Survey of antibiotic treatment of Escherichia coli infection in broilers and efficacy of Enrofloxacin plus colistin in experimental Colibacillosis

摘要

Colibacillosis caused by Escherichia coli is very important disease of poultry and is characterized by development of colisepticemia, pericarditis, perihepatitis, increased mortality and decreased feed conversion rate. Thirty E. coli infected broiler farms located in district Faisalabad were surveyed and data pertaining to antibiotic usage, storage, withdrawal period and farmers perception on antibiotic resistance was obtained. Data showed that most of poultry farmers used antibiotics in combination (Enrofloxacin plus colistin) to treat or control E. coli infection. Morbid samples from suspected E. coli infected birds were collected, pure colonies of were isolated and pathogenicity was determined. In vivo colibacillosis in broilers was induced by oral inoculation of 1×10 6 colony forming units (cfu)/bird and efficacy of enrofloxacin plus colistin was determined. For that purpose one hundred forty (140) broiler birds were divided into four groups (A, B, C and D), each having 35 birds. At 26 th day of age E. coli infection was induced in all groups. At 28 th day of age group A was treated with enrofloxacin plus colistin sulphate, group B with enrofloxacin, group C with colistin sulphate and group D was kept as untreated control. Mortality, cumulative feed consumption, mean body weight, mean weight gain and FCR were recorded in each group. It was found that combined use of enrofloxacin plus colistin in colibacillosis in broilers decreased mortality, increased cumulative feed consumption, increased mean body weight, increased mean weight gain and FCR than single use of either of enrofloxacin or colistin.