铅、镉联合暴露对公鸡生长早期生殖发育的影响

Effects of Concurrent Exposure to Plumbum and Cadmium on Reproductive Development in Cocks

为研究铅、镉联合暴露对公鸡生长早期的生殖毒性,150只1日龄雄性AA(爱拨益加)肉鸡被随机分成5组:C、T1、T2、T3和T4,每组6个重复,每重复5只,分别饲喂基础日粮及基础上添加10mg·kg-1铅+2mg·kg-1镉、10mg·kg-1铅+50mg.kg-1镉、100mg·kg-1铅+2mg·kg-1镉、100mg·kg-1铅+50mg·kg-1镉的实验日粮。分别在饲喂2周、4周和6周时于每重复中随机选取1只中等大小的鸡即每组分别取6只鸡称重、宰杀,对脏器重和血清激素水平等指标进行检测,并作睾丸的组织形态学观察。结果表明:与C比较,2周时,T2体重显著降低(p<0.05);4周和6周时,T2和T4体重及肝脏重显著降低(p<0.05);但6周时,T1肝脏重显著升高(p<0.05);各暴露组比较,高镉组较低镉组指标降低明显,部分组间有显著差异(p<0.05),这说明镉在铅镉联合毒性损伤过程中发挥主导作用。另外,6周时,T2和T4睾丸出现不同程度病理变化,这说明铅镉联合暴露对生精小管产生毒性作用。

To investigate the toxicity of concurrent exposure to plumbum and cadmium in the reproductive system of cocks,one hundred and fifty 1-day cocks were separated into the following groups：C：control group,T1：lead acetate（10mg·kg-1）＋cadmium chloride（2 mg·kg-1）group,T2：lead acetate（10 mg·kg-1）＋cadmium chloride（50 mg·kg-1）group,T3：lead acetate（100 mg·kg-1）＋cadmium chloride（2 mg·kg-1）group,T4：lead acetate（100 mg·kg-1）＋cadmium chloride（50 mg kg-1）group.The weight of body,liver,testes and the concentration of testosterone in serum were detected at the second,fourth and sixth week,respectively.At the end of the experiment,the morphology of the testes were examined.The growth of the cocks in treated groups was retarded.In comparision with C,significant decrease was observed in the body weight of T2（p0.05）at the second week,in addition,the body and liver weight of T2 and T4 also decreased at the fourth and sixth week.However,significant increase occurred in the liver weight of T1 at the sixth week.In comparision among treated groups,there was more significant decrease in some indicators of high cadmium groups than that of low cadmium groups（p0.05）.Furthermore,histopathological lesions were presented in the testes of T2 and T4 at sixth week.This experience indicated that combination of plumbum and cadmium has toxic effects on seminiferous tubules.Cadmium plays a leading role in this effect.