Effects of in ovo injection of nano-selenium and nano-zinc oxide and high eggshell temperature during late incubation on antioxidant activity, thyroid and glucocorticoid hormones and some blood metabolites in broiler hatchlings

ABSTRACT. This experiment was conducted to evaluate the effects of in ovo injection of nano-selenium (Nano-Se) and nano-zinc oxide (Nano-ZnO) and high eggshell temperature (EST) during late incubation on blood parameters of broiler hatchlings. A total of 750 fertile eggs, were weighed and randomly distributed among 5 treatment groups on each of 5 replicate tray levels. The injection was performed on 17 d of incubation. Treatments included of: 1) Eggs not injected and incubated at normal EST (control); 2) Eggs not injected and incubated at high EST; 3) Eggs injected NaCl solution and incubated at high EST (sham); 4) Eggs injected NaCl solution containing 40 µg Nano-Se and incubated at high EST; 5) Eggs injected NaCl solution containing 500 µg Nano-ZnO and incubated at high EST. EST of 37.8ºC (normal) or 38.9ºC (high) was applied from d 19 to 21 of incubation. In ovo injection of Nano-Se and Nano-ZnO significantly increased activity of GSH-Px and SOD and total protein, but decreased the levels of corticosterone, cortisol, T4 and T3 at high EST. Injection of Nano-Se and Nano-ZnO had a significant role in alleviating the negative effects of high temperature incubation and heat stress by increased antioxidant activity and reduced oxidative stress.

摘要。本实验旨在评估孵化后期卵内注射纳米硒（Nano-Se）、纳米氧化锌（Nano-ZnO）与高蛋壳温度（EST）对肉鸡雏鸡血液指标的影响。共计750枚受精蛋经称重后，随机分配至5个处理组，每组设置5个重复托盘水平。注射操作于孵化第17天进行。处理组具体如下：1）未注射且于正常蛋壳温度下孵化的鸡蛋（对照组）；2）未注射且于高蛋壳温度下孵化的鸡蛋；3）注射氯化钠溶液且于高蛋壳温度下孵化的鸡蛋（假处理组）；4）注射含40 μg纳米硒的氯化钠溶液且于高蛋壳温度下孵化的鸡蛋；5）注射含500 μg纳米氧化锌的氯化钠溶液且于高蛋壳温度下孵化的鸡蛋。自孵化第19天至第21天，分别采用37.8℃（正常）或38.9℃（高）的蛋壳温度进行处理。在高蛋壳温度条件下，卵内注射纳米硒与纳米氧化锌可显著提升谷胱甘肽过氧化物酶（GSH-Px）、超氧化物歧化酶（SOD）活性及总蛋白含量，同时降低皮质酮、皮质醇、甲状腺素T4与三碘甲状腺原氨酸T3的水平。纳米硒与纳米氧化锌的卵内注射可通过提升抗氧化活性、降低氧化应激，有效缓解高温孵化与热应激带来的负面影响。