some Studies onViral Respiratory Afections In Chickens In The Area og Upper Egypt

A serological survey was conducted for screening ch+cken flocks in the area of As-siut and El-Wadi - El gadid provi!lces to infectious bronchitis virus.The Agar gel precipitin test and serum meutralization test were used in this study, 68 out of 1138 serum samples(6 %) showed precipitating antibodies for IB viral agent.The percentage of positive birds ranged between (1~72 - 28.5) qmong the examined flocks.In a study on the status of ND in Upper Egypt, 14 ~solates were obtained out of 32 cases of respiratorytroubles. Seven isolates of them WeJ”3 inden tified by :ELD50, M:D:T., HA - activity of different mammalian andavi3n erythrocytes, thermostabilty of Haemagglutinins at56 oc, I~C:P and I)(P indexs for 4 - 6, weeks age squabs.According to these criteria, six strains could be classifiedunder the Velogenic V~pic strains of Newcnstle disease ~irus and one strain under - the MefUgenic ones.More detailed studies should be conducted on the status of ND in this area suitable. and schemes of vaccinations most suitable.