Prevalence and serological evidence of Mycoplasma gallisepticum among commercial layers

Abstract

Pakistan’s poultry industry, being one of the world’s major chicken producers, is facing economic losses due to a major pathogen Mycoplasma gallisepticum which is the leading cause of Chronic Respiratory Disease (CRD). This study aims to determine the seroprevalence of MG in commercial layer farms (Multan, Muzaffargarh, and DG Khan) in South Punjab, Pakistan. Approximately 400 serum samples were collected for experiment, which revealed 47.9% seroprevalence. Multan exhibited a higher prevalence (50.47%) compared to Muzaffargarh (47.25%) and DG Khan (43.15%). The recorded age-wise seroprevalence of MG infection was higher (50.85%) in younger birds (45–65 weeks old) and lower (45.73%) in birds older than 65 weeks. For seroprevalence, enzyme-linked immunosorbent assay was employed using (IDEXX Mycoplasma gallisepticum antibody test kit). The findings indicated a significant seroprevalence of MG in South Punjab, predominantly in younger birds, which can be attributed to insufficient immunity and vertical transmission. Clinical observations were conjunctivitis, frothy nasal and ocular discharge, reduced egg production, while postmortem findings revealed air sacculitis, pericarditis, and ovarian abnormalities. In conclusion, the strategy for controlling MG seroprevalence should focus on ensuring strict biosecurity measures against contamination and transmission and implementing a controlled and comprehensive national surveillance program against MG infection in Pakistan.