Artigo
Produção de forragem e composição estrutural de pastos de Brachiaria brizantha cv. Xaraés manejados em diferentes alturas de pastejo
Forage production and structural composition of pastures of Xaraes grass managed in different grazing heights
Registro en:
Semina-ciencias Agrarias. Londrina: Univ Estadual Londrina, v. 34, n. 6, p. 4145-4155, 2013.
1676-546X
10.5433/1679-0359.2013v34n6Supl2p4145
WOS:000340333600044
WOS000340333600044.pdf
Autor
Castro, Leticia Maria
Alves de Freitas Barbosa, Marco Aurelio
Barbero, Rondineli Pavezzi [UNESP]
Brito, Vinicius Campachi
Saad, Rafael Mantegazza
Azambuja Ribeiro, Edson Luis de
Mizubuti, Ivone Yurika
Bridi, Ana Maria
Resumen
The objective of this study was to analyze the production of dry mass, forage accumulation rate and the structural composition of Brachiaria brizantha cv. Xaraes pastures, managed under different grazing heights in continuous stocking. The experimental area was 12 hectares, divided in paddocks of one hectare each. The treatments were 15, 30, 45 and 60 cm of defoliation heights. Nellore steers were used to reach the desired heights. Every 28 days four cut samples and eight visual samples were collected for comparative performance in the experimental plots. Two grazing exclusion cages were used per treatment to estimate accumulation rates kg.ha(-1) DM. The cut material was taken to the laboratory for separation of the botanical components (green leaf, stem and senescent material), weighing and determination of dry matter. The experimental design was the completely randomized with three replicates. There were treatments effects at all seasons for the production of total mass, except in the spring. In summer and spring seasons it was observed the highest values for leaf blades (1.100 kg DM.ha(-1)). In the winter, the highest values of senescent material was observed, as expected. The average accumulation showed no significant difference among the treatments, except for stem and total mass in the summer and stem in the fall. The tillers were heavier and higher values for number of green leaves per tiller occurred in the fall, but for senescent leaves per tiller ocurred in the winter. Swards grazed at heights between 45 and 60 cm of defoliation, had good production of forage mass and leaf constituent. Univ Estadual Londrina, Londrina, PR, Brazil Univ Estadual Londrina, Dept Zootecnia, Londrina, PR, Brazil UNESP, Fac Ciencias Agr & Vet, Programa Posgrad Zootecnia, Jaboticabal, SP, Brazil Univ Estadual Londrina, Programa Posgrad Ciencia Anim, Londrina, PR, Brazil Prod CNPq, Londrina, PR, Brazil UNESP, Fac Ciencias Agr & Vet, Programa Posgrad Zootecnia, Jaboticabal, SP, Brazil