Antibodies to bovine viral diarrhoea virus (BVDV) in water buffalo (Bubalus bubalis) and cattle from the Northern Territory of Australia

BackgroundFarmed and feral water buffaloes (Bubalusbubalis) populations often coexist with cattle in the Northern Territory of Australia, but their level of exposure to bovine viral diarrhoea virus (BVDV) is unknown. MethodsWater buffalo (n=245) and cattle (n=184) serum samples were collected by the NT Government as part of an ongoing disease surveillance scheme at varying intervals between 1993 and 2001. All samples were frozen and stored at -80 degrees C until testing. Water buffalo samples from farming properties were identified as farmed' animals and the remaining samples as feral' populations. Serum samples were analysed using commercially available ELISAs to test for the presence of BVDV antibodies. ResultsTesting of historical water buffalo sera for BVDV antibodies revealed a low level of exposure, with 4.5% (95% CI 2.6%) being sero-positive; cattle from the same geographical area and time period had higher levels of exposure at 74.5% (95% CI +/- 6.3%). Discussion This survey showed that water buffalo are susceptible to infection with BVDV. No persistently infected water buffalo were identified in this study.