Agent-based simulation model to evaluate the economic performance of reproductive programs in beef cattle

Abstract The objective of this study was to create a stochastic, agent-based simulation model to compare the economic performance of reproductive strategies in beef cattle. The model was parameterized using data from a real herd and the scientific literature. The scenarios evaluated were: natural mating (NM) only (ONM); one timed artificial insemination (TAI) plus NM (1TAI+NM); two TAI plus NM, with 24, 32, and 40 days between TAI (2TAI/24+NM, 2TAI/32+NM, and 2TAI/40+NM, respectively); three TAI without NM, with 24, 32, and 40 days (3TAI/24, 3TAI/32, and 3TAI/40, respectively), and three TAI plus NM, with 24 and 32 days (3TAI/24+NM and 3TAI/32+NM, respectively). The initial female herd was 400 and remained constant. The bull population varies from 0 to 15, depending on the scenario. The outcomes for each scenario are assessed on 32 farms, using a 5000-day time horizon at one-day time intervals and an animal-by-animal basis. The 3TAI/24+NM scenario resulted in the highest incomes (US$ 96,479.2 ± 709.8), while ONM had the least value (US$ 79,753.4 ± 741.9). The total operating cost was highest for 3TAI/24+NM (US$ 101,720.6 ± 79.2) and lowest for ONM (US$ 90,898.6 ± 59.2). However, when the total operating cost was evaluated per kg of weaned calf, the highest and lowest costs were for ONM (US$ 2.8 ± 0.0/kg) and 2TAI/24+NM (US$ 2.17 ± 0.0/kg), respectively. The 2TAI/24+NM (US$ -4,651.3 ± 630.7) scenario presented the best net margin, while the lowest result was for 3TAI/40 (US$ -12,590.0 ± 746.3). Our model suggests that reproductive strategies that use TAI have better economic performance than those under ONM. However, when three TAI were performed with 40 days, the benefit was lower, and even for some analyzes, it was worse than the ONM. The 2TAI/24+NM scenario outperformed the others because of the contrast between its high income with moderate costs.