SIMULATION OF DRY-MATTER, CRUDE FIBER AND METABOLIZABLE ENERGY CONSUMPTIONS IN AN EXPERIMENT WITH DAIRY-COWS GRAZING COAST CROSS-1 BERMUDA GRASS (CYNODON-DACTYLON PERS)

From the data of an experiment where the performance of coast cross 1 bermuda grass was studied in the rainy season under a selective grazing system (pointer cows) supplemented with 4 kg/cow/day or without concentrate supplementation, a model for the simulation of dry matter (DM), crude fibre (CF) and metabolizable energy (ME) consumptions was developed. The model obtained describes the DM, CF, and ME availabilities according to pasture height, it estimates the ME requirements and the CF ingestion capacity of the animals and by means of a pasture-animal interphase, it simulates the consumption and the availability in the residue of DM, CF and ME. The validation of the model executed in two variants for estimating DM availability on the indicators where a verification was possible, showed similar results to what was measured, with maximum errors of 7,l %. The model adequately represented the biological situation studied and constitutes a basis for the development of complex models. It also offers potentialities for its utilization in the planification of milk production and pasture management.