Serotyping and prevalence of avian pathogenic Escherichia coli infection in broilers in Kashmir

Among poultry diseases, which cause huge economic loss in terms of mortality and condemnation of carcasses at slaughter houses, avian colibacillosis caused by Escherichia coli (E. coli), is considered as one of the major and principal causes of morbidity and mortality. Present Investigation was aimed at studying the prevalence of colibacillosis in commercial broiler chicken and to identify the most predominant serotype of E. coli in broiler chicken. Samples comprised of mortalities from various poultry farms operating in Srinagar and Ganderbal district along with their adjoining areas. Colibacillosis constituted significant component of mortality among broiler chicken of all age groups ranging from 23.634% to 29.845% with overall mean of 26.357%. The most prevalent serogroup of E. coli observed was O76 (15.59 %), followed by 14.45 % O8, 12.17 % O1, 7.22 % O26, 6.44 % O20, 4.94 % O114, 4.18% O11, 3.80 % O2, and 3.04 % each O45 and O84. However, 15.21% untypeable, and 6.08% rough type were also observed. Impression smears revealed Gram negative, capsulated and cocobacillary organisms. The cultural and biochemical characteristics were characteristic of E. coli.