Biotin-streptavidin enzyme-linked immunosorbent assay for the detection of antibodies 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 antisera from chickens infected orally and subcutaneously with the strain Campylobacter jejuni serovar 6 (CJ 6). The cut-off level was determined using antisera from non-infected specific-pathogen-free chickens up to the age of 10 weeks. The suitability of the ELISA system was verified using antisera taken from chickens orally infected at the age of 4 weeks with CJ 1, 6, 28 or 36 or with Campylobacter coli serovar 28 (CC 28). The development of antibodies was monitored up to 6 weeks post-infection (p.i.). Sera from chickens infected with CJ 1, 6, 36 or CC 28 contained specific antibodies to Campylobacter; whereas in those infected with CI 28 no specific antibodies were found. Distinct cross-reactions were observed between CI 6, 28 and CC 28 antigens 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 serovars 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 antibody titres to Campylobacter jejuni were found.