铁和维生素A及其互作效应对产蛋鸡胫骨质量的影响

Effects of Iron, Vitamin A and Their Interaction on Tibial Quality of Laying Hens

试验旨在探讨铁和维生素A及其互作效应对产蛋鸡胫骨质量（胫骨长度、胫骨中截面直径、胫骨重量、胫骨强度、胫骨钙磷含量）的影响。采用3×2（铁×维生素A）完全随机试验设计。饲粮铁的添加水平为0、30、60 mg/kg,维生素A的添加水平为4 000、8 000 IU/kg。试验期为8周,分前期（27-30周龄）和后期（31-34周龄）2个阶段。选用27周龄商品代海兰褐蛋鸡432只,随机分为6组,每组6个重复,每重复12只鸡。结果表明：饲粮铁的添加量为0 mg/kg时,蛋鸡胫骨长度、胫骨中截面直径和胫骨强度均达到最高;随着饲粮维生素A添加水平的增高,产蛋鸡胫骨长度、胫骨中截面直径、胫骨重量和胫骨钙含量均增加;铁和维生素A互作效应对蛋鸡胫骨质量的影响表现为铁（60 mg/kg）×维生素A（4 000 mg/kg）组较好。饲粮添加低剂量铁（0-30 mg/kg）和高剂量维生素A（8 000 IU/kg）可获得较理想的胫骨质量。铁和维生素A之间存在互作效应。

To explore the effect of iron, vitamin A and their interaction on tibial quality （tibial length, diameter, weight, strength, calcium and phosphorus content） of laying hens, the trial employed a complete random design of 3×2 （Fe×VA）. Diet was supplemented with iron at 0, 30, 60 mg/kg, with vitamin A at 4 000, 8 000 IU/kg. Hyline brown layers of commercial generation at 27 weeks of age were assigned at random to 6 groups, with 6 replicates in each group and 12 hens replicate. The trial was divided into two stages, with first stage being week 27-30 and second stage being week 31 -34. When iron was supplemented at 0 mg/kg, the hens reached the highest values of tibial length, diameter and strength. The tibial length, diameter, weight, strength and calcium content were increased with the increasing of vitamin A levels. Study of the interaction between iron and vitamin A indicated that treatment with 60 mg/kg iron ×4 000 IU/kg vitamin A had the best performance. Ideal tibial quality can be achieved by dietary supplementation with low dose of iron （0 - 30 mg/kg） and high dose （8 000 IU/kg） of vitamin A. There was interaction between iron and vitamin A.