Performance of dairy steers subjected to different food strategies during the growing and finishing phases

The objective of this study was to evaluate the performance of dairy crossbreed steers, in feedlot, previously fed with different supplemented energetic systems and Brachiaria brizantha pasture. The treatments were: TAA - high level intake of energy during the growing and finishing phases; TAM - high intake of energy during the growing phase and medium intake of energy during of the finishing phase; TMA - medium intake of energy during growing phase and high intake of energy during finishing phase; TMM - medium intake of energy during the growing and finishing phases. During the growth phase the animals received supplementation of 1.0% and 0.5% body weight. In the finishing phase, the animals were fed diets containing 50% of concentrate (medium intake of energy, TDN = 71%) or 80% of concentrate (high intake of energy, TDN = 80%) in the dry matter of the total diet. The animals of the TAA and TAM treatments had higher average body weight at the beginning of feedlot due to that achieved average slaughter weights of 42 and 21 days less than the other treatments. The animals of the TAA and TAM treatments had higher dry matter intake (P<0.05), % PV and g/PV0, (75)), average daily gain and feed conversion than the other treatments. The animals supplemented with higher energy level in the growing phase had higher heart girth (P < 0.05) and lower gain of this measure during the feedlot. There was no difference (P > 0.05) between treatments for these measures at the end of the feedlot. The high level of energy supplementation during the growing phase allowed animals to a greater initial weight of the feedlot, and consequently, the best performance.