A stochastic dynamic model was used to evaluate the effects of price and management changes on optimal decisions for replacement and insemination. A simulation was used to determine the added value of optimized decisions over benefits from typical recommendations. Five levels were specified for each input. Inputs were varied individually and then placed into price or management categories and varied as groups. Five price levels and five management levels were defined. All 25 possible combinations of price and management level were examined. One combination represented typical Florida inputs and was used as a base run. The variation of model outputs resulting from the uncertainty in specifying inputs was used to determine which results represented meaningful change from the base run. Varying inputs individually rarely caused meaningful changes in optimal policy with the exception of pregnancy rate. However, varying inputs in price and management groups consistently resulted in meaningful changes in optimal policies. In addition, interactions between price and management level were important. Just as optimal replacement and insemination policies changed with different decision contexts, the value of these policies also changed. Results make it readily apparent that replacement and insemination policies should be specific to a given situation.
Key words
optimization
insemination
replacement
economic analysis
Abbreviation key
BA
behavioral analysis
CR
conception rate
DP
dynamic programming
ED
estrus detection
ML
management level
MOL
month of lactation
PL
price level
SA
sensitivity analysis
V1
net present value accumulated over the decision horizon of a first parity cow and her replacements by month of calving