The objectives of the present study were to develop a methodology that implies the use of an electronic spreadsheet to calculate the financial losses of involuntary days open (IDO; every additional day open beyond an optimal calving-to-conception interval) and to show an example of the cost of days open using the proposed methodology. The costs accounted for in the methodology were: milk yield loss, calf crop loss, additional reproductive interventions, and cow replacement costs due to infertility. An example for Argentinean dairy cows in grazing year-round calving systems is presented. Results suggest that milk yield loss and cow replacement due to infertility are the main components determining the final cost of the delayed pregnancy. The methodology presented in this study is simpler than previous methodologies, and can be applied in a wide range of scenarios, using different cow types and regional costs.
dairy system; day open; financial losses
