Evaluation of latex agglutination (LAT) and indirect haemagglutination (IHA) techniques to detect sheep dicrocoeliosis

Dicrocoeliasis caused by the small liver fluke Dicrocoelium dendriticum which live in the bile ducts and gall bladder of wild and domesticated mammals, particularly ruminant. Immunodiagnostic methods are useful for early diagnosis.
The purpose of this study was evaluation of agglutination latex (LAT) and indirect haemagglutination (IHA) tests for diagnosis of Dicrocoelium dendriticum infection in sheep.
Adult worms were collected from infected livers of sheep at a local abattoir. The excretory-secretory and somatic antigens were prepared through homogenization and sonication. Infected sheep with Dicrocoelium dendriticum and non-infected lambs were bleeded to providing positive and negative serum. Somatic and excretory-secretory antigens were added and blended to latex particles. All samples of positive and negative serum were added to latex and considered according to agglutination reaction. In IHA, the sensitive RBC and somatic and ES antigens were added and blended and haemagglutination was evaluated .
The sensitivity and specificity of LAT by excretory secretory antigen were 84% and 97/6% and by somatic antigen were 96% and 97/6%, respectively. The sensitivity and specificity of IHA by excretory secretory antigen were 60% and 92/9%, and bysomatic antigen were 92% and 66/7%, respectively.
According to present study, the LAT test by excretory secretory antigen and somatic has high sensitivity and specificity, and it is a quick test and without need to special tools for diagnosis of dicrocoeliosis.