RESUMO
Attenuated strains of Babesia bovis and B. bigemina and a strain of Anaplasma centrale were evaluated as immunogens against tick-borne disease. The immunization process was shown to be inocuous, immunogenic and efficient to protect cattle, at least against the babesias. Vaccinated animals proved to be protected when naturally challenged with heterologous and virulent strains, in contrast to control animals that showed clinical symptoms of the disease and had to be treated. The Anaplasma marginale challenge was not efficient since treatment was not necessary in the control animals, therefore it was not possible to conclude that immunization with A. centrale protected animals against anaplasmosis.
Neste trabalho foram avaliadas cepas atenuadas de Babesia bovis e B. bigemina e Anaplasma centrale como imunógenos a serem utilizados no controle da Tristeza Parasitária Bovina. O processo de imunização demonstrou ser inócuo, imunogênico e eficiente, pelo menos no que diz respeito às babesias, pois protegeu os animais vacinados frente ao desafio com cepas heterólogas virulentas a campo, que provocou doença clínica e morte nos animais do grupo controle. O desafio a campo pelo Anaplasma marginale não se mostrou muito virulento ou patogênico, não sendo possível concluir que a imunização com A. centrale proteja os animais contra anaplasmose.
RESUMO
Attenuated strains of Babesia bovis and B. bigemina and a strain of Anaplasma centrale were evaluated as immunogens against tick-borne disease. The immunization process was shown to be inocuous, immunogenic and efficient to protect cattle, at least against the babesias. Vaccinated animals proved to be protected when naturally challenged with heterologous and virulent strains, in contrast to control animals that showed clinical symptoms of the disease and had to be treated. The Anaplasma marginale challenge was not efficient since treatment was not necessary in the control animals, therefore it was not possible to conclude that immunization with A. centrale protected animals against anaplasmosis.
Neste trabalho foram avaliadas cepas atenuadas de Babesia bovis e B. bigemina e Anaplasma centrale como imunógenos a serem utilizados no controle da Tristeza Parasitária Bovina. O processo de imunização demonstrou ser inócuo, imunogênico e eficiente, pelo menos no que diz respeito às babesias, pois protegeu os animais vacinados frente ao desafio com cepas heterólogas virulentas a campo, que provocou doença clínica e morte nos animais do grupo controle. O desafio a campo pelo Anaplasma marginale não se mostrou muito virulento ou patogênico, não sendo possível concluir que a imunização com A. centrale proteja os animais contra anaplasmose.