肉羊粪便形态与饲料养分消化率的关系研究

Relationship between Fecal Morphology and Nutrients Digestibility of Mutton Sheep

研究旨在探索肉羊粪便形态与粪便营养成分及饲料主要养分消化率的关系。选取年龄(4~5月龄)和体况(2.5~3.5分)相近的小尾寒羊268只,饲喂相同日粮,跟踪研究28 d。根据粪便形态设置6分制粪便评分表,各评分选取16只肉羊,通过直肠采粪法采集粪便样品,测定饲料和粪便中干物质(DM)、总能(GE)、粗蛋白(CP)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)和酸不溶灰分(AIA)含量,计算营养成分表观消化率。结果表明,不同粪便评分的肉羊粪便DM、GE、CP、NDF和AIA含量差异显著(P<0.05),ADF含量差异不显著(P>0.05)。随粪便评分的提高,粪便中DM和NDF含量线性下降(P<0.05),GE和CP含量呈先升高后降低的二次曲线变化(P<0.05),AIA含量呈先降低后升高的二次曲线变化(P<0.05)。粪便评分可显著影响DM、GE、CP、NDF和ADF的表观消化率(P<0.05)。随粪便评分的升高,各营养成分的表观消化率均呈先降低后升高的二次曲线变化(P<0.05)。该研究根据羊粪便的形态特征制定了羊粪便评分细则,并证实粪便评分对羊粪便营养成分含量以及营养成分表观消化率具有良好的指示作用。

The purpose of this study was to explore the relationship between fecal morphology and nutrient digestibility of sheep.A total of 268 Small Tail Han sheep with similar age(4-5 months)and body condition(2.5-3.5 points)were selected.All sheep were fed the same diet with free access to clean water.A 6-point fecal scoring criteria was set up according to the fecal morphology of sheep,and a follow-up study lasted for 28 days.Fecal samples were collected from 16 selected mutton sheep with each fecal score by rectal sampling method.Dry matter(DM),gross energy(GE),crude protein(CP),neutral detergent fiber(NDF),acid detergent fiber(ADF)and acid insoluble ash(AIA)in feed and faeces were determined,and apparent nutrient digestibility were determined by internal tagging method.The results showed that the contents of DM,GE,CP,NDF,ADF and AIA in faeces were significantly different among different fecal scores(P<0.05),but ADF was not affected(P>0.05).With the increase of fecal score,the contents of DM and NDF in faeces decreased linearly(P<0.05),the contents of GE and CP increased at lower fecal score and then decreased(P<0.05),and the content of AIA decreased at lower fecal score and then increased(P<0.05).Fecal score also significantly affected the apparent digestibility of DM,GE,CP,NDF and ADF(P<0.05).With the increase of fecal score,the apparent digestibility of all nutrients decreased at lower fecal score and then increased(P<0.05).This experiment formulates a fecal scoring criteria of sheep according to their fecal morphology,the results confirm that this fecal scoring criteria has a good indicative value on the fecal nutrient content and apparent digestibility of sheep.