Abstract

A simulation model was developed to predict growth rate and days required to reach target mating weight of dairy cattle heifers in a stall-feeding system. Input parameters for the model are gross energy (GE), ash, crude protein (CP), organic matter digestibility (OMD), dry matter (DM), protein degradation variables and heifer initial body weight. Based on these inputs, the model calculates metabolisable energy (ME) and metabolisable protein (MP) that re used to simulate weight gain. Results indicate  that growth rate of heifers fed elephant grass as sole feed can be predicted by forage characteristics. Since decisions about heifer management influence future profitability in smallholder dairying, the results of this study are valuable in that being able to predict the growth of heifers can be crucial in providing insight for appropriate intervention.

Key words:  Models, weight gain, heifers, elephant grass,  simulation.