成都白鸡育雏日粮锌的适宜添加量及缺锌对含硫氨基酸利用的影响

研究了植物性饲料组成的低锌日粮的不同加锌水平对成都白鸡育雏期(0～6周龄)的生长、血清锌和血清碱性磷酸酶活性的影响,结果表明:生长、血清锌和血清碱性磷酸酶活性都可作鸡体锌状况的标识。根据这三个指标,成都白鸡育雏日粮锌的适宜添加量为42ppm(总锌约70ppm)。又用两种类型日粮(实用日粮和半合成日粮)初步探讨了锌和含硫氨基酸的互作。结果表明:缺锌和临界缺锌鸡对含硫氨基酸的利用能力下降;含硫氨基酸对锌吸收有促进作用。

THE APPROPRIATE DIETARY ZINC SUPPLEMENTATION FOR WHITE CHENGDU CHICKS AND THE EFFECT OF ZINC DEFICIENCY ON SULFUR AMINO ACID UTILIZATION

The study was done to find out the proper amount of dietary zinc supplem-entation for white Chengdu chicks to diets consisting of common plant feeds.Weight gain, serum zinc and serum alkaline phosphatase activity were determined.The results show that these three indexes are good criteria for assessing the zincrequirement of chicks and that 42 ppm of dietary zinc supplementation (70ppmdietary zinc concentration) is appropriate for white Chengdu chicks (0--6weeksold). To observe the interaction between zinc and sulfur amino acid, practicaldiet and semi-synthetic diet were used. Serum SO_4~(2-) and fecal-urinary SO_4~(2-)and total sulfur were determined. These results show a poor utilization of sulfuramino acid in deficient and border zinc deficient chicks and an increased absorptionof zinc with the increse of sulfur amino acid in diet