The basis for deciding to replace a dairy cow that produces several lactation periods in cattle, with a heifer that has recently experienced its first calving, is the comparison of the present values of these two cases. In order to estimate the expected statistics under the optimized policy, Markov chain simulation as a dynamic programming was used. The objective function was to maximize the present net value of cows in a planning horizon with 10 lactation periods. It was observed that with increasing the calving interval, the future value is less produced from the ideal condition that originates from increasing the probability of involuntary culling that intensifies with age. Meanwhile, according to the results, with cow growth, its future value decreases. Therefore, it can be said that future value changes with age, production level, and lactation period.
Keywords: present value, future value, replacement and culling, dynamic programming, dairy cow
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