锌源和锌水平对断奶应激仔猪血清激素水平的影响

【目的】本试验旨在研究不同锌源和不同锌水平的高锌日粮对断奶应激仔猪血清激素水平的影响。【方法】选用100头26±2日龄"杜长大"三元杂交断奶仔猪,按体重和性别随机分成5组,每组20头,分别饲喂基础日粮、基础日粮+2 000 mg·kg-1氧化锌、基础日粮+3 000 mg·kg-1氧化锌和基础日粮+250 mg·kg-1 蛋氨酸锌、基础日粮+500 mg·kg-1 蛋氨酸锌。试验期14 d。断奶后于前腔静脉采血,测定部分血清激素水平。【结果】高锌日粮能显著提高断奶应激仔猪体重、平均日增重和日采食量,降低料重比和断奶后腹泻率;断奶应激仔猪血清生长激素（GH）、胰岛素（INS）、胰岛素样生长因子-Ⅰ(IGF-I)和三碘甲腺原氨酸（T3）水平显著下降,血清皮质醇水平显著升高。日粮添加高锌显著提高断奶仔猪血清GH、INS、IGF-I和T3水平。【结论】高锌日粮能抑制仔猪断奶应激,调节仔猪促生长激素轴。

Effect of Zinc Resources and Levels on Serum Hormone Levels of Weanling Stress Piglets

【Objective】The purpose of this experiment was to study the effects of different dozes and kinds of high zinc diets on serum hormone levels of weanling stress piglets.【Method】One hundred "Duroc ×Landrace×Yorkshire" crossbred weanling piglets [(26 ±2) d of age] were randomly divided into 5 groups of 20 piglets each by weight and sex, fed with basal diet, basal diet plus 2 000 or 3 000 mg·kg-1 zinc (from ZnO), and basal diet plus 250 or 500 mg·kg-1 zinc (from Zn-Met), respectively. The trial was conducted for 14 d. Blood samples were taken from the anterior vena cava for measuring some serum hormone levels.【Result】High zinc diets increased significantly absolute weight, average daily gain, and average daily feed intake of weanling stress piglets, decreased the ratio of feed to gain and postweaning diarrhea rates. Serum GH, INS, IGF-I, T3 levels of weanling stress piglets decreased, and serum cortisol levels increased significantly. High zinc diets increased significantly serum GH, INS, IGF-I, and T3 levels. 【Conclusion】The results showed that high zinc diet can inhibit weanling stress and modulate growth-promoting hormone axis of piglets.