Herbage Responses and Grazing Performance of Mature Horses in Warm-Season Perennial Grass–Legume Mixed Pastures

• Published in: Grasses
• Main Authors: Ana Caroline Cerqueira de Melo Vasco, Erick R. da Silva Santos, Jose C. Batista Dubeux Junior, Lynn E. Sollenberger, Marcelo O. Wallau, Helio Lauro Soares Vasco Neto, Jill M. Lance, Lori K. Warren, Carissa L. Wickens
• Format: Article
• Language: English
• Published: MDPI AG 2025-04-01
• Subjects: bahiagrass; bodyweight; botanical composition; digestibility; fertilizer; herbage mass
• Online Access: https://www.mdpi.com/2813-3463/4/2/15

The pasture–animal interface of warm-season perennial grass–legume mixed pastures has never been investigated in forage-based equine systems. Therefore, this 2-year study investigated the herbage and animal responses under 84-day continuous stocking in mixed pastures of rhizoma peanut (RP, <i>Arachis glabrata</i> Benth) and bahiagrass (BG, <i>Paspalum notatum</i> Flüggé) with 30 kg nitrogen (N) ha⁻¹ (BG-RP) compared to BG pastures fertilized with 120 kg N ha⁻¹ (BG-N₁₂₀) and no N (BG-N₀). Measurements were taken every 14 days, except for intake and in vivo digestibility, which were measured every 28 days. BG-N₁₂₀ had the highest stocking rate (<i>p</i> = 0.01; 3.7 AU ha⁻¹) in 2019, while BG-N₀ had the lowest (<i>p</i> = 0.01; 2.6 AU ha⁻¹) in 2020. Crude protein and digestible energy were greatest (<i>p</i> < 0.05) for BG-N₁₂₀ and BG-RP in some of the evaluation days in 2019 but similar across pastures in 2020. Crude protein digestibility was greatest (<i>p</i> < 0.05) for BG-RP in the late season. Intake was less (<i>p</i> = 0.03) for horses grazing BG-RP (3.2%BW) compared to BG-N₀ (5.0%BW). Nonetheless, no differences (<i>p</i> > 0.05) were observed among pastures for body measurements. The results indicate that BG-RP pastures can improve forage nutritive value and maintain horse body condition while maintaining similar stocking rate to monoculture bahiagrass with high N fertilizer rates.