The objective of this study was to evaluate the interaction of zinc source (ZnSO₄ vs. zinc amino acid complex) and vitamin E level (50 IU vs. 100 IU) on performance and intestinal health of broilers exposed to a temperature challenge in the finisher period. A total of 1224 day old male Ross 308 broilers were randomly distributed among 4 dietary treatments (9 replicates per treatment). Dietary treatments were organized in a 2 × 2 factorial arrangement: two sources of zinc, 60 mg/kg of Zn as ZnSO₄.7H₂O or 60 mg/kg of Zn as zinc amino acid complexes (ZnAA) combined with two levels of vitamin E (50 or 100 IU/kg). Zinc and vitamin E were added to a wheat/rye-based diet that was designed to create a mild nutritional challenge. From day 28 until day 36 (finisher period), all birds were subjected to chronic cyclic high temperatures (32°C ± 2°C and RH 55–65% for 6 h daily). The combination of ZnAA and 50 IU/kg of vitamin E improved weight gain in the starter (day 0–10), finisher (day 28–36) and overall period (day 0–36) and feed conversion ratio in the starter (day 0–10) and finisher phase (day 28–36). Providing Zn as ZnAA significantly improved villus length and villus/crypt ratio in the starter, grower and finisher period and decreased infiltration of T-lymphocytes and ovotransferrin leakage in the finisher period. In conclusion, providing broilers with a diet supplemented with ZnAA and a vitamin E level of 50 IU/kg, resulted in better growth performance as compared to all other dietary treatments. Interestingly, under the conditions of this study, positive effects of ZnAA on performance did not occur when vitamin E was supplemented at 100 IU/kg in feed. Moreover, providing zinc as zinc amino acid complex improved intestinal health.

中文翻译：

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维生素 E 水平和日粮锌源对育肥期暴露于温度挑战的雄性肉鸡性能和肠道健康参数的影响

本研究的目的是评估锌源（ZnSO ₄与锌氨基酸复合物）和维生素 E 水平（50 IU 与 100 IU）对暴露于育肥机温度挑战的肉鸡的性能和肠道健康的相互作用时期。总共 1224 日龄雄性 Ross 308 肉鸡随机分布在 4 个日粮处理中（每个处理 9 个重复）。饮食处理按 2 × 2 因子排列进行组织：两种锌源，60 mg/kg Zn，ZnSO ₄ .7H ₂O 或 60 mg/kg 锌作为锌氨基酸复合物 (ZnAA) 与两种水平的维生素 E（50 或 100 IU/kg）结合。锌和维生素 E 被添加到以小麦/黑麦为基础的饮食中，旨在创造温和的营养挑战。从第 28 天到第 36 天（育肥期），所有鸡只经受慢性循环高温（32°C ± 2°C 和 RH 55-65%，每天 6 小时）。ZnAA 和 50 IU/kg 维生素 E 的组合改善了开食鸡（第 0-10 天）、育肥鸡（第 28-36 天）和整个时期（第 0-36 天）的体重增加以及开食鸡（第0–10）和终结者阶段（第 28–36 天）。以 ZnAA 形式提供 Zn 显着改善了起子、生长和肥育期的绒毛长度和绒毛/隐窝比，并减少了肥育期 T 淋巴细胞的浸润和卵转铁蛋白渗漏。综上所述，与所有其他日粮处理相比，为肉鸡提供添加了 ZnAA 且维生素 E 水平为 50 IU/kg 的日粮导致了更好的生长性能。有趣的是，在本研究的条件下，当在饲料中添加 100 IU/kg 的维生素 E 时，ZnAA 对生产性能没有积极影响。此外，以锌氨基酸复合物形式提供锌可改善肠道健康。