Tree legume enhances livestock performance in a silvopasture system

Abstract

AbstractSilvopastoral systems (SPSs) can increase overall productivity and long‐term income due to the simultaneous production of trees, forage, and livestock. This 2‐yr study evaluated animal performance and herbage responses in C4–grass monoculture or in SPS in the subhumid tropical region of Brazil. The experimental design was a randomized complete block with three replications. Treatments were: Urochloa decumbens (Stapf.) R. Webster (Signalgrass) + Mimosa caesalpiniifolia Benth (SPS–mimosa), Signalgrass + Gliricidia sepium (Jacq.) Kunth ex Walp (SPS–gliricidia), and signalgrass monoculture (SM). Response variables included herbage and livestock responses. Cattle were managed under continuous stocking with variable stocking rate. There was a treatment × month interaction for herbage mass. Green herbage accumulation rate ranged from 20 to 80 kg dry matter ha−1 d−1 across months, with SPS–mimosa presenting lower rates. Average daily gain was greater in SPS–gliricidia, followed by SM and SPS–mimosa (0.77, 0.56, and 0.23 kg d−1, respectively), varying across months. Stocking rate ranged from 0.86 to 1.6 AU ha−1. Total gain per area during the experimental period was greater for SPS–gliricidia (423 kg body weight [BW] ha−1), followed by signalgrass in monoculture (347 kg BW ha−1) and SPS–mimosa (50 kg BW ha−1). Silvopasture systems using signalgrass and gliricidia enhanced livestock gains compared with signalgrass in monoculture, and mimosa trees outcompeted signalgrass, reducing livestock gains. Silvopasture systems with tree legumes have the potential to provide numerous ecosystem services and to reduce the C footprint of livestock systems in the tropics; however, the choice of tree species is key and is determined by which ecosystem service is prioritized.