Systems Analysis for Designing Reproductive Management Programs to Increase Production and Profit in Dairy Herds

Abstract Relative economic merits of three heat detection rates and three conception rates were evaluated by mathematical modeling and dynamic simulation. Three heat detection programs evaluated were: a) poor, with no specific time set aside for detection and detection rate of .35; b) average, with two 45-min observations each day and detection rate of .55; c) good, with three 45-min observations each day and detection rate of .75. Changing heat detection program from poor to average and average to good decreased days open from 136 to 119 and to 105. Corresponding increases in net return per cow per year were $60 and $4. Three breeding programs evaluated were: a) poor, direct service by an inexperienced inseminator and conception rate of .42; b) average, professional artificial inseminator servicing the cows with a single insemination at each service and conception rate of .50; c) good, professional artificial inseminator using two inseminations during each service period and conception rate of .58. Changing breeding program from poor to average and average to good decreased days open from 123 to 119 and to 115. Corresponding changes in net return per cow per year were an increase of $39 and a decrease of $7.

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