RESUMEN
Bovine trichomonosis (BT) is a sexually transmitted disease of cattle caused by infection with Tritrichomonas foetus. In a recent study, T. foetus infection was detected in 41.5% of herds of an endangered beef breed, the Asturiana de la Montaña (AM), which is farmed under extensive, mountain pastoral systems in northern Spain. The objective of this study was to determine the prevalence of this pathogen in the more production-centred Asturiana de los Valles (AV) beef breed farmed in the same region, and to identify potential associated management risk factors. Infection was detected in a significantly smaller number (5.2%) of AV herds, despite the fact that both populations share the same ecological niche. Communal grazing was not identified as significant risk factor and study results suggest the prevalence of BT is likely to vary considerably depending on how the cattle are managed.