不同棉秆水平对育肥期绵羊游离棉酚残留及日粮养分表观消化率的影响

Effects of Different Cotton Stalk Levels on Free Gosspol Content and DietaryNutrient Apparent Digestibility in Sheep During Fattening Period

试验旨在分析不同棉秆水平对育肥期绵羊游离棉酚残留及表观消化率的影响。采用单因素完全随机试验设计,将体重相近的60只小尾寒羊随机分为6组,每组10只,基于等能等氮原则配制试验日粮,其中对照1组(ck1)组不添加棉花秸秆和棉籽粕,对照2组(ck2)组添加棉籽粕,20%组、30%组、40%组和50%组分别添加20%~50%的棉秆。试验期70 d,其中预试期10 d,正试期60 d。于正试期第50天,分别在每组中随机选取3只羊,采用全收粪法收集24 h的粪样,适应期5 d,连续收集5 d,3 d称重并记录。正试期第55~60天记录每组试验羊的日饲喂量和剩料量,计算平均干物质采食量。结果显示,除ck1组外,20%组的游离棉酚残留量最低,与ck2组、30%组、40%组和50%组差异极显著(P<0.01)。小尾寒羊的干物质采食量、粗蛋白质、粗脂肪、钙、磷和灰分的表观消化率随棉秆添加比例的增加有上升趋势,但排粪量、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)表观消化率均无显著影响(P>0.05)。表明棉秆可作为粗饲料用于育肥羊生产,基于游离棉酚残留和表观消化率综合考虑棉秆添加量在20%时为宜。

This study was aimed to analyze the effects of different cotton stalk levels on free gosspol content and apparent digestibility in sheep during fattening period.Designed by single factor random test single factor randomized trial,the similar weight of 60 Small-tailed Han sheep were randomly divided into 6 groups,every group had 10 sheep.The diet was prepared for free feeding based on same energy and same nitrogen content.The control group ck1 did not add cotton stalks and cottonseed meal,the control group ck2 added cottonseed meal,and 20%to 50%cotton stalks were added to 20%,30%,40%and 50%groups,respectively,with a total period of 70 days,of which the pre-test period was 10 days and the feeding test was 60 days.On the 50th day of the trial period,the fecal samples were collected for 24 h using the full-fee method.The acclimation period was 5 days,and the samples were collected continuously for 5 days,weighed and recorded for 3 days.On the 55th to 60th day,the daily feeding amount and the remaining material amount of each group of test sheep were recorded,and the average dry matter intake was calculated.The results showed that expect for ck1 group,the 20%group had the lowest free gossypol residue,which was extremely significantly different from ck2,30%,40%and 50%groups(P<0.01).The apparent digestibility of dry matter,CP,EE,Ca,P and Ash increased with the increase in the proportion of cotton stalk.The addition ratio of 20%-50%had no significant effect on fecal output and the apparent digestibility of NDF and ADF(P>0.05).The results suggested that cotton stalk could be used as raw material for fattening sheep production,it was advisable to consider cotton stalk addition at about 20%which based on the data of free gosspol content and apparent digestibility.