STUDIES ON THE DEVELOPMENT AND USE OF A MONOCLONAL SANDWICH ELISA FORTHE DETECTION OF VEROTOXIC ESCHERICHIA-COLI IN ANIMAL FECES

A sandwich ELISA using monoclonal antibodies to Escherichia coli veroc ytotoxins 1 and 2 for capture and detection was developed for detectio n of verocytotoxin-producing Escherichia coli (VTEC) in animal faeces, For optimal toxin detection, the faeces were cultured in MacConkey br oth before subculture on to trypticase soy agar containing mitomycin C . It was possible to detect between 10 and 10(3) VT1-producing and 1 t o 10 VT2-producing E coli/g faeces, and overall the sensitivity and sp ecificity of the ELISA for VTEC in faeces were 80.5 per cent and 91.2 per cent, respectively, when compared with a verocell assay, A limited survey of faeces from healthy animals (89 cattle, 16 sheep, 22 pigs, 11 goats and six domestic fowl) and faeces from 144 cattle with enteri c disease detected VTEC in 64 per cent, 63 per cent, 5 per cent, 45 pe r cent, none and 16 per cent of the samples, respectively.