title: Sward structure and nutritive value of Alexandergrass fertilized with nitrogen.
abstract: This experiment evaluated forage production, sward structure, stocking rate, weight gain per area and nutritive value of forage as grazed by beef heifers on Alexandergrass (Urochloa plantaginea (Link) Hitch) pasture fertilized with nitrogen (N): 0; 100; 200 or 300 kg of N/ha. The experiment was a completely randomized design following a repeated measurement arrangement. The experimental animals were Angus heifers with initial age and weight of 15 months and 241.5±5 kg, respectively. The grazing method was continuous, with put-and-take stocking. N utilization, regardless of the level, increase by 25% the daily forage accumulation rate and the weight gain per area by 23%. The level of 97.2 kg N/ha leads to a higher leaf blade mass and increases by 20% the leaf:stem ratio. Alterations in sward structure changes the nutritive value of forage as grazed. The utilization of 112.7 kg of N/ha allows the highest stocking rate (2049.8 kg of BW/ha), equivalent to 7.5 heifers per hectare.
authors.affiliation: Departamento de Zootecnia, Universidade Federal de Santa Maria, Santa Maria, RS, Brasil.
authors.forename: Paulo R
authors.initials: PR
authors.lastname: Salvador
authors.affiliation: Departamento de Zootecnia, Universidade Federal de Santa Maria, Santa Maria, RS, Brasil.
authors.forename: Luciana
authors.initials: L
authors.lastname: Pötter
authors.affiliation: Departamento de Zootecnia, Universidade Federal de Santa Maria, Santa Maria, RS, Brasil.
authors.forename: Marta G
authors.initials: MG
authors.lastname: Rocha
authors.affiliation: Departamento de Zootecnia, Universidade Federal de Santa Maria, Santa Maria, RS, Brasil.
authors.forename: Anelise P
authors.initials: AP
authors.lastname: Hundertmarck
authors.affiliation: Departamento de Zootecnia, Universidade Federal de Santa Maria, Santa Maria, RS, Brasil.
authors.forename: Maria José O
authors.initials: MJ
authors.lastname: Sichonany
authors.affiliation: Departamento de Zootecnia, Universidade Federal de Santa Maria, Santa Maria, RS, Brasil.
authors.forename: Luiz G
authors.initials: LG
authors.lastname: Amaral Neto
authors.affiliation: Departamento de Zootecnia, Universidade Federal de Santa Maria, Santa Maria, RS, Brasil.
authors.forename: Mateus
authors.initials: M
authors.lastname: Negrini
authors.affiliation: Departamento de Zootecnia, Universidade Federal de Santa Maria, Santa Maria, RS, Brasil.
authors.forename: Paulo H
authors.initials: PH
authors.lastname: Moterle
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000822:Animal Husbandry; D000818:Animals; D002417:Cattle; D005260:Female; D009584:Nitrogen / Q000494:pharmacology*; D009753:Nutritive Value; D006109:Poaceae / Q000737:chemistry / Q000187:drug effects / Q000254:growth & development*; D012621:Seasons; D015430:Weight Gain
chemical_list: D009584:Nitrogen