Performance of Modified Agglutination Test (MAT) in serodiagnosis of Sarcocystis cruzi (Sarcocystis bovicanis) and Sarcocystis hirsuta (Sarcocystis bovifelis) in cattle was evaluated with reference to agar gel precipitation test (AGPT), counter immunoelectrophoresis (CIEP) and indirect haemagglutination test (IHAT). MAT performed in rabbit sera hyperimmune to crude antigens of S. cruzi and S. hirsuta showed positive result against homologous and heterologous antigens similar to those observed in AGPT, CIEP and IHAT. Formalin killed whole bradyzoites of S. hirsuta used as antigen also detected antibodies in sera of 88.33% open grazing cattle by MAT while similar S. cruzi antigen could detect antibodies in 81.25% of tested sera samples. Crude soluble antigens of S. hirsuta coated on tanned sheep red blood cells detected antibodies to Sarcocystis in 85% of tested sera of cattle against 82.14% detection with S. cruzi antigen in IHAT. However, the AGPT and CIEP results were negative when employed in field sera of cattle. The results of MAT and IHAT in hyperimmune rabbit sera and cattle sera were comparable with evidence of cross reactivity between the two parasite species. MAT thus proved reliable and as effective as IHAT for seroprevalence study of Sarcocystis infection.
