[Evaluation of three commercial ELISA test kits for the detection of antibodies against Salmonella enteritidis].

We evaluated three commercial enzyme-linked immunoassay (ELISA) test-kits, using either lipopolysaccharide (LPS) or flagellar extracts as antigens, for the demonstration of Salmonella enteritidis (S. e.) antibodies in serum and egg yolk. They were also compared with conventional serological tests, such as the pullorum rapid slide agglutination test (RST), the pullorum slow agglutination tube test and a rapid slide agglutination test, using gm flagellar extracts as antigen. We tested sera and eggs from six different layer flocks. In 84.1 to 90% of the sera and egg yolks tested the three commercial ELISA test kits gave comparable results. There were a number of serological cross-reaction with other serovars, particularly S. typhimurium. However, the possibility of infections with more than one salmonella serovar, other than S. e., cannot be excluded. The ELISA-antibody levels in serum and egg yolk ran parallel and were still high after one year. However, the level of egg yolk antibodies was on an average 33.9% lower than in serum. The S. e.-ELISA seems to be well suited for epidemiological investigations and for preventive and control measures.