Maintenance of mixed grass-legume pastures for stand longevity and improved animal utilization is a challenge in warm-season climates. The goal of this study was to assess grazing management on stand persistence, forage intake, and N balance of beef heifers grazing mixed pastures of Brachiaria brizantha and Arachis pintoi. A two-year experiment was carried out in Brazil, where four grazing management were assessed: rest period interrupted at 90%, 95%, and 100% of light interception (LI) and a fixed rest period of 42 days (90LI, 95LI, 100LI, and 42D, respectively). The LI were taken at 50 points at ground level and at five points above the canopy for each paddock using a canopy analyzer. For all treatments, the post-grazing stubble height was 15 cm. Botanical composition and canopy structure characteristics such as canopy height, forage mass, and vertical distribution of the morphological composition were evaluated pre-and post-grazing. Forage chemical composition, intake, and microbial synthesis were also determined. A randomized complete block design was used, considering the season of the year as a repeated measure over time. Grazing management and season were considered fixed, while block and year were considered random effects. In the summer, legume mass accounted for 19% of the canopy at 100LI, which was less than other treatments (a mean of 30%). The 100LI treatment had a greater grass stem mass compared with other treatments. In terms of vertical distribution for 100LI, 38.6% of the stem mass was above the stubble height, greater than the 5.7% for other treatments. The canopy structure limited neutral detergent fiber intake (P = 0.007) at 100LI (1.02% of BW/d), whereas 42D, 90LI, and 95LI treatments had NDF intake close to 1.2% of BW/d. The intake of digestible organic matter (OM; P = 0.007) and the ratio of crude protein/digestible OM (P < 0.001) were less at 100LI in relation to the other treatments. The production of microbial N (P < 0.001) and efficiency of microbial synthesis (P = 0.023) were greater at 95LI and 90LI, followed by 42D and less at 100LI. Overall, the range from 90 to 95% of LI is the recommendation to interrupt the rest period, since this strategy enhanced community stability, forage intake, and nutritional value of the diet. Under on-farm conditions, brachiaria grass and forage peanut pastures should be managed at a range height of 24 to 30 cm.

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Legumes can contribute significantly to nitrogen (N) input in grazing systems. Grazing management is a critical factor affecting N cycling in mixed pastures, altering the legume N input as a result. This study assessed how defoliation frequency affects N cycling in rotationally stocked palisadegrass (Brachiaria brizantha) and forage peanut (Arachis pintoi) pastures. Treatments included four grazing management strategies, defined by the rest period interruption when the canopy reached 90 (90LI), 95 (95LI), and 100% (100LI) of photosynthetically active radiation interception (LI), and a fixed rest period of 42 d (42D). A 2‐yr experimental period was adopted. Existing litter was greater at 100LI (2208 vs. 1964 kg ha−1; average of 42D, 90LI, and 95LI, respectively). Greater defoliation frequency (42D and 90LI) resulted in increase of litter legume proportion, resulting in greater decomposition rate, lower litter half‐life (p < .001, and p = .015, respectively), and greater N cycling (91 vs. 64 kg ha−1 season−1). Less frequent defoliation (100LI) resulted in reduced total forage intake, proportion of legume intake, and lower N intake compared with other treatments (p = .007, p = .081, and p < .001, respectively). Greater defoliation frequency increased N cycling via litter, but did not affect excretion due to compensation with stocking rate. Defoliation frequency between 90 and 95% LI optimizes N cycling in palisadegrass‐forage peanut mixed pastures.