Prevalence of antibodies to 'Mycoplasma synoviae' in laying hens and possible effects on egg shell quality

Abstract

'Mycoplasma synoviae' ('M. synoviae') can cause respiratory disease, synovitis, or result in a silent infection in chickens and turkeys. The importance of 'M. synoviae' is well established in broilers but only a few studies have been conducted in layers. In the present study, the prevalence of 'M. synoviae' in commercial layer flocks was estimated using ELISA. For this study, 19 commercial layer flocks were selected randomly from New South Wales and Queensland region of Australia from producers who were willing to participate in the survey. Sixty eggs per flocks were randomly collected, out of these 30 eggs were used for ELISA and remaining 30 eggs were used to estimate various egg shell quality parameters. Subsequently, association between the serological status of eggs for 'M. synoviae' and egg shell quality was studied. In the flocks under study, seroprevalence of 'M. synoviae' was found to be high at 69% (95% confidence interval (CI) = 41.3-89.0). Statistical analysis showed an association between serological status for 'M. synoviae' and egg quality parameters such as translucency, shell breaking strength, % shell reflectivity and shell deformation. On the other hand, there was no significant association between serological status for 'M. synoviae' and other egg quality parameters such egg weight, egg shell weight, % egg shell or shell thickness.