不同免疫应激对肉仔鸡生长性能、养分消化和肉品质的影响

Effects of Different Immune Stress on Growth Performance,Nutrient Digestibility and Meat Quality of Broilers

本试验旨在研究不同免疫应激对肉仔鸡生长性能、养分消化、血清生化指标和肉品质的影响。选取540只1日龄Cobb500肉仔鸡,随机分为5组(对照组、常免组、简免组、免疫亢进组和免疫抑制组),每组设9个重复,每个重复12只鸡。常免组和简免组按试验要求进行疫苗免疫,亢进组和抑制组在常免基础上分别注射细菌脂多糖(LPS)和环磷酰胺(CPM)。21日龄和42日龄屠宰取样,检测相关指标。结果表明:1)不同免疫应激对肉仔鸡料重比无显著差异(P>0.05);无免组和简免组肉仔鸡采食量和体增重与常免组无显著差异(P>0.05),LPS亢进和CPM抑制均极显著降低肉仔鸡全期体增重(P<0.01),且LPS亢进显著降低肉仔鸡全期采食量(P<0.05);2)不同免疫应激对能量表观消化率无显著差异(P>0.05);除简免组干物质表观消化率与无免组差异不显著(P>0.05)外,不同免疫应激均极显著或显著降低了肉仔鸡中后期干物质表观消化率(P<0.01)和粗脂肪表观消化率(P<0.05);肉仔鸡中后期免疫抑制组粗蛋白质回肠表观消化率显著降低(P<0.05);3)CPM抑制极显著增大了肌肉滴水损失(P<0.01)。结果提示:合理控制饲养环境条件下,无免疫不影响肉仔鸡生长性能,而免疫应激降低肉仔鸡对饲粮干物质、回肠粗蛋白质、粗脂肪的表观消化率,影响采食量和体增重,不利于肉仔鸡生长和生产。

The experiment was conducted to determine the effects of different immune stress on growth performance,nutrient digestibility,serum biochemical parameters and meat quality of broilers.Five hundred and forty Cobb500 broilers aged 1 day were randomly assigned to 5 groups [group 1： control group without experimental stress,group 2： stress from simplified vaccination,group 3： stress from general vaccination,group 4： stress from lipopolysaccharide（LPS） injection and general vaccination,group 5： stress from cyclophosphamide（CPM） injection and general vaccination] with 9 replicates per group and 12 birds per replicate.Broilers were killed and samples were collected to measure some parameters on d 21 and 42.The results showed as follows： ratio of feed to gain and apparent digestibility of energy had no significant difference among 5 groups（P0.05）.There were no significant differences in feed intake and body weight gain between groups 1 and 2 and group 3（P0.05）.Body weight gain of broilers in the whole period（d 1 to 42） was significantly decreased by LPS stress（group 4） and CPM stress（group 5）（P0.01）,and feed intake was significantly decreased by LPS stress（P0.05）.Different immune stress significantly decreased the apparent digestibility of dry matter（P0.01） and crude fat（P0.05） in broilers on d 22 to 42,except that the apparent digestibility of dry matter in group 3 had no significant difference with that in group 1（P0.05）.Crude protein apparent digestibility in ileal of broilers on d 22 to 42 was significantly decreased by CPM stess（P0.05）,and the drip loss was significantly increased by CPM stess（P0.01）.In conclusion,there are no adverse effects on growth performance of broilers without vaccination in the condition of rational feeding environment.However,immune stress decreases the apparent digestibility of dry matter,crude fat,ileal crude protein,feed intake and body weight gain,and it is adverse to the performance of broilers.