Prevalence of E. coli serovars in broiler farms: Biosecurity and the disinfectants sensitivity in Egypt

This study was conducted to evaluate the degree of biosecurity level with especial reference to E. coli Spp as an example to explain the expected causes and risk factors that leads to spread them in poultry flocks in Egypt and to evaluate  its sensitivity to most common disinfectants used in Egypt. About 300 samples (100 cloacal swabs, 100 liver and intestinal samples,100 litter samples) were collected from 10 broiler farms with different age (at 0 old day, one week,2,4 and 6 weeks of age). The samples were investigated for E. coli Spp and subsequently identified based on biochemical and serological tests. The obtained results showed that 44 isolates were isolated (27±1.99%) ;(11±0.42%) and (7±0.72%) from cloacal swab; liver and litter, respectively. Mean prevalence of E. coli spp. was 15±1.22%. E. coli serotypes were: O78 (31.81%), O2: H6 (18.18), O1: H7 (15.9), O91: H21(11.36), O128: H2 (9.09), O26: H11(4.54) O146: H21, O124, O44: H18 and O153: H2. The most common serovars were O124, O44: H18 and O153: H2 (2.27%). In absence of organic matter; there was great statistical significant difference in the sensitivity of E. coli  to the most common disinfectants(P<0.05) as Verkon- S® achieved 3 log reduction, after 5-minute,Formalin and Phenique were achieved 4 log and 3log reductions respectively , Aldekol Des- Gda® achieved 4 log reduction, TH4®,Biosentry® 904 and Iodophore achieved 2 log reductions after 5 minutes.