The Histological Changes in Lungs on Chickens Vaccinated against Avian Infectious Bronchitis with Strains Ma5+Clon30 and H-120

This paper presents a review of the histological modifications in lung on vaccinatedchickens with “H-120” and “Ma5+Clon30” strains, administered by spray method. Were establishedthat “H-120” vaccine strains against avian infectious bronchitis make the minor changes in lung tissue,which is observed at 10, 20 and 30 days after vaccination and expressed with lymphoblast and plasmacells, in some regions capillary congestion is observed and return to normal structure after 40 daysafter vaccination. After the vaccination with “Ma5+Clon30” vaccine strain in bronchial sub mucosawas isolated a diffuse infiltrations of lymphocytes and lymphoid clusters.