Protección contra babesiosis bovina con una vacuna mixta de Babesia bovis y Babesia bigemina derivada de cultivo in vitro bajo una confrontación de campo...
In Mexico, there is an attenuated live vaccine against bovine babesiosis that has been shown to conferprotection to susceptible cattle immunized and challenged under controlled conditions. Immunized cattlesurvive a challenge using known numbers of virulent parasites of both Babesia bovis and Babesia...
| Autores: | , , , , , , |
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| Tipo de documento: | artigo |
| Estado: | Versão publicada |
| Data de publicação: | 2003 |
| País: | México |
| Recursos: | Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias |
| Repositório: | Redalyc-INIFAP |
| OAI Identifier: | oai:redalyc.org:42334403 |
| Acesso em linha: | https://www.redalyc.org/articulo.oa?id=42334403 |
| Access Level: | Acceso aberto |
| Palavra-chave: | Veterinaria IMMUNIZATION BABESIA BOVIS BABESIA BIGEMINA |
| Resumo: | In Mexico, there is an attenuated live vaccine against bovine babesiosis that has been shown to conferprotection to susceptible cattle immunized and challenged under controlled conditions. Immunized cattlesurvive a challenge using known numbers of virulent parasites of both Babesia bovis and Babesia bigemina.However, stress-inducing field situations such as transportation or tick-transmitted infection have not beentaken into account. The objective of this study was to evaluate the protective capacity of the combined vaccinein cattle immunized in a tick-free area and then transported to an endemic area. Ten, 18 month old, susceptibleCharolais steers were divided into two groups: one group was immunized with 1 × 107 erythrocytes infectedwith in vitro culture-derived Babesia bovis and Babesia bigemina parasites; while the second group wasimmunized with uninfected bovine erythrocytes. Two months later, both groups were transferred to a bovinebabesiosis endemic area and allocated in a corral infested with Babesia-infected Boophilus microplus ticks.Animals remained there for the rest of the experiment and never received ixodicide treatment. Eighteen dayspost-allocation, all five control animals presented with severe clinical signs characteristic of acute bovinebabesiosis, including a rectal temperature (RT) greater than 40.5oC for several days and a decreased packed cellvolume (PCV) of 48%. Both protozoan species were found in blood smears and all animals in the control grouphad to be treated in order to avoid their demise. The immunized cattle also presented both Babesia species inperipheral blood samples, increased RT and a 37% PCV reduction, but remained in good corporal condition and did not require treatment. This study shows the protective capacity conferred to cattle by the combinedvaccine when immunized in a Babesia-free area and then transported to an endemic area. |
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