Evaluation of Respiratory Lesions in Chickens Induced by Mycoplasma gallisepticum

Abstract

A histopathological screening method was developed to evaluate vaccinal effects on Mycoplasma gallisepticum (MG) infection in chickens. Lesions in the tracheal mucosa were graded by scoring, and mucosal thicknesses were measured and used as an indicator representing the degrees of lesions. There was a close relation between the lesion score and mucosal thickness when examined in vaccinated and challenged or unvaccinated and challenged chickens. The measurements of mucosal thickness in the trachea seemed to be a simple and objective method to estimate the degrees of lesions induced by MG infection.