(neutral detergent fiber,NDF)和酸性洗涤纤维(acid detergent fiber,DF)的72 h瘤胃降解率第7茬>第1茬>第4茬。3个茬次苎麻嫩茎叶的干物质(dry matter,DM)、CP、有机物(organic matter,OM)、NDF和ADF 72 h瘤胃降解率和有效降解率的高低顺序基本一致。本研究结果显示,华苎5号苎麻嫩茎叶的粗蛋白质含量高,氨基酸含量丰富,纤维物质含量适中,第1、7茬营养成分DM、CP、OM、NDF、ADF在瘤胃中的降解率均较高,可作为草食动物的高蛋白质饲草来源。

In this study,the nutritional components of Huazhu No.5 ramie tender stems and leaves in different crops was evaluated,and the rumen degradation characteristics of the ramie tender stems and leaves of the first,fourth,and seventh crops were determined using the nylon bag method in three healthy Boer goats with permanent rumen fistulas.The purpose of this study was to evaluate the nutritional value of ramie and provide a data reference for the forage utilization of ramie in ruminants.The results showed that:1)the content of crude protein(CP)and ether extract(EE)of seven stubble ramie tender stems and leaves of Huazhu No.5 ramie first increased and then decreased with the increase in the harvest stubble.The average CP content was 22.84%,and the content of 16 amino acids accounted for 74.21%of the total protein;the average lysine content,calcium content,and calcium-phosphorus ratio was 0.88%,4.95%,and 12.88,respectively.The dry matter intake,digestible dry matter,and relative feeding value of ramie tender stems and leaves all showed a pattern of first increase and then decrease with the increase in stubble.2)The rumen degradation rate of CP,neutral detergent fiber(NDF),and acid detergent fiber(ADF)in ramie tender stems and leaves for 72 h showed a consistent rule,i.e.,the seventh crop>the first crop>the fourth crop.The dry matter(DM),CP,organic matter(OM),NDF,and ADF of the ramie tender stems and leaves of the three stubbles were basically in the same order of rumen degradation rate value and effective degradation rate value at 72 h.The results show that the degradation rates of DM,CP,OM,NDF,and ADF in the rumen of the first and seventh seasons are high.Ramie can be used as a source of high protein forage for herbivores.