Isolation and Phylogenetic Analysis of Avian Mycoplasmas from Poultry Affected with Respiratory Infections in India

Abstract

Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS) are the two most pathogenic avian mycoplasmas. In the present study, examination of 92 pooled tissue samples from broiler chicken of 92 different poultry flocks of Haryana (India) exhibiting respiratory infections resulted in isolation of 13 (14%) Mollicutes. Based on biochemical reactions, growth inhibition test, PCR and/or sequencing, 8 (8.6%) isolates could be characterized as MG, 1 (1.08%) as MS, 3 (3.24%) as M. gallinarum and 1 (1.08%) as Acholeplasma laidlawii. The phylogenetic analysis using Intergenic spacer region (IGSR) of these MG isolates revealed that they clustered with USA strain whereas the vaccine strains were in different clade. Single locus sequence typing (SLST) revealed considerable nucleotides variation between 8 MG isolates and vaccine strains. Conclusively, Sequencing of IGSR region of MG can be used as a valuable epidemiological investigation tool for the differentiation of wild-type MG strains from vaccine strains.