Experimental pathological Studies On Infectious Coryza Vaccine In Chickens

The present investigations were performed on two hundred chickens,which classified into ten equal groups. The 1 S\ 2nd, 3rd, 4th and 5th groups were used as experimental control. other groups were vaccinated with imported bacterin (gps 7 and 8) and autogenous bacterin (gps 9 and 10 ) then challenged with virulent HPG stlining with metaplasia into goblet cells and lymphocytic infiltrations were seen. The chickens which had been vaccinated with imported vaccine thenchallenged with HPG (gps 7 and 8) showed nasal discharge and swollen faceand unilateral mild swelling of infraorbital sinuses, in addition to mortality rate (5%) after their challenge in chickens received single dose, while double doses of vaccine gave good protection (100%).The chickens vaccinated with commercial autogenous bacterin (gps 4and 5)revealed neither clinical signs nor post mortem lesions.The chickens vaccinated with commercial autogenous bacterin and had been challenged with virulent HPG strain (gps 9, 10) showed no clinical signs, no mortality after their challenging and 1000/0 protfindings reflected normal body reaction, including lymphocytic aggregations and proliferative glands in the mucosa and submucosa of nasal sinuses, larynx and trachea, beside severely enlarged lymphoid follicles were also detected. Lungs showed hyperplastilymphocytosis and heterophilia in some portal blood vessels, the latter wasrepresented by numerous lymphocytes or heterophils in the lumina of theaffected blood vessels