RESUMEN

A modified-live vaccine has been shown previously to prevent fetal infection with bovine viral diarrhoea virus (BVDV)-2 and, to some extent BVDV-1, when used in association with an inactivated vaccine in a two-step vaccination protocol. In this challenge study, the modified-live vaccine used alone was able to protect 13 heifers between 49 and 96 days of gestation at challenge from leucopenia and virus replication and, for a 4-month period, to prevent fetal infection. The efficacy of the BVDV-1f 22146/Han81 challenge was demonstrated by virus isolation from the fetuses of all nine non-vaccinated, control heifers. However, the small number of heifers tested meant that the vaccination failure rate could be as high as 10% in the field.

Asunto(s)

Diarrea Mucosa Bovina Viral/prevención & control , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Enfermedades Fetales/veterinaria , Transmisión Vertical de Enfermedad Infecciosa/veterinaria , Vacunación/veterinaria , Vacunas Virales/administración & dosificación , Animales , Diarrea Mucosa Bovina Viral/transmisión , Bovinos , Relación Dosis-Respuesta a Droga , Femenino , Enfermedades Fetales/prevención & control , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Embarazo , Vacunas Atenuadas/administración & dosificación