作 者：
王震;马铁伟;邓凯平;冯旭;李奉哲;王锋;陶晓强;樊懿萱
关键词：
湖羊;能量限饲;补偿生长;生长性能;血清生长类激素;肉品质
摘 要：
[目的]本试验旨在探索能量限饲和补偿对湖羊生长性能、血液生长相关激素和背最长肌肉品质的影响。[方法]选取90日龄体质量为(22.02±0.14)kg健康湖羊公羔80只,随机分为4组:对照组(EC)、85%能量组(EG1)、70%能量组(EG2)和55%能量组(EG3)。限饲2个月,其日粮能量水平分别为11.63、9.73、8.40和6.84 MJ·kg-1。补偿期3个月,日粮能量水平均为12.44 MJ·kg-1。试验期间羔羊每个月称质量,采取颈静脉血测定血清激素水平,在限饲和补饲结束时分别屠宰采取背最长肌样进行肉品质鉴定。[结果]限饲结束后,EG1、EG2和EG3组体质量和日增重显著低于EC组(P<0.05)。补饲后,限饲组体质量与对照组相近(P<0.05)。限饲结束,随着限饲水平提高,血液生长激素(GH)水平升高(P<0.05),而胰岛素样生长因子1(IGF-1)水平逐渐降低(P<0.05)。补饲后,EG2和EG3组的GH浓度显著高于EC和EG1组(P<0.05),而各组IGF-1水平相近(P>0.05)。限饲后,EG3组背最长肌的pH值、pH24 h值和滴水损失均高于EC和EG1组(P<0.05);EG2和EG3组背最长肌粗蛋白含量显著高于EC组(P<0.05),而粗脂肪含量却低于EC组(P<0.05);眼肌面积和肌纤维横截面积均随限饲水平增大而逐渐减小(P<0.01);EG2和EG3组肌纤维密度极显著高于EC和EG1组(P<0.01)。补饲后,EG1组背最长肌失水率高于EC和EG3组(P<0.05);EG2组肌纤维横截面积高于EC和EG1组(P<0.01)。[结论]能量限饲会降低羔羊体质量,提高血液GH水平,降低血液IGF-1水平,提高背肌蛋白比例,增加肌纤维密度,进而改善肉质。补偿生长后,血液GH保持高浓度,生长性能虽能恢复正常水平,但肉品质相对变差。85%能量限饲后偿效果最好。
译 名：
Effects of energy restriction and compensation on growth performance,and related hormones and meat quality of Hu sheep
作 者：
WANG Zhen;MA Tiewei;DENG Kaiping;FENG Xu;LI Fengzhe;WANG Feng;TAO Xiaoqiang;FAN Yixuan;Jiangsu Engineering Technology Research Center of Meat Sheep & Goat Industry,Nanjing Agricultural University;Jiangsu Taizhou Helen Sheep Industry Co.,Ltd.;
关键词：
Hu sheep;;energy restriction;;compensation growth;;growth performance;;serum growth-related hormone;;meat quality
摘 要：
[Objectives]This study aims to investigate the effect of energy restriction and compensation on growth performance,related hormones and meat quality of Hu sheep. [Methods]Eighty male 90-day-old-sheep with(22.02±0.14) kg body weight were randomly distributed into four treatments: energy control group(EC),85% energy group(EG1),70% energy group(EG2) and 55% energy group(EG3). Dietary energy levels of restriction feeding period were 11.63,9.73,8.40 and 6.84 MJ·kg-1,respectively and all were12.44 MJ·kg-1 in compensatory period. Lambs were weighted and the jugular venous blood was collected to measure the serum hormones in each month. Longissimus dorsi was sampled to detect the meat quality at the end of restriction feeding and compensation.[Results]The results indicated that after restriction feeding,the body weight and daily gain were lower in EG1,EG2 and EG3 group than in EC group(P < 0. 05),however,the body weight of restriction group was similar with the control group after compensation feeding(P>0.05). With the increase of the restricted feeding level,the serum growth hormone(GH) level of Hu sheep increased(P<0.05) while the insulin-like growth factor-1(IGF-1) density decreased after restriction feeding(P<0.05). After compensatory feeding,the serum GH level was higher in EG2 and EG3 than that in EC and EG1(P<0.05),however,the IGF-1 level was similar in each group(P>0.05). After restriction feeding,the pH,pH24 hand drip loss of longissimus dorsi were higher in EG3 compared with EC and EG1(P<0.05); the CP content of longissimus dorsi was higher in EG2 and EG3 than that in EC(P < 0. 05),but the etherextract content was lower(P < 0. 05); the eye muscle area and the cross-sectional area of muscle fiber were all smaller with the increase of the restriction feeding level; the muscle fiber density was extremely higher in EG2 and EG3 than that in EC and EG1(P<0.01). After compensation feeding,the water loss rate was higher in EG1 than that in EC and EG3(P<0.05); the muscle fiber cross-sectional area was extremely higher in EG2 than that in EC and EG1(P< 0.01). [Conclusions]Energy restriction can reduce the weight of lambs,increase GH concentration in blood,reduce IGF-1 concentration in blood,increase the protein proportion of dorsal muscle,increase muscle fiber density and thereby improve the meat quality. After the growth of compensation,the GH concentration in blood keeps in high level. Although the growth performance can return to normal levels,the meat quality is relatively poor,and among all groups the 85% energy feeding group obtains the best compensatory result.
