Viabilidade econômica de sistemas de recria de novilhas de corte em pastagem nativa melhorada no Bioma Pampa

Abstract

The aim of this study was to evaluate the viability of beef heifer’s production as a function of the intensification levels of forage production in native grassland of the Pampa biome. The following treatments were evaluated: Native grassland (Control) native grassland + liming + phosphorus and potassium fertilization (Fertilization) native grassland + liming + phosphorus and potassium fertilization + Italian ryegrass + vesicle clover + red clover (Legumes) native grassland + liming + phosphorus and potassium fertilization + Italian ryegrass + nitrogen fertilization (Nitrogen). The experiment started in August 2015 and was completed in May 2017. Braford growing heifers with initial age of 313 days and initial live weight of 136 kg were used. The experimental design was a randomized complete block with repeated measures in the time with two repetitions of area. The "Legumes" and "Nitrogen" reached body weight of 368.5 kg and 401.2 kg at the end of the end of the experiment, while "Control" and "Fertilization" presented 339.7 kg and 346.3 kg. The "Nitrogen" treatment maintained the highest animal load for a longer time, reaching its maximum load in the Summer of 2016/2017 with 854.7 kg ha-1. Due to the large amount of rainfall in this period, the "Control" treatment presented the highest animal load in the Autumn of 2017 with 435.3 kg ha-1. The "Legumes" and "Nitrogen" treatments did not present any financial return, with financial result, negative NM and RR. The "Fertilization" treatment presented a positive financial result, however with negative NM and RR. The intensification strategies used, increase the productivity of the system, but they do not present return on the investment, according to the used indicators, in the evaluated period.