Abstract: Mycoplamosis is one of the most important health hazards being faced by the poultry industry of Pakistan. This study was designed to rule out the prevalence of Mycoplasma gallisepticum (MG) in layer flocks of District Faisalabad of Pakistan during a period of one year from January to December, 2010. A total of 640 sera samples were collected from 81 commercial layer flocks with complaint of respiratory distress. On the basis of serum plate agglutination test, 40 flocks were found positive for MG indicating a share of 49.01% among the respiratory diseases. Among 40 positive flocks for MG the highest prevalence (54.84 %) was found in pullets, followed by 46.34 %, and 44.44% in adult and old laying flocks, respectively. Similarly, seroprevalence was also higher (49.01%) in pullets as compared to old layers (28.71%). The disease was more prevalent in winter season (45.13 %) in comparison with the summer season (36.30 %). With respect to flocking density, the higher prevalence rate (48.11%) was recorded in flocks having high bird density as compared to those with lower one (27.27 %).
Keywords: Seroprevalence, Mycoplasmosis, Layers, Faisalabad, Pakistan.