Context Evaluating performance of broilers fed diet included feed additives in stress conditions. Aims This study was conducted to investigate the effects of adding lysophospholipids (LPLs) and vitamin C (VC) to diet on growth performance, blood metabolites, antioxidant capacity and carcass traits in broiler chickens reared under low ambient temperature Methods A total of 288 male chicks (Ross 308) were allotted to four treatments with six replicates (n = 12) when they were 1-day-old. Based on a 2 × 2 factorial arrangement, four diets including dietary LPLs (0 or 1000 mg/kg) and VC (0 or 500 mg/kg) were formulated. According to the catalogue of LPL product, 100 000 kcal/Kg metabolisable energy was considered for LPLs. The house temperature was 32°C during the first week and 30°C for a second week. To induce cold stress, house temperature was decreased to 14°C by the step-down temperature program during the third week and maintained between 12 and 14°C for the rest of the study. Key results Increased feed intake and feed conversion ratio (FCR) were observed in chickens fed the LPL-supplemented diet during the first 2 weeks, but there was no significant difference in growth performance between the birds fed LPL-supplemented diet with control during cold stress condition. Decreased feed intake and bodyweight gain were observed in chickens fed VC-supplemented diet compared with control in cold stress condition. Dietary VC decreased blood concentration of triglyceride (TG) and very-low-density lipoprotein (VLDL). Decreased activity of superoxide dismutase (SOD) in breast muscle was observed in chickens fed VC-supplemented diet. A significant interaction between dietary LPLs and VC on relative weight and length of jejunum and ileum were detected. Comparable effects of LPLs and VC on inhibiting lipid peroxidation were observed. The free radical scavenging assay showed higher antioxidant activity of VC compared with LPLs. Conclusions Overall, dietary LPL supplementation did not improve broiler performance in cold stress condition, while the utilisation of 500 mg/kg VC in the ration reduced performance of broilers in low ambient temperature. Implications In low ambient temperature, adding 500 mg/kg VC to diet of broilers can be an effective to reduce blood concentration of TG and VLDL, with no adverse effect on FCR.

中文翻译：

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日粮添加溶血磷脂和维生素 C 影响低温环境下饲养肉鸡的生长性能、血清代谢物、抗氧化能力和胴体特性

背景 评估肉鸡饲喂日粮的性能包括应激条件下的饲料添加剂。目的 本研究旨在研究在日粮中添加溶血磷脂 (LPLs) 和维生素 C (VC) 对低温环境下饲养的肉鸡生长性能、血液代谢物、抗氧化能力和胴体性状的影响 方法 共 288 只雄性雏鸡(Ross 308) 在 1 日龄时被分配到四个处理，六个重复（n = 12）。基于 2 × 2 因子安排，制定了四种饮食，包括饮食 LPL（0 或 1000 毫克/千克）和 VC（0 或 500 毫克/千克）。根据LPL产品目录，LPL考虑100 000 kcal/Kg代谢能。第一周的室内温度为 32°C，第二周为 30°C。诱发冷应激，在第三周，通过降温程序将室内温度降至 14°C，并在研究的其余时间保持在 12 至 14°C 之间。主要结果 在前 2 周，饲喂添加 LPL 的日粮的鸡的采食量和饲料转化率 (FCR) 增加，但在冷应激期间饲喂添加 LPL 的日粮的鸡的生长性能没有显着差异状况。与冷应激条件下的对照相比，在饲喂 VC 补充日粮的鸡中观察到饲料摄入量和体重增加减少。膳食 VC 降低了甘油三酯 (TG) 和极低密度脂蛋白 (VLDL) 的血液浓度。在饲喂 VC 补充日粮的鸡中观察到胸肌中超氧化物歧化酶 (SOD) 的活性降低。检测到膳食 LPL 和 VC 之间对空肠和回肠的相对重量和长度的显着相互作用。观察到 LPL 和 VC 在抑制脂质过氧化方面的作用相当。自由基清除试验表明，与 LPL 相比，VC 具有更高的抗氧化活性。结论 总体而言，日粮中添加 LPL 并不能改善冷应激条件下的肉鸡生产性能，而在日粮中使用 500 mg/kg VC 会降低肉鸡在低温环境下的生产性能。启示 在低环境温度下，肉鸡日粮中添加500 mg/kg VC可有效降低TG和VLDL的血浓度，且对FCR无不良影响。自由基清除试验表明，与 LPL 相比，VC 具有更高的抗氧化活性。结论 总体而言，日粮中添加 LPL 并不能改善冷应激条件下的肉鸡生产性能，而在日粮中使用 500 mg/kg VC 会降低肉鸡在低温环境下的生产性能。启示 在低环境温度下，肉鸡日粮中添加500 mg/kg VC可有效降低TG和VLDL的血浓度，且对FCR无不良影响。自由基清除试验表明，与 LPL 相比，VC 具有更高的抗氧化活性。结论 总体而言，日粮中添加 LPL 并不能改善冷应激条件下的肉鸡生产性能，而在日粮中使用 500 mg/kg VC 会降低肉鸡在低温环境下的生产性能。启示 在低环境温度下，肉鸡日粮中添加500 mg/kg VC可有效降低TG和VLDL的血浓度，且对FCR无不良影响。