The disadvantages associated with the use of synthetic additives in animal production could threaten human and animal health, and the safety of animal-derived foods. This study assessed the growth performance, blood chemistry, immune indices, selected caeca bacterial population, muscle antioxidant enzyme activities, and meat quality in broiler chickens fed diet supplemented with antibiotic (70% oxytetracycline +30% neomycin), tert-butylhydroxytoluene or onion leaf powder (OLP). One day old Ross 308 chicks (n = 240) were assigned randomly to either D-1, control diet (CD) without additives; D-2, CD + 0.3 g kg⁻¹ antibiotic +0.15 g kg⁻¹ tert-butylhydroxytoluene; D-3, CD + 2.5 g kg⁻¹ OLP; or D-4, CD + 5 g kg⁻¹ OLP for 42 days.

中文翻译：

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肉鸡日粮中的洋葱叶和合成添加剂：对脾细胞因子、血清免疫球蛋白、盲肠细菌群和肌肉抗氧化状态的影响

在动物生产中使用合成添加剂的缺点可能会威胁人类和动物的健康以及动物源性食品的安全。本研究评估了饲喂添加抗生素（70% 土霉素 +30% 新霉素）、叔丁基羟基甲苯或洋葱叶的日粮的肉鸡的生长性能、血液化学、免疫指标、选定的盲肠细菌种群、肌肉抗氧化酶活性和肉质粉末（OLP）。一天大的罗斯 308 只小鸡 (n = 240) 被随机分配到 D-1、不含添加剂的对照饮食 (CD) 中；D-2，CD + 0.3 g kg ^-1抗生素+0.15 g kg ^-1 叔丁基羟基甲苯；D-3，CD + 2.5 g kg ^-1 OLP；或 D-4, CD + 5 g kg ⁻¹ OLP 42 天。