断奶日龄和日粮营养水平对陕北白绒山羊小肠形态发育和消化酶活性的影响  

Effects of Weaning Age and Dietary Nutritional Levels on Intestinal Morphology and Activity of Digestive Enzymes in 6-Month-Old Shaanbei White Cashmere Goats

作　　者：曲星梅 薛复来 黄晓瑜 张宇[1] 邢晓楠 张恩平[1] QU XingMei;XUE FuLai;HUANG XiaoYu;ZHANG Yu;XING XiaoNan;ZHANG EnPing(College of Animal Science and Technology,Northwest A&F University,Yangling 712100,Shaanxi;Zhucheng Animal Husbandry and Veterinary Administration of Shandong Province,Zhucheng 262200,Shandong)

机构地区：[1]西北农林科技大学动物科技学院,陕西杨凌712100 [2]山东诸城市畜牧兽医管理局,山东诸城262200

出　　处：《中国农业科学》2019年第19期3460-3470,共11页Scientia Agricultura Sinica

基　　金：国家重点研发计划项目(2016YFD0500508);陕西省重点研发计划项目(2017TSCXL-NY-04-02);陕西省农业科技创新转化项目(NYKJ-2016-04)

摘　　要：【目的】研究断奶日龄和饲喂不同营养水平的日粮对6月龄陕北白绒羔羊小肠形态发育和小肠道主要消化酶活性的影响。间接阐明陕北白绒山羊最佳断奶日龄和饲养标准,为两年三胎体系中羔羊早期断奶和日粮配制提供一定的技术参数和理论依据。【方法】选取54日龄左右健康、体重相近((10.73±1.03)kg)的陕北白绒山羊羔羊54只,随机分为6组,每组3个重复,每个重复3只羊。试验Ⅰ、Ⅱ、Ⅲ组羔羊分别于90、75、60日龄断奶,断奶后饲喂标准日粮;试验Ⅳ、Ⅴ、Ⅵ组羔羊均于60日龄断奶,断奶后分别饲喂消化能和粗蛋白水平为标准日粮85%、115%、130%的试验日粮。试验羊饲喂至6月龄,试验期间测定羔羊体重和采食量。试验结束后,从每个重复中随机挑选1只羊进行屠宰(屠宰前未禁食),分别采集十二指肠中上部、空肠中段、回肠末端组织样品2 cm^2,制成石蜡切片观察小肠形态;采集小肠各段食糜用于测定其胰蛋白酶、糜蛋白酶、脂肪酶、麦芽糖酶、蔗糖酶和α-淀粉酶的活性。【结果】(1)断奶日龄影响4-6月龄羔羊生长,Ⅲ组羔羊平均日增重显著高于Ⅰ组(P<0.05)。(2)断奶日龄影响6月龄羔羊小肠的组织形态,十二指肠的肌层厚度和空肠绒毛表面积Ⅲ组显著高于Ⅰ和Ⅱ组(P<0.05);十二指肠绒毛宽度、回肠绒毛宽度Ⅱ、Ⅲ组显著高于Ⅰ组(P<0.05)。(3)断奶日龄影响小肠内消化酶的活性,十二指肠和回肠中脂肪酶活、空肠和回肠中的糜蛋白酶活性Ⅲ组显著高于Ⅰ和Ⅱ组(P<0.05)。(4)日粮营养水平影响小肠组织形态,十二指肠的绒毛高度、绒毛宽度、肌层厚度、绒毛表面积和空肠的绒毛高度、肌层厚度以及回肠的绒毛高度、V/C等指标Ⅴ和Ⅵ组显著高于Ⅲ组和Ⅳ组(P<0.01)。(5)日粮营养水平影响小肠内消化酶的活性,十二指肠中糜蛋白酶活、胰蛋白酶活性Ⅴ组和Ⅵ组显著高于Ⅲ组和Ⅳ组(P<0.0【Objective】This study aimed to investigate the effects of weaning age and dietary nutritional levels on intestinal morphology and activity of major digestive enzymes of 6-month-old Shaanbei white Cashmere goats.【Method】Fifty-four Shaanbei White Cashmere female goats aged 54 days(live body weight was(10.73±1.03)kg)were randomly assigned to 6 groups,with 3 replications per group and 3 goats per replication.Group I,Ⅱ,andⅢwere fed standard diets,and the weaning age was 90 d,75 d and 60 d,respectively.Goats in groupⅣ,V andⅥwere all weaned at 60 d,and were fed diet with 85%,115%,130%digestive energy and protein levels of the standard diets,resptectively.Goats were fed to 6-month-old.At the end of the trial period,1 goat were randomly selected from each replicate for slaughter(no fasting before slaughter),and 2 cm^2 tissue samples were collected from upper middle section of duodenum,middle jejunum and distal ileum,respectively.Paraffin sections of sampling tissues were made to observe the morphology of the small intestine.Chyme from each segment of the small intestine was collected for the determination of the enzymes activity of trypsin,chymotrypsin,lipase,alpha-amylase,sucrase and maltase.【Result】The results showed that:(1)Weaning age affected growth performance of lamb in 4-6 month.The lamb average daily gain of groupⅢwas significantly greater than that of groupⅠ(P<0.05).(2)Weaning age affected small intestine histological morphology of 6-month-old lambs.Muscular layer thickness of duodenum and villi surface area of jejunum of groupⅢwas significantly greater than that of groupⅠor groupⅡ(P<0.05);the villi width of duodenum and the villi width of ileum groupⅡand groupⅢwas significantly higher than that of groupⅠ(P<0.05).(3)weaning age affected the activity of digestive enzymes in small intestine.The activity of lipase in duodenum and ileum,the activity of chymotrypsin in jejunum and ileum,groupⅢwas significantly higher than that of groupⅠor groupⅡ(P<0.05).(4)Nutrient level of

关 键 词：陕北白绒山羊 营养水平 断奶日龄 小肠形态 消化酶活性 

分 类 号：S82[农业科学—畜牧学]