Voluntary intake of three cultivars of Panicum maximum under grazing

Revista Brasileira de Zootecnia

Euclides, Valéria Pacheco Batista¹  Macedo, Manuel Claudio Motta¹  Thiago, Luiz Roberto Lopes de S.¹  Oliveira, Marcelo Paschoal de¹ 

[1] EMBRAPA

关键词: Brazilian savannas;    guineagrass;    forage availability;    daily weight gain;    grazing time;    nutritive value     Introdução O consumo de nutrientes digestíveis é o produto da quantidade de forragem consumida pela digestibilidade dos nutrientes nessa forragem;   

DOI  :  10.1590/S1516-35981999000600002

学科分类：兽医学

来源: Universidade Federal de Vicosa

【 摘 要 】

The objectives of this work were to estimate the dry matter intake by animals grazing three cultivars of Panicum maximum, and to relate it to live weight gain, grazing time (GT) and some structural and chemical characteristics of the pastures. The experimental design was the randomized block with three treatments and three replicates. The dry matter voluntary intake (DMVI) was estimated in four periods (May, September, November and February). Fecal output was measured using chromic oxide as an external marker. In situ dry matter digestibility was estimated from extrusa obtained by esophageal fistulated animals, and grazing time was registered by vibracorders. Also, forage availability and plant components were estimated. Greater differences in live weight gains were observed, for the animals grazing Tanzânia followed by those grazing Colonião and Tobiatã, although DMVI among cultivars were similar. There were also smaller differences among cultivars for the GT for animals grazing Tobiatã as compared to those grazing the other two cultivars. The increase in the GT observed during the dry season was not enough to avoid a decrease in the forage intake, during the same period. The VIDM was highly correlated (r2 = 0.77) with daily live weight gains. Structural characteristics of the forages, leaf availability and green matter:dead matter ratio, affected more the VIDM, daily weight gain and GT than their nutritive value.

【 授权许可】

CC BY-NC