Protein and carbohydrate fractionation of Urochloa spp. and Megathyrsus maximus forages after intercropping with soybean in an integrated crop-livestock system

Abstract

ABSTRACT The objective was to evaluate the protein and carbohydrate fractionation of forage plants of the Urochloa spp. and Megathyrsus maximus after intercropping with soybean in crop-livestock integration, in the off-season. The experimental design used was entirely randomised, with four repetitions, in a 4 × 5 factorial scheme. The treatments consisted of four forages: Xaraes palisadegrass (Urochloa brizantha cv. Xaraés), Ruziziensis grass (Urochloa ruziziensis), Mombaça guinea grass (Megathyrsus maximus cv. Mombaça), Tamani guinea grass (Megathyrsus maximus cv. BRS Tamani) and five grazing cycles (each grazing cycle was carried out every 28 days). Forage samples and protein and carbohydrate fractionation were obtained using destructive methods. The results showed that Tamani guinea grass and Xaraes palisadegrass presented higher fractions A of protein and carbohydrates and lower fraction C, being more suitable for integrated systems during the offseason. For all forages, there was a reduction in the protein and carbohydrate A fractions and an increase in the C fraction as grazing cycles advanced. Tamani guinea grass and Xaraes palisadegrass showed the best potential to be used for grazing in the off-season, by being planted as a replacement for soybean, and can be an alternative of quality food to be fed during the dry season.