Optimization of tropical pastures for sustainable beef cattle finishing: fertilization or intercropping of grasses and legumes

Abstract

Pasture-based beef cattle production is essential to ensuring food security for the world's growing population. Sustainable intensification promotes more efficient land use, reducing the need for new production areas. This study evaluated the productive efficiency of tropical forage-based systems as viable strategies for the sustainable intensification of pasture-finished beef cattle production. The experiment was conducted from August 2021 to August 2022 at Embrapa Southeast Livestock, in São Carlos, SP, Brazil. A total of 27 animals (27 ± 1 months old; 355.2 ± 6.8 kg) were used. Three treatments were evaluated with three replications each: 1) degraded pasture of Urochloa  decumbens cv. Basilisk (DEG); 2) dryland pasture composed of U. decumbens cv. Basilisk and U. brizantha cv. Marandu, recovered with 200 kg.N-urea.ha^-1.year^-1 in the rainy season (REC); 3) dryland pasture with U. decumbens cv. Basilisk and U. brizantha cv. Marandu intercropped with Cajanus cajan cv. BRS Mandarim (MIX). Animals were allocated to nine paddocks (1.25 ha each), with three paddocks per treatment. Stocking rates were adjusted by the "put-and-take" technique, and the animals were weighed every 28 days. Performance data were submitted to ANOVA, the means were compared using the Fisher test (5%) in SAS^® (PROC MIXED). Final body weights were highest in MIX (575.2ᵃ kg), followed by REC (550.8ᵃ kg), and lowest in DEG (510.5ᵇ kg). The stocking rates (AU = 450 kg body weight) were highest for MIX and REC (3.43ᵃ and 3.24ᵃ AU/ha, respectively), and DEG was the lowest (2.25ᵇ AU/ha). These results demonstrate that MIX and REC significantly improved animal performance and land use efficiency compared to the DEG. Among them, MIX showed the highest final body weight and stocking rate, highlighting the potential of legume-grass intercropping as a strategy for the sustainable intensification of beef cattle production on pasture.