农户养殖模式下育肥羊瘤胃食糜外流速度及棉籽壳有效降解率的评定  

Measurement of rumen digesta passage rate and effective degradation of cottonseed hull in rumen of finishing lambs under the rural household feeding conditions

作　　者：刘晨黎[1] 赵伟利[1] 何佳文[1] 孔平[1] 刘保仓[1] 陈傲东[1] 高巍[1] 

机构地区：[1]石河子大学动物科技学院,新疆石河子832003

出　　处：《饲料工业》2014年第3期47-50,共4页Feed Industry

基　　金：国家自然科学基金项目[31260557];兵团博士资金专项[2013BB018]

摘　　要：棉籽壳是我区广大农户在育肥羊生产上大量使用的一种资源丰富的农副产物饲料，适口性好，同时由于缺乏优质粗饲料如苜蓿干草或玉米青贮，往往饲喂量过大，在冬春季甚至是唯一的粗饲料，常常引发尿结石，给农户带来经济损失。为了能更加科学有效地利用好这一地方饲料资源，文章对农户饲养条件下的育肥羊瘤胃食糜外流速度及棉籽壳DM、OM及CP的有效降解率进行了评定：以安装有永久性瘤胃瘘管的平均体重28kg的育肥哈萨克羊3只作为试验动物，代谢笼内单笼饲喂。每天饲喂棉籽壳200g，精料500g，小麦秸自由采食量约400～500g，余料不超过10％。早晚等量饲喂两次，自由饮水。采用小麦秸Cr—NDF作为固相食糜标记物，于晨饲前由瘤胃瘘管一次性灌注，每只羊40g。灌注后8～120h内采集不同时间点粪样。采样结束1周后，每只羊由瘤胃瘘管一次性灌注Cr—EDTA溶液150ml、采集灌注后0～48h不同时间点的瘤胃液。测定粪样及瘤胃液中的Cr浓度，计算固相和液相食糜的外流速度。采用尼龙袋技术评定棉籽壳DM、OM及CP的降解动力学参数，计算有效降解率及瘤胃停留时间。结果表明，瘤胃固相食糜的平均外流速度为1．84％／h，液相食糜外流速度为12.33％／h，DM、OM及CP的有效降解率分别为46．37％、46．00％和52．88％。在瘤胃内停留时间接近30h。研究为评定棉籽壳养分的小肠消化率提供了重要参数。Cottonseed hull, one of local abundant agricultural by-product feed resources in Xinjiang, is extensively used for sheep feeding in cotton planting area by farmers. However, for lack of high quality for-age such as alfalfa hay or corn silage under the rural household feeding conditions, and also its good palat-ability for sheep, cottonseed hull is usually extensively fed to lambs as solely fibrous forage in winter. However, great economic loss was usually brought about by urinary calculus caused by overfeeding of cot-tonseed hull in winter and spring season. In order to scientifically feeding and to improve the utilization ef- ficiency of cottonseed hull for lamb production, we conducted this experiment to measure the rumen diges-ta passage rate and effective degradation of DM, OM, and CP in cottonseed hull in rumen of finishing lambs under the rural household feeding conditions. Three rumen eannulated Kazakh wethers weighed in average 28 kg body weight were housed in meta-bolic crate singly. The daily diet was composed of cottonseed hull 200 g, concentrate supplement 500 g, wheat straw was fed ad libitum. The daily in-take was about 400-500 g and the daily refusals were less than 10%. The animals were fed twice daily in equal parts of daily diet, and ad libitum for water. The chromium mordant wheat straw NDF and Cr-EDTA solution were used as the solid or liquid digesta marker separately. Each animal was pulse dosed 40 g Cr-NDF through rumen fistula prior to morning feeding. After one week, 150 ml ufCr-EDTA solu-tion was flooding dosed through rumen fistula just prior to morning feeding for each lamb. The fecal samples af- ter dosing 8 h till 120 h, and also the rumen liquid samples after dnse 0-48 h period were collected for measur-ing the Cr concentration to calculate the rumen solid anti liquid digesla passage rate. The effective degradation rates ofDM, OM, anti CP in cottonseed hull as well as rumen retention time of cottonseed hull were investigat-ed by the standard nylon bag

关 键 词：棉籽壳 瘤胃 外流速度 有效降解率 育肥羊 

分 类 号：S816.32[农业科学—饲料科学]