Serological methods have increasingly been used for the detection of invasive Salmonella serotypes including enteritidis in poultry. Different types of ELISA, particularly indirect or double antibody-blocking assays using a variety of antigens such as lipopolysaccharide, flagella and SEF14 fimbrial antigen are used as part of control programmes in a number of countries. There are many advantages to using such assays for preliminary screening of flocks prior to using bacteriological culture methods.