宰前免疫应激对肉鸡抗氧化性能与肉品质的影响

 研究旨在探讨细菌脂多糖(1ipopolysaccharide，LPS)诱导的宰前免疫应激对肉鸡抗氧化性能和肉品质的影响。24只体重相近的39 d肉仔鸡随机分为3组， 两个试验组分别在39 d、40 d和41 d腹部皮下注射LPS生理盐水稀释液(1 000和2 000 μg/kg BW)，对照组注射等量生理盐水。结果表明，与对照组相比，胸肌pH24h极显著下降（P<0.01），失水率极显著增高（P<0.01），4 ℃保存3 d b*值和6 d的L*值显著升高（P<0.05）；腿肌pH45min及pH24h均极显著下降（P<0.01），4 ℃保存3 d b*值显著升高（P<0.05）；血浆、胸肌和腿肌MDA含量均显著升高（P<0.05），血浆T AOC极显著降低（P<0.01）。本研究表明宰前免疫应激会引起肉鸡机体氧化损伤和抗氧化机能下降，进而导致肉鸡生长性能和肉品质显著下降，而且这些负面效应的大小取决于应激强度。

Effect of Preslaughter Immunological Stress on Antioxidant Capacity and Meat Quality of Broilers

This study aimed to investigate effects of preslaughter immunological stress induced by lipopolysaccharide (LPS) on antioxidant capacity and meat quality of broilers. Twenty four broilers (39 day old) with similar body weight (BW) were randomly assigned to three treatments: sham injection of saline (control), daily subcutaneous (s.c.) injection of LPS (1 000 μg/kg and 2 000 μg/kg of BW) for 3 days. The results showed that average daily feed intake and BW of chickens significantly decreased in the LPS treatment (P<0.05). The F/G significantly enhanced (P<0.01). PH 24 h of breast muscle significantly decreased (P<0.05), water loss rate of breast muscle increased remarkably (P<0.01). Yellowness (b*) on the 3rd day and lightness (L*) on the 6th day of breast muscle stored at 4 ℃ improved siginificantly (P<0.05). PH45min and PH 24 h of thigh muscle decreased significantly in the LPS treatment (P<0.01). Redness (a*) of thigh muscle stored at 4 ℃ for 3 days significantly increased (P<0.05). The plasma, MDA of breast and thigh muscle significantly enhanced in the LPS treatment (P<0.05), meanwhile, the total antioxidant capacity (T AOC) levels significantly suppressed (P<0.01). The present results suggest that preslaughter LPS induced immunological stress could cause body oxidative damage and decrease oxidation resistance of boilers, resulting in poor growth performance and meat quality, moreover, these negative effects depend on stress intensity.