Biotin-streptavidin enzyme-linked immunosorbent assay for the detection ofantibodies to Campylobacter jejuni and C-coli in chickens

An enzyme-linked immunosorbent assay (ELISA) was developed in a homologous system with bacterial ultrasonic-treated proteins as the antigen and antise ra from chickens infected orally and subcutaneously with the strain Campylo bacter jejuni serovar 6 (CJ 6). The cut-off level was determined using anti sera from non-infected specific-pathogen-free chickens up to the age of 10 weeks. The suitability of the ELISA system was verified using antisera take n from chickens orally infected at the age of 4 weeks with CJ 1, 6, 28 or 3 6 or with Campylobacter coli serovar 28 (CC 28). The development of antibod ies was monitored up to 6 weeks post-infection (p.i.). Sera from chickens i nfected with CJ 1, 6, 36 or CC 28 contained specific antibodies to Campylob acter; whereas in those infected with CI 28 no specific antibodies were fou nd. Distinct cross-reactions were observed between CI 6, 28 and CC 28 antig ens and their antisera 6 weeks p.i., while poor cross-reactions were found with antisera to CI 1 and 28. Antibodies to strains of all heterologous ser ovars were successfully detected with an antigen pool comprised of CJ 1, 6 and 36 antigens. In 11 our of the 12 field sera obtained from 5- and 9-week -old broiler chickens suffering from campylobacteriosis, high specific anti body titres to Campylobacter jejuni were found.