113-9 Reducing N Inputs in Grazing Systems By Introducing Rhizoma Peanut.

See more from this Division: C06 Forage and Grazinglands
See more from this Session: Forage and Grazinglands Oral I

Monday, November 7, 2016: 3:45 PM
Phoenix Convention Center North, Room 225 A

Liza Garcia1, Jose Carlos Batista Dubeux Jr.2, Lynn E. Sollenberger3, Joao M.B. Vendramini4, Nicolas DiLorenzo2, Erick Rodrigo da Silva Santos2, David Jaramillo5 and Martin Ruiz-Moreno6, (1)Agronomy, University of Florida, Marianna, FL
(2)North Florida Research and Education Center, University of Florida, Marianna, FL
(3)Agronomy Department, University of Florida, Gainesville, FL
(4)3401 Experiment Station, University of Florida, Ona, FL
(5)University of Florida North Florida Research & Extension Center, Marianna, FL
(6)NFREC, University of Florida, Marianna, FL
Abstract:
Nitrogen fertilizer increases carbon footprint of livestock systems. Forage legumes are a possible alternative to replace N fertilizers. Rhizoma peanut - RP (Arachis glabrata Benth.) is one of the few warm-season perennial legumes that have demonstrated persistence under a range of grazing conditions. This research evaluated the potential benefits of including RP in livestock-forage systems in North Florida. The experiment was conducted from July to October of 2015 and will be repeated in 2016. Treatments consisted of three livestock production systems as follows: 1) Argentine bahiagrass fertilized with 113 kg of N ha-1 (BHF); 2) unfertilized Argentine bahiagrass (BH); 3) Strip-planted Ecoturf rhizoma peanut mixed with Argentine bahiagrass (BHR). Treatments were replicated in three blocks in a randomized complete block design. Pastures were continuously grazed using a variable stocking rate.  No treatment × evaluation period (P = 0.52), or treatment effect (P = 0.06) were found for herbage allowance. Treatment x evaluation period effects were observed for ADG (P = 0.05) and herbage mass (P = 0.02). Stocking rate and gain per area did not differ among treatments (P > 0.05). Season ADG was 0.33, 0.22, and 0.16 kg head-1 d-1 for BHR, BHF, and BH, respectively. Fecal δ13C indicated that an average of 72% of C found in the feces of cattle grazing RP paddocks were from C3 species. Fecal N concentration was greater from samples collected from cattle grazing RP (22.8 g N kg-1) than cattle grazing BH (17.7 g N kg-1). Greater proportion of C3 species in the diet of cattle grazing RP was also reflected in plasma and red blood cells using δ13C. Including RP strip-planted into bahiagrass pastures allowed reduction of N fertilization and maintained livestock gain per area when compared to systems without legumes, whether fertilized or not with nitrogen.

Keywords: Rhizoma peanut, N fertilizer, beef cattle.

See more from this Division: C06 Forage and Grazinglands
See more from this Session: Forage and Grazinglands Oral I

<< Previous Abstract | Next Abstract