intestinalis larvae found in their stomachs and also the lack of significant differences in the intensity of reaction of the IgA antibody against G. intestinalis in the saliva, observed between the horses in whose case low infection intensity was observed (10–50 larvae), and the horses free from any invasion, seem to be interesting from the point of view of diagnostic usefulness of this method in detecting high burden horses. The gene discussed is CD79A; the disease is infection.