Comparative studies on the efficacy of Mycoplasma gallisepticum bacterin and tiamulin treatment of breeder layers

摘要

Mycoplasma gallisepticum infection is still a major problem in many breeder layer flocks in the world. Apart from causing respiratory disease and increased mortality of hens, its chronic effects can be depression of egg production, reduced hatchability from increased embryo mortality and the chicks are subsequently infected (Kleven, 1990). Mycoplasma gallisepticum bacterins have been used to increase immunity in the hen. However, these have proven only partially effective.