Modelo bioeconômico para cálculo de custos e receitas em sistemas de produção de gado de corte visando à obtenção de valores econômicos de características produtivas e reprodutivas

Abstract

A bio-economic model was developed to calculate costs and revenues to obtain economic values (EV) for performance traits of beef cattle in production systems in Brazil. Performance records, economic and biologic parameters were obtained from a Nelore breeding herd. Two production systems: complete breeding cycle (CbcR) and cow-calf (Cc) were simulated using a deterministic and static model. Costs, revenues and the annual profits were calculated using Excel® to obtain the economic values for weaning weight (WW), mature weight (MW), pregnancy rate (PR) and weaning rate (WR) in both systems. The impact of changes in genetic level of traits on annual profits of the production systems were evaluated by increasing the original values of the traits by 1%. This increase resulted in positive changes on profits and the greatest impact was for WR in both systems. EV for WW, MW, PR, WR in CbcR and Cc systems were respectively R$ 0.40/kg, R$ 0.09/kg, R$ 3.20/1%; R$ 10.15/1% and R$ 1.31/kg, R$ 0.09/kg, R$ 2.41/1% and R$ 3.36/1%. The bio-economic model satisfactorily described the beef cattle production systems and can be adapted to other production circumstances. © 2006 Sociedade Brasileira de Zootecnia.