Economic assessment of Ostertagia ostertagi and Fasciola hepatica infections in dairy cattle herds in Germany using Paracalc®.

The aim of the current study was to estimate economic costs of Ostertagia ostertagi and Fasciola hepatica infections in dairy cattle herds in Germany using the online calculation programme Paracalc®. Following a questionnaire, survey data were available from 464 farms in 14 federal states. On those farms bulk tank milk (BTM) samples and additionally up to six serum samples collected from first season grazing calves were analysed, using a commercially available ELISA (Boehringer Ingelheim SVANOVA Biotech AB, Uppsala, Sweden), an in-house ELISA (F. hepatica) and an in-house serum pepsinogen test. In total, samples obtained from 344 farms were included in the analysis since those were the only farms with complete questionnaires. Median costs per farm and year were estimated for gastrointestinal (GI) nematode infections (€721.38) and F. hepatica infection (€565.61). Decreases in milk yield in multiparous cows were the major reason for annual production losses due to GI nematodes (€13.33 per cow) and F. hepatica infections (€7.95 per cow), which was followed by annual costs for anthelmintic treatment against GI nematode infections in adult cows (€10.00 per cow) and F. hepatica infection associated annual costs due to repeated artificial insemination (€10.13 per cow) and prolonged calving intervals (€9.40 per cow). The study demonstrated that if all required information is provided, the Paracalc® tool can assist to identify productions losses in dairy cattle herds due to helminth infections and to optimise farm economics in Germany.