A study on the immune response of cattle naturally infested with blood parasites and vaccinated with sheep pox vaccine private [electronic resource]

Includes references.

The immune response of naturally infested cattle with Theileria annulata, and vaccinated with sheep pox virus vaccine was studied in comparison with the immunity of vaccinated healthy animals. Fourteen bulls were proved to be susceptible to sheep pox virus vaccination via screening of their sera using serum neutralization test. Six of these animals were confirmed to be infested with theileriosis via examination of Giemsa stained blood smears and immunofluorescent investigation of another blood films. Another six non-infested animals beside the infested one with theileriosis were vaccinated at the same time with sheep pox virus vaccine and two healthy animals were kept as control. Heparinized blood samples were collected for evaluation of the cell mediated immune response using lymphocyte transformation assay and the sera were separated for evaluation of the humoral immunity using serum neutralization double antibody sandwich ELISA and dot immunoblot ELISA techniques. A challenge test using the virulent lumpy skin disease virus was carried out at 90 day post vaccination for evaluating the immune status of all animals. Results revealed a significant decrease in lymphocytic cells in animals infested with theileriosis and the level of lymphocytic cells varied according to the severity of infection. Also, the antibody titres and the challenge with virulent virus showed highly depressed of antibody levels In acute infested animals, partial suppression In chronic infested animals with theileriosis and positive reaction to challenge in severely infected animals and controls. It could be concluded that the degree of theileriosis infestation in cattle should be considered during thc vaccination campaign against lumpy skin disease to avoid the failure of vaccination.

Summary in Arabic.

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