日粮锌硒水平对肉鸡小肠黏膜结构的影响

为了探讨微量元素锌和硒互作对肉鸡小肠黏膜结构的影响 ,将 2 4只 1日龄AA肉鸡随机分为 3组 ,分别饲喂添加有高锌高硒 (锌 1 0 0 0mg/kg ,硒 5mg/kg)、低锌低硒 (锌 34mg/kg ,硒 0 .0 8mg/kg)和常锌常硒 (锌 5 0mg/kg ,硒 0 .1 5mg/kg)的日粮 4 5d后 ,观察小肠黏膜的形态结构变化。结果表明 ,高锌高硒或低锌低硒组肉鸡的小肠黏膜结构有明显的损伤 ,表现为黏膜厚度和绒毛高度下降 ,绒毛高度 /腺窝深度的比值减少 ,肠黏膜上皮细胞萎缩。尤其是高锌高硒对空肠的损伤最为严重。而常锌常硒组肉鸡小肠黏膜的形态结构正常。研究结果表明 ,日粮中按锌 5 0mg/kg和硒 0 .1 5mg/kg的比例添加 ,对于维持小肠黏膜的正常形态结构是合适的 ;过高或过低的锌和硒对小肠黏膜有毒性作用 ,且高锌和高硒可相互促进其毒性作用

Effect of different levels of zinc and selenium in diet on the structure of mucosa epithelium in broiler small intestine

To explore effect of trace elements zinc, selenium and their interaction on the structure of mucosa epithelium in the broiler small intestine, 24 one day old AA broilers were divided into three groups, and were fed with the different diets including high zinc selenium (Zn 1 000 mg/kg, Se 5 mg/kg) , low zinc selenium (Zn 34 mg/kg, Se 0.08 mg/kg), and normal zinc selenium (Zn 50 mg/kg, Se 0.15 mg/kg) , respectively. After forty five days, the broilers were killed and the structure of mucosa epithelium in the small intestine was observed. The results showed that in two groups of high zinc selenium and low zinc selenium, the structures of mucosa epithelium in the duodenum and the jejunum were injured. The thickness of mucosa epithelium, height of villus and V/C value (height of villus/depth of crypt) decreased. Their epithelium of mucosa was atrophy and defluxion, especially in the high zinc selenium group. But the structures of mucosa epithelium were normal in the normal zinc selenium group. This study indicated that the supplementary level of selenium at 0.15 mg/kg and zinc at 50 mg/kg in diet should be an appropriate ratio which would keep the normal structure of mucosa epithelium in the broiler small intestine.