Cinetica di ceppi vaccinali del virus della bronchite infettiva e interazioni con ceppi di campo e Metapneumovirus aviare in allevamenti di broiler

Infectious bronchitis (IB) control is managed through biosecurity measures and vaccine administration. In Italy vaccination has been performed as an association of two genotypes, Mass and 793B-like, following the protectotype concept. Initially the vaccine administration was given in two distinct moments, 14 days apart, while recently both vaccines have been provided at first day of life. To evaluate the vaccine kinetic, 237 samples have been analysed by two different real-time RT-PCR specific for Mass-like and 1/96 (IBird®, CEVA). Samples have also been processed for IBV field strains detection and sequencing and aMPV screening. Vaccine kinetic showed a similar trend between the two strains, with long persistence and an analogous decline through the production cycle. 1/96 strain appeared to be slightly more protective than Mass-like ones and the detected field strains (QX, 793B, Q1) emerged mainly during the last period, such as subtype B aMPV positivities. IBV field strains and aMPV coinfections have been detected.