Estratégias nutricionais para bovinos Angus-Nelore recriados em confinamento no período de transição seca-águas e suplementados a pasto no período das águas

Abstract

The objective was to evaluate the effect of the interaction between nutritional plans (moderate vs. high gain) for growing steers in the feedlot during the dry-to-rainy transition period and nutritional strategies (additive mineral supplement vs. protein-energy supplement) on pasture during the rainy season on the growth curve and productive performance of Angus-Nellore cattle. A total of 48 uncastrated ½ blood Angus-Nellore cattle, aged 9 ± 1 months and with an initial body weight of 214 ± 23 kg, were used. The design was completely randomized in a 2 x 2 factorial, with two weight gain rates in the feedlot during the dry-to-rainy transition (moderate gain vs. high gain) and two nutritional strategies on pasture during the rainy season (additive mineral supplement vs. protein-energy supplement). Body weight, average daily gain, and pasture variables were analyzed as repeated measures over time. The animals with higher performance at the end of the feedlot growing phase during the dry-torainy transition gained an additional 30 kg compared to the animals with a lower predetermined gain target. Significant increases in average daily gain, dry matter intake, feed efficiency, crude protein intake, and total digestible nutrient intake were observed for these animals. The high gain strategy (HG) for growing steers in the feedlot, due to higher dry matter intake (DM) and diets richer in energy and protein during the rainy season, promoted higher average daily gain (ADG) and feed efficiency.