营养水平对湖羊生长性能、血清生化指标、屠宰性能和肉品质的影响

Effects of different nutrition levels on growth performance,serum indexes,slaughter performance and meat traits of Hu lamb

[目的]本试验旨在探究不同营养(能量和蛋白)水平日粮对湖羊生长性能、血清生化指标、屠宰性能和肉品质的影响。[方法]选择40只体质量为(18.35±1.39)kg的湖羊公羔,随机分为4组,每组10只。设计4种日粮水平饲喂湖羊公羔,分别为对照组(代谢能8.40 MJ·kg^(-1),粗蛋白12.84%),高蛋白(HP)组(代谢能8.68 MJ·kg^(-1),粗蛋白15.33%),高能量(HE)组(代谢能9.70 MJ·kg^(-1),粗蛋白13.05%)和高能、高蛋白(HEP)组(代谢能9.66 MJ·kg^(-1),粗蛋白15.44%)。试验期60 d。在试验开始和结束时测定羔羊日增质量(ADG)、平均采食量(ADFI)和料重比(F/G)等生长性能指标,并采集血液样品分析总蛋白(TP)、白蛋白(ALB)、球蛋白(GLO)、尿素氮(BUN)、血糖(GLU)和甘油三酯(TG)等血清生化指标,同时在试验结束时进行屠宰试验,测定活体、胴体、血液、头、蹄、皮毛、内脏及消化道质量等屠宰性能以及p H值、失水率和熟肉率等肉品质指标。[结果]3个试验组(HP、HE和HEP)的终末体质量和ADG均显著高于对照组(P<0.05);F/G的变化规律为对照组显著高于HP组,HEP组显著高于HE组(P<0.05)。血清TP含量从大到小依次为HEP组、HP组、HE组和对照组,BUN浓度从高到低为HP组、HEP组、HE组和对照组,差异显著(P<0.05);HE组的GLU和TG浓度显著高于其他3组(P<0.05)。3个试验组宰前活质量和胴体质量显著高于对照组(P<0.05);HE组和HEP组的屠宰率和眼肌面积显著大于其他2组(P<0.05);与对照组相比,3个试验组的头、蹄、皮毛、心脏、肝、肾和小肠的质量有增长趋势(P>0.05);HP组瘤胃质量显著高于其他3组(P<0.05)。3个试验组失水率显著低于对照组(P<0.05)。[结论]提高日粮营养水平可改善湖羊公羔生长性能、屠宰性能与肉品质,并对血清中与蛋白代谢或能量代谢的相关指标产生影响;高能量水平日粮在湖羊公羔育肥阶段发挥更重要的作用。

[ Objectives ] The current study was performed to investigate the effects of different dietary nutrition levels on growth performance,serum indexes,slaughter performance and meat traits of Hu lamb. [ Methods] Forty Hu lambs with similar body weight（ 18.35±1.39） kg were randomly divided into four groups, which were then denoted as control group（ containing 8.40 MJ·kg^-1 metabolic energy and 12.84% crude protein）, high protein （HP）group （containing 8.68 MJ·kg^-1 metabolic energy and 15.33% crude protein）, high energy（HE） group（ containing 9.70 MJ·kg^-1 metabolic energy and 13.05% crude protein）, and high protein and high energy （HEP） group（containing 9.66 MJ·kg^-1 metabolic energy and 15.44% crude protein）. The experiment lasted for 60 d. The growth performance [ average daily gain （ADG）, feed intake （ ADFI ） and feed to gain ratio （F/G） ], blood biochemistry index [ total protein （ TP ）, albumin （ ALB）, globin （GLO）, ureanitrogen （BUN）, blood glucose （GLU） and triglyceride （TG） ] were determined after feeding for 60 days and three lambs of each group were killed to measure slaughter performance （ alive weight, the weight of carcass, blood, heads, hoofs, fur, internal organs and digestive tract）and meat quality （pH, water loss rate and the rate of cooked meat）. [ Results ] The results showed that the final weight and ADG in the three experimental groups （HP, HE and HEP groups）were significantly higher than the control group （P〈0.05）, and F/G in the control group was significantly higher than the HP group, and HEP group was significantly higher than the HE group. The serum TP concentration in a descending order was：HEP, HP, HE and control group（ P〈0.05 ） ;BUN concentration in a descending order was ：HP ,HEP ,HE and control group（P〈0.05）. The concentration of GLU and TG in the HE group were signifi- cantly higher than the three experimental groups （P〈0.05）. The living weight and carcass weight in the three experimental group were significantly higher than the control groups（P〈0.05）. The dressing percentage and eye muscle area in the HE and HEP groups were significantly higher than other two groups （P〈0.05）. Compared with control group, the wight of head, feet, fur, heart, liver, kidney and intestine had trend of growth in the three expremental groups, but no significant difference （P〉0.05）. The rumen weight in the HP group was significantly higher than the three experimental groups（P〈0.05）. The drip loss in the three experimental groups was significantly lower than the control group（P〈0.05）. [ Conclusions ] In conclusion, the improvement of dietary nutrition levels can significantly increase the growth rate, slaughter performance and meat traits of Hu lamb,and have an effects on the related indicators of protein metabolism or energy metabolism in blood. And high energy levels of diet play an important role in fattening penod of Hu lamb.