硒和维生素E对氧化应激肉鸡生长性能和肉品质的影响

Effects of Dietary Selenium and Vitamin E on Growth Performance and Meat Quality of Oxidative Stressed Broilers

试验旨在评估添加硒和维生素E对氧化应激肉鸡生长性能和肉品质影响。选用1日龄Cobb500肉鸡雏200只,随机分为4个处理。处理1饲喂玉米-豆粕型基础日粮,处理2、3、4分别在基础日粮中添加Se0.20mg/kg、VE200mg/kg、Se0.20mg/kg+VE200mg/kg。从16日龄开始,每处理随机分为两组,一组腹部皮下注射Dexamethasone(DEX)3mg/kg体重,隔日注射三次(16、18、20日龄),另一组注射等量生理盐水。结果显示:氧化应激极显著降低了肉鸡日采食量和日增重(P<0.01),添加VE显著提高了氧化应激肉鸡日增重(P<0.05),而添加Se略有提高(P>0.05);氧化应激显著降低了宰后45min和24h肌肉pH值(P<0.05),添加Se和VE有提高氧化应激肉鸡胸肌pH值的趋势(P>0.05);氧化应激显著降低肌肉系水力(P<0.05),而添加Se可显著提高氧化应激肉鸡的肌肉系水力(P<0.05),添加VE有提高氧化应激肉鸡系水力的趋势(P>0.05)。氧化应激对肉鸡后期(22~42日龄)生产性能、屠宰性能及肉品质无显著影响(P>0.05)。研究结果揭示DEX诱导的氧化应激会导致鸡生长性能及肉品质显著降低,在日粮中添加硒和维生素E能在一定程度上缓解氧化应激的影响。

This experiment was conducted to evaluate effects of dietary selenium and vitamin E on growth performance and meat quality in broilers exposed to DEX-induced oxidative stress. A total of 200 one-day-age Cobb 500 broilers were randomly divided into four treatments. The first treatment was fed with corn-soybean meal basal diet, while the residual treatments were fed with the basal diet supplemented with 0.2 mg/kg selenium, 200 mg/kg vitamin E, or 0.2 mg/kg selenium+200 mg/kg vitamin E, respectively. All the treatments were randomly divided into two groups at 16 days of age. Subsequently, one group was injected subcutaneously at abdomen with Dexamethasone (DEX) at dosage of 3 mg/kg BW for 3 times every other day, while the other group was injected with saline and served as control. The results showed that average daily feed intake and daily gain were very significantly suppressed when birds were subjected to oxidative stress (P<0.01). Dietary vitamin E significantly enhanced daily gain of oxidative stressed broilers (P<0.05), while dietary selenium slightly increased daily gain (P>0.05). Oxidative stress significantly reduced pH value of breast muscle at 45 min and 24 h after slaughter (P<0.05). Moreover, the addition of selenium and vitamin E had a tendency to increase pH value of breast muscle in oxidative stress broilers(P>0.05).Oxidative stress significantly decreased muscle water-holding capacity(P<0.05), while dietary selenium significantly increased muscle water-holding capacity in oxidative stressed broilers (P<0.05), as well as dietary vitamin E slightly increased (P>0.05). In addition, oxidative stress had no significant influence on growth performance on 22 to 42 days, slaughter parameters (42 days of age) and meat quality (42 days of age) of broilers (P>0.05). The results suggested that growth performance and meat quality were significantly declined when broilers suffered from oxidative stress induced by DEX, dietary selenium and vitamin E could alleviate the negative impacts of oxidative stress to some extent.