Abstract

Histological study was performed to know the vaccinal reactions for infectious bronchitis on broiler type Ross (308) by using (H120) vaccinal strain, at one day old by three routs. Eye drop, Drinking water and spraying, respectively by two experiment. First experiment the serum was taken for serological test (ELIZA) and samples from (treachea, lung and kidney), were taken for histopathological examination at days 3, 6, 9, 12 after first vaccination. In the second experiment samples from (treachea, lung and kidney) were taken at days 18, 21, 24, 27, 30 and 35 after second vaccination. The result of first experiment showed that vaccination by eye drops gives best result than both spraying and drinking water from serological level, and no histological changes were observe due to no vaccinal reaction in the first days after vaccination. In the other hand the result of second experiment showed more histological reaction for both drinking water and spraying routs.