Studies On The Molecular Mechanism Of Selenium-Penia In Chicken

Studies on selenium are the hotspot and focus of microelement study at present. This is because selenium-penia is a global disease, which infringes upon all kinds of animals and human beings and causes serious damages. At present, we have made great achievements in preventing and curing of selenium-penia, but selenium-penia still frequently happens in all kinds of animals. In addition, selenium has important biological characters, great developmental potentials and applied value. Studies on selenium have become an important offshoot content in animal nutrition research and a more active research field in 21 century, which likewise have enhanced the combination of related subjects between animal nutrition and animal medicine. Therefore, investiagating molecular mechanisms of selenium-penia in diverse animals have important theoretical value and academic meaning.In order to deeply investigate the molecular mechanism of selenium-penia in chicken , this experiment adopted a contrast means in different groups and established experimental model of chicken with selenium-penia. By observing clinical symptoms, killing periodically and anatomizing chicken, we determined selenium content and routine test of GSH-px and ID-â… (two selenoproteins ). The main aspects of this research were follows: The effect of selenium deficiency on the metabolism of free radicals and the function of anti-oxidative system in chicken in detail were studied; The damadging mechanism of liver, muscle, pancreas, thyroid in chicken with selenium-penia in detail was also investigated; the change of cytokines level in chicken with selenium-penia was firstly examined in order to discuss the decline of immune mechanism caused by selenium deficiency; apoptosis of histocyte of thyroid, liver, chest muscle, pancreas and thymus etc in chicken with selenium-penia was firstly observed in order to reveal two kinds of death mechanisms(necrosis and apoptosis) of cells in chicken with selenium-penia; the immune system of erythrocyte and bilirubin metabolism in chicken with selenium-penia was analyzed; the effect of selenium deficiency on erythrocyte in chicken in detail was studied in order to ascertain the mechanism of anemia in chicken with selenium-penia. The main conclutions are as follows: This research successfully copied the model of chicken with selenium-penia and acquired consistent results with the natural case in clinical symptoms, pathological dissection and pathological histology and observed ultrastruction of liver, pancreas, thymus and muscle in pathological histology, which added to new contents for the reserch of selenium-penia, at the same time provided credible experimental evidences for the clinical diagnosis of chicken with selenium-penia by collecting clinical symptoms and results of pathology and laboratory, filtrating and appraising indexes of diagnosis of chicken with selenium-penia, increasing new indexes of diagnosis that include ID etc. Selenium deficiency in chicken causes the decrease of T-AOC and GSP-px activity,the increase of MDA content. These make anti-oxidative capacitity decrease in orgnism, which not only can't destroy the peroxide and prevent the cellular and subcellular membrane from damage of the preoxide, but also promote the production of excess OFR and NO in vivo. Finally these changes make cell stay in oxidative stress condition and damage the cellular membrane system and cause metabolic disorder of matter and energy, which induces a range of lesion including anemia, lag growth, exudative diathesis, motor disturbance, haemorrhage and necrosis of tissues, nutrition deficiency. All above form pathological foundation of selenium-penia.This research first confirms that deficiency of selenium in chicken induces changes of IL-1, IL-2, EPO and TNF content including the decrease of IL-1 and IL-2 content in the serum which brings to some effects on multiplication and differentiation of lymphocyte and extensive effects on immune depression in organism. The decrease of EPO content and the increase of TNF content in th...