AIM: seroprevalence in two dairy herds. METHODS: seropositive replacement calves and to eliminate the disease from the herd over time. RESULTS: antibody ELISA to identify congenitally infected calves was of economic benefit when the proportion of seropositive replacement calves was > 2.87%. A sensitivity analysis showed that the cost of heifer rearing had the greatest impact on the break-even point, followed by the cost of the initial test. CONCLUSION AND CLINICAL RELEVANCE: rather than persistently infected animals.
Velsen et al. (Wed,) studied this question.