1Mineral Nutrition Research Division,Institute of Animal Science,Chinese Academy of Agricultural Sciences (CAAS),Beijing 100193,P. R. China.
2Department of Animal Science,Hebei Normal University of Science and Technology,Qinhuangdao 066004,P. R. China.
Animal. 2019 May;13(5):983-991. doi: 10.1017/S1751731118002379. Epub 2018 Oct 2.
Dietary supplementation with the organic chromium (Cr) has been shown to positively affect the immune function of poultry. However, to our knowledge, no experiment has been done to directly compare the impacts of Cr chloride and chromium picolinate (CrPic) on the immune responses of broilers vaccinated with Avian Influenza (AI) virus vaccine. Therefore, the present experiment was conducted to investigate the effects of supplemental Cr sources (Cr chloride and CrPic) and levels on the growth performance and immune responses of broilers vaccinated with AI virus vaccine so as to provide an effective nutritional strategy for improving immune function of broilers. A total of 432 1-day (d)-old male broiler chicks were used in a 1 plus 2×4 design. Chickens were given either a diet without Cr supplementation (control) or diets supplemented with 0.4, 0.8, 1.6, or 3.2 mg Cr/kg as either Cr chloride or CrPic for 42 d. Compared to the control, dietary Cr supplementation had no effect (P>0.05) on average daily gain, average daily feed intake and gain : feed of broilers during the starter and grower phases, but increased (P<0.05) the relative weights of bursa of fabricius on d 21 and thymus, spleen, or bursa of fabricius on d 42, serum antibody titers against AI virus on d 21, 28, 35 and 42, blood T-lymphocyte transformation rate on d 28 and 42, blood T-lymphocyte percentage on d 42, and serum interleukin-2 contents on d 28. Broilers fed the diets supplemented with the inorganic Cr chloride had higher (P<0.05) weights of thymus, spleen and bursa of fabricius than those fed the diets supplemented with the CrPic on d 42. In addition, broilers fed the diets supplemented with the CrPic had higher (P<0.05) antibody titers against AI virus than those fed the diets supplemented with the inorganic Cr chloride on d 21 and 35. These results indicate that dietary Cr supplementation improved immune responses of broilers vaccinated with AI virus, and the inorganic Cr chloride was more effective than the CrPic in increasing the relative weights of lymphoid organs, however, the CrPic was more effective than the inorganic Cr chloride in enhancing the serum antibody titer against AI virus.
日粮中添加有机铬（Cr）已被证明可对家禽的免疫功能产生积极影响。然而，据我们所知，尚无实验直接比较 Cr 氯化物和吡啶甲酸铬（CrPic）对接种禽流感（AI）病毒疫苗的肉鸡免疫反应的影响。因此，本实验旨在研究补充 Cr 源（Cr 氯化物和 CrPic）和水平对接种 AI 病毒疫苗的肉鸡生长性能和免疫反应的影响，为提高肉鸡免疫功能提供有效的营养策略。选用 432 只 1 日龄（d）雄性肉鸡雏鸡进行 1 加 2×4 设计。鸡只给予不含 Cr 补充剂的饮食（对照）或补充 0.4、0.8、1.6 或 3.2mg/kg Cr 作为 Cr 氯化物或 CrPic 的饮食，为期 42d。与对照组相比，日粮 Cr 补充对肉鸡在育雏期和生长期的平均日增重、平均日采食量和增重：采食量无影响（P>0.05），但增加了（P<0.05）21 日龄法氏囊、42 日龄胸腺、脾脏或法氏囊的相对重量，21、28、35 和 42 日龄血清对 AI 病毒的抗体滴度，28 和 42 日龄血液 T 淋巴细胞转化率，42 日龄血液 T 淋巴细胞百分比和 28 日龄血清白细胞介素-2 含量。饲喂补充无机 Cr 氯化物日粮的肉鸡 42 日龄的胸腺、脾脏和法氏囊重量高于饲喂补充 CrPic 日粮的肉鸡（P<0.05）。此外，饲喂补充 CrPic 日粮的肉鸡 21 日和 35 日血清抗 AI 病毒抗体滴度高于饲喂补充无机 Cr 氯化物日粮的肉鸡（P<0.05）。这些结果表明，日粮 Cr 补充剂可改善接种 AI 病毒疫苗的肉鸡的免疫反应，无机 Cr 氯化物在增加淋巴器官的相对重量方面比 CrPic 更有效，但 CrPic 在提高血清抗 AI 病毒抗体滴度方面比无机 Cr 氯化物更有效。
