Impact of trichomoniasis on the cow-calf producer's profitability.

Using current knowledge of bovine trichomoniasis, a computer spreadsheet simulation model was developed to contribute to the understanding of the disease dynamics and the disease's impact on calf crop, weaner calf production, and revenue returns. Two disease prevalence simulations were generated with the model. In each simulation, 200 susceptible cows were confined with 5 fertile bulls. In simulation 1, one bull was infected with Tritrichomonas foetus (prevalence, 20%); in simulation 2, 2 bulls were infected (prevalence, 40%). The remaining bulls in these groups were designated noninfected. The disease simulation outcomes for breeding and calving variables were compared with a similar but noninfected model group, simulation 0. The disease model predicted a reduction of 14 to 50% in annual calf crop, a prolonged breeding season, a reduction of 5 to 12% in the suckling/growing period, a reduction of 4 to 10% in pounds of marketable calf crop at weaning, a reduction of 4 to 10% in monetary return per calf born, and a substantial reduction of 5 to 35% in the return per cow confined with a fertile bull.