Molecular detection of respiratory avian mycoplasmosis associated bacterial and viral concurrent infections in the poultry flocks

Respiratory tract infections are of serious concern to the poultry industry. The present study was aimed to delineate the extent of respiratory avian mycoplasmosis associated bacterial and viral concurrent infections in the poultry flocks. A total of 146 poultry flocks of Haryana and Rajasthan, India, suspected for chronic respiratory disease (CRD) were screened for avian mycoplasmas, Newcastle disease virus (NDV), infectious bronchitis virus (IBV), and avian pathogenic Escherichia coli (APEC) by conventional polymerase chain reaction (PCR) assays. A total of 49.31% (72/146) flocks were found positive for Mycoplasma infection. Of the Mycoplasma-positive flocks, 80.55% (58/72) represented pathogenic avian mycoplasmas (MG and/or MS), while 19.44% (14/72) flocks were positive for commensal avian mycoplasmas (other than MG and MS). A correlation was deduced between avian mycoplasmosis and bacterial and/or viral co-infections. The results revealed that 17.24% (10/58) flocks had only avian mycoplasmosis infection. However, in the remaining flocks, the avian mycoplasmosis was associated either with APEC infection [17.24% (10/58)], IBV infection [43.10% (25/58)], or both APEC and IBV infections [22.41% (13/58)], respectively. Further epidemiological studies on respiratory avian mycoplasmosis associated concurrent infections with other pathogens are recommended to assess circulating strains, risk factors, and economic losses.