VALIAÇÃO DO EFEITO DE DIFERENTES SUPLEMENTOS NO DESEMPENHO DE NOVILHAS DE CORTE NO PERÍODO CHUVOSO

Abstract

The aim of this study was to evaluate the impact of three supplementation strategies during the rearing phase of heifers raised on pasture in the rainy season. The objective was to determine the influence of these diets on weight gain and feed efficiency in extensive systems. The experiment was conducted using a split-plot design over time (4×3), where the main plots consisted of the experimental days (0, 15, 30, and 45 days) and the subplots were the three supplementation treatments (Total Diet (TD), Blond 200 (BD), and Mineral UP (MU)), with 18 blocks. There was no interaction between the experimental days and the supplementation types for weight gain; however, an interaction was observed for average daily gain (ADG). A quadratic adjustment was observed for both the heifers weight and for average daily gain (ADG). The heifers supplemented with TD exhibited the best performance, starting at 258.94 kg and reaching 303.72 kg after 45 days, with a total gain of 44.78 kg and an ADG of 0.995 kg/day. In the MU treatment, the animals increased from 262.66 kg to 293.33 kg, resulting in a gain of 30.67 kg and an ADG of 0.682 kg/day. Meanwhile, the heifers in theBD treatment started at 256.16 kg and finished at 281.44 kg, totaling a gain of 25.28 kg and an ADG of 0.562 kg/day. In addition to weight parameters, fecal scores and feeder scores were analyzed. TD showed a fecal score of 3.02, which is closer to the ideal, while BD and MU obtained scores of 2.90 and 2.91, respectively. Regarding the feeder score, TD recorded 2.01, indicating complete intake and greater satiety, whereas BD and MU exhibited higher scores (2.69 and 2.66), suggesting lower efficiency in feed intake. The results indicate that supplementation with the Total Diet was the most effective in optimizing weight gain, while the BD and MU treatments, despite some positive aspects, did not achieve the same level of performance.