Broiler Pulmonary Tissue Endothelin-1and Its Receptor Expression Effect On The Hypoxia

Pulmonary Hypertension Syndrome (PHS) is a common disease in broiler’s fast growth period. The main symptoms of PHS contain functional failure in heart and lungs, hydrops in enterocoelia, because of which it’s also called ascites syndrome (AS). Endothelin-1(ET-1), which exists in and excretes from endotheliocyte, is a vasoactive peptide and plays important regulate roles in cardiovascular system. Through the use of oxygen-deficient environment, animal experiment and Molecular biology methods, this research aims to invest the present PHS reality in broiler, study the expression of the ET-1receptor gene in the cardiovascular remolding period caused by the pulmonary hypertension in the oxygen-deficient environment. Meanwhile, the pathogenesis of PHS from the view of ET-1and it’s receptor are analysized. The main results of this research are as follows:(1) The morbidity of broilers Fed with high energy forage in low oxygen status was6.7%at the14th day, while the control group had no symptoms. At the21st and28th day, the morbidity of test group was33.3%and90%respectively, while the control group was6.7%and50%(P<0.05). Compared with control group, the growing performance of test group in14,21and28day decreased19.5%(P<0.5)、10%(P<0.5)、29%(P<0.5) respectively,.(2) Expression of different age and different levels of hydrop in enterocoelia were studied through the method of Real-Time PCR. In the test group, the expression of ET-1mRNA in lung significantly increased then the control group. With the hydrops level getting deep, the expression of ET-1also added up, and the express level in test group was higher than control group. The expression of ETA-R and ETB-R in lungs in test group was also higher than control group.The result of this research manifested that the oxygen-deficient is an important factor of ascites syndrome (AS). Low oxygen condition can reduce the growth of dorkings and the feed efficient. This suggests ET-1and its receptors take part in important activities in the mechanism of the rise in pulmonary hypertension and ascites syndrome.