The Studies On The Toxicology Of Sub-Chronic Cadmium Poisoning To The Ovary Of Chicken

Model hens of cadmium poisoning were duplicated by adding different levels of cadmium in the ration to study the toxicity effect and mechanism of cadmium on reproduction in chicken.Clinical symptom,anatomy and ultrastructure of ovarian were observed; oxidative stress, apoptosis and the level of FSHR and LHRmRNA expression in the ovarian were measured by semi-quantitativeRT-PCR,enzymohistochemistry,pathobiologic observation,TUNEL. The results showed as follows:1.Cadmium induced the damage of ovary and reduced fertilities of chicken. the abundant pathology histology basis were offered to judge the toxicity effect of cadmium by the difference of pathology between cadmium group and control group.2.Cadmium induced the oxidative stress of ovarian, decreased the activity of GSH-Px and SOD, increased the activity of NOS and the content of NO and MDA and destroyed antioxidative defense system of organism, removed the free radical and induced ovary oxidative damage.3.Cadmium influenced enzyme activity of the hen's ovary , decreased the activity of SDH, ALP, G-6-Pase, Ca²⁺-ATPase, Mg²⁺-ATPase, increased the activity of ACP, interfered tissue metabolism and depressed the developing of ovarian follicle.4.Cadmium caused hen's ovary cell and ovarian follicle granular cell apoptosis.5.Cadmium lowered the content of E₂,P₄,FT₃,FT₄, disordered the endocrine and affected the developing of ovarian follicle.6.Cadmium reduced FSHR, LHRmRNA expression, depressed the developing of ovarian follicle. It verified further that the cadmium interfered the transcription of gene which promotes ovarian follicle cell's developing. It might be one mechanism of the cadmium'reproduction toxicity.The study indicated that the cadmium caused reproduction organ pathological damage , suppressed the reproductive function, induced oxidative stress, destroyed enzyme activity, interfered FSHR, LHRmRNA expression, and promoted ovarian follicle granular cell apoptosis.The reproductive toxicology of cadmium on hens was studied in the level of organ, cell, sub-cellule and molecular, and the reproductive toxicity mechanism of cadmium on hens was discussed.So that we can realize the toxicity of the cadmium further and also have established the theoretical foundation for removing the cadmium caused chicken's toxic research. It will provide theoretical basis for research on environmental toxicology and preventing and curing the cadmium poisoning. Also, it will raise human environmental protection consciousness, promote the healthy...