EXPRESSION OF IMMUNITY GENES IN RED BONE MARROW OF CROSS-LOMAN BROWN CHICKS UNDER INFLUENCE OF VACCINATION AND INFECTIOUS ANEMIA VIRUS IN CHICKEN
Infectious anemia of chickens is a dangerous immunosuppressive viral disease of poultry. Traditionally, both egg and broiler domestic poultry farms suffer from the disease. This disease, caused by a DNA-containing virus of the Circoviridae family, affects the main immunocompetent organs of chickens (red bone marrow, thymus, bursa of Fabricius, spleen), causing a severe immunosuppressive state in the bird, leading to death from secondary pathogenic micro ora. Also, this virus causes a signi cant change in the expression of the main immunity genes (IL8L2, PTGS2, IRF7 and AvBD-11) when a bird is infected. An experiment was conducted on chickens of the Lohman Brown cross 95-day-old to infect chickens with the eld infectious anemia virus and vaccinate with the Nobilis® CAV P4 vaccine manufactured by MSD Animal Health on the basis of the Scienti c and Consultative Diagnostic Center for Poultry Farming of the St. Petersburg State University of Veterinary Medicine. Based on the obtained results, authors concluded that the pathogenic infectious anemia virus is able to suppress the expression of in ammatory cytokines and cyclooxygenase-2 in the red bone marrow cells of infected chickens compared to the vaccine virus due to a more active effect on the red bone marrow cells, while the Nobilis vaccine ® CAV P4 has a prolonged action in the body of birds. Also, red bone marrow cells respond to viral interference with the expression of the IRF7 and AvBD-11 genes and the synthesis of antiviral defense factors differently, depending on the nature of the in ltrated virus. Data have been obtained that the vaccine virus is able not to activate the expression of the IRF7 gene in red bone marrow cells in vaccinated birds.