Tracheal transcriptional response to challenge with virulent Mycoplasma gallisepticum in chickens spray vaccinated with the Vaxsafe MG304 live-attenuated vaccine

Abstract

The live-attenuated Vaxsafe MG304 (ts-304 strain) vaccine protects against respiratory tract lesions caused by Mycoplasma gallisepticum when it is administered to day-old chicks by aerosol spray in either an aqueous or a gel base. This study used mRNA sequencing to examine transcriptional changes in the tracheal mucosa after challenge with M. gallisepticum in chickens spray vaccinated with Vaxsafe MG304 at one day of age. Chickens vaccinated by spray in an aqueous base at a dose of 107.0 colour changing units did not have significant transcriptional changes, except for down-regulation of the CRHBP (corticotropin-releasing hormone binding protein) gene, in the tracheal mucosa 2 weeks after ch..