Departments of Physiology Faculty of Veterinary Medicine, University of Erciyes, Kayseri, Turkey.
Animal Nutrition and Nutritional Diseases, Faculty of Veterinary Medicine, University of Erciyes, Kayseri, Turkey.
J Anim Physiol Anim Nutr (Berl). 2020 Jan;104(1):136-143. doi: 10.1111/jpn.13210. Epub 2019 Sep 23.
This study aimed to investigate the effect of l-carnitine and energy level and on oxidant/antioxidant balance in laying hens subjected to high stocking density. A total of 176, 32-week-old laying hens were assigned to eight groups with four replicates and hens in four groups were placed at the normal stocking densities of 500 cm /hen (four hens per cage) and in the remaining four groups were placed at the high stocking densities of 287.5 cm /hen (seven hens per cage). Hens received diets of high (2,850 kcal/kg ME) or normal (2,650 kcal/kg ME) energy which are supplemented with 0 or 200 mg/kg l-carnitine for 70 days. Results showed that exposure to high stocking density increased (p < .05) plasma malondialdehyde (MDA) and nitric oxide (NO) levels and decreased (p < .05) erythrocyte superoxide dismutase (SOD), catalase (CAT) and superoxide dismutase (GPx) activities. l-carnitine supplementation increased (p < .05) erythrocyte SOD, CAT and GPx activities, and decreased (p <.05) MDA and NO level in high stocking densities. The oxidan/antioxidan balance of birds was not influenced by increasing dietary energy level. The results of the present study indicate that the supplementation of l-carnitine to the birds subjected to high stocking density could effectively reverse the negative effects of high stocking density by improving oxidant/antioxidant balance. Therefore, l-carnitine supplementation at level of 200 mg/kg to diet may be as a favourable alternative to deal with oxidative stress caused by high stocking density in laying hens.
本研究旨在探讨高饲养密度对产蛋鸡能量水平和氧化应激/抗氧化平衡的影响。共选择 176 只 32 周龄的产蛋鸡，分为 8 组，每组 4 个重复，其中 4 只鸡/笼的正常饲养密度组有 4 组，7 只鸡/笼的高密度饲养密度组有 4 组。鸡接受高能（2850kcal/kg ME）或正常能（2650kcal/kg ME）日粮，日粮中添加或不添加 0 或 200mg/kg 的左旋肉碱，共 70 天。结果表明，高密度饲养增加了（p<.05）血浆丙二醛（MDA）和一氧化氮（NO）水平，降低了（p<.05）红细胞超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和谷胱甘肽过氧化物酶（GPx）活性。左旋肉碱的添加增加了（p<.05）高密度饲养的红细胞 SOD、CAT 和 GPx 活性，降低了（p<.05）MDA 和 NO 水平。增加日粮能量水平并没有影响鸟类的氧化还原平衡。本研究结果表明，在高密度饲养的鸡日粮中添加左旋肉碱可以通过改善氧化应激/抗氧化平衡来有效逆转高密度饲养的负面影响。因此，在产蛋鸡日粮中添加 200mg/kg 的左旋肉碱可能是一种应对高密度饲养引起的氧化应激的有利选择。
