Economic values, genetic gains and economic contributions of a selection index for Romosinuano Creole cattle

The objective of this study was to estimate economic values (ev), genetic gains (gg), and economic contributions (ec) of age at first calving (AFC), calving interval (CI), longevity (LONG), weaning weight (WW), weight at 16 months (W16), and weight at 24 months (W24) within a selection index for the Romosinuano breed. Three production scenarios were evaluated according to the selling age of animals (8, 16, and 24 months). Productive and reproductive parameters were obtained from records provided by AGROSAVIA between 1976 and 2021, while economic information was collected using a structured format designed to characterize production systems. The ev were calculated as the partial derivative of profit per hectare, and ec were derived from gg and ev. Profit per hectare was 239.7, 198.41, and 294.95 USD in scenarios 1, 2, and 3, respectively. CI showed the most relevant ev in scenarios 1 (-0.794 USD) and 3 (-0.979 USD), whereas W16 had the greatest economic value in scenario 2 (1.05 USD). AFC showed negative values across the three scenarios, in contrast to LONG, which presented positive values and considerable ec (0.56, 0.34, and 0.77 USD). Furthermore, WW and AFC were important in scenario 1, while W16 and W24 were relevant in scenarios 2 and 3. In conclusion, CI was confirmed as the trait with the greatest economic impact, whereas W16 and AFC were identified as relevant traits to be included in balanced selection indices. Also, the contribution of LONG highlights the role of Romosinuano cattle in resilient and sustainable Colombian beef production systems.