author(s)
M Veeraselvam, NR Senthilkumar, S Vairamuthu and V Ramakrishnan

abstract
The present research work was undertaken for the isolation and identification of the etiological agents present in the respiratory tract of infected native chicken. Totally of 276 samples were collected from infected native chickens from various locations of Salem district, Tamil Nadu, India. The samples were nasal, conjunctiva and tracheal swabs. Twenty three of these collected samples did not show any bacterial growth in any type of growth media despite of the clear clinical respiratory symptoms. The remaining 253 samples gave 337 isolates, 258 (76.5%) of them were Gram negative bacteria, and the rest 79 (23.4%) isolates were Gram positive bacteria. The 337 isolates were 23 (6.82%) Pseudomonas species, 116 (34.42%) E. coli species, 14 (4.15%) Klebsiella species, 51 (15.13%) Pasteurella Species, 79 (23.4%) Staphylococcus species and 54 (16.0%) Salmonella species. Motility test and biochemical test viz. sugar fermentation test, indole test, Methyl red (MR) test, Voges-proskauer (VP) test, Triple sugar iron (TSI) test, catalase and coagulase tests were performed to differentiate motility and identification of isolated bacteria. Our findings will help to understand the bacterial organisms associated with respiratory distress in native chickens.