coryvac A Hen is Only An Egg’s Way of Making Another Egg. Composition; Inactivated trivalent vaccine against Infectious Coryza vaccine Avibacterium parigallinarum Serotypes (A, B, C)Coryvac provide broad protection against 3 serotypes of Infectious Coryza. It ensures strong and long-lasting immune response.Dosage; 0.5ml of vaccine I.M (chest/thigh muscles) or S.C into the lower third part of the neck. coryvac