Objective: Comparison of the effects of buffalo-originated Echinococcus granulosus egg and onchosphere antigens in
preventing the establishment and development of hydatid cysts in
Design: Clinical trial. Animals: Nine male buffalo calves, 7-8 months of age. Procedure: Collection of E.granulosus from dogs, orally infected
with buffalo-originated viable protoscoleces separation of eggs
from the gravid proglottids , culture of eggs and collection of
activated onchosphcrcs , sonication the eggs and onchospheres and preparation their homogenized antigens, intramuscularly injection of each of these antigens, mixed with complete Freund’s adjuvant (CFA) to two groups of 3 buffaloes, first injection of PBS plus CFA
to controls, second injection, with the same materials to the cases
and controls, after 6 weeks, challenging each case and control with 500 E.granulosus eggs and slaughtering all buffaloes after 10 months. Statistical analysis: Analysis of variance, tukey test.
Results: The numbers of liver and lung hydatid cysts were significantly
smaller than those of controls. Intestinal protection due to egg and onchosphere antigens were 84.5% and 89% respectively. Site
protection of liver and lung against hydatid cyst establishment, achieved by the egg and onchosphere antigens were 45.3/a and
53.37% respectively. Immunological protection due to egg and
onchosphere antigens were 76.7% and 83.5% respectively, too.
Conclusion: Antigens derived from the E. granulosus eggs and
onchosphere arc able to protect buffaloes against hydatidosis
although the protection potential of activated onchosphere antigen is much higher than the egg antigen. J. Fac. Vet. Med Univ. Tehran. 58 2: 187-191 2003.