Immunization of sheep with whole body of Echinococcus granulosus

In the present study, two hundred mature Echinococcus granulosus, which were kept in 10% formaline for 8 months, obtained from parasitology Depatrment, School of Veterniary Medicine, Ferdowsi University of Mashhad. Protein soluble of parasite was prepared. The sample hemogenized in a blender, sonicated on ice and then centrifugated for 15min at 10000 g. Final yield was kept at -20 º C until used. Eight Lambs 4 – 6 months of age of mixed sex, were divided into 2 groups of 4 lambs. Each lamb in test group was vaccinted subcutaneously in the neck with a 2 ml dose of vaccine [1 mg of whole body of E. granulosus protein dissolved in 1 ml of PBS plus 1 ml of Freund ,s complete adjuvant (FCA)]. Control lambs were vaccinated with adjuvant in PBS. Lambs were re-vaccinated four weeks after the first vaccination with the same preparation except that FCA was replaced by Freund ,s incomplete adjuvant (FIA). Three weeks after the second vaccination, each lamb received a challenge infection with 2000 protoscolices intrapritoneally and 10 adult E. granulosus. All sheep were killed after 7 months and examined for hydatid cysts. Results showed that, in comparison to control lambs, olny in one of the vaccinated lamb two and one cyst were observed in liver and lung respectively. The number of cysts in vaccinted lambs were significantly lower than in control group (P<0.001 ). This result indicated that the protective immunity in sheep with whole body of E. granulosus was approximately 90%.

Keywords:

Echinococcus granulosus , Whole body , Vaccination , Sheep