Chemical Composition,in VitroDigestibility and Gas Production ofBrachiariaManaged Under Different Forage Allowances

Abstract

The objective of this study was to evaluate the chemical composition, in vitro digestibility, gas production and fermentation kinetics of three Brachiaria cultivars: Brachiaria brizantha cv. Marandu, Brachiaria brizantha cv. Xaraes, and hybrid Brachiaria cv. Mulato, subjected to different levels of forage allowance (4, 7, 10 and 13% of the animal body weight), under rotational grazing cycles. Cultivar Xaraes presented higher contents of neutral detergent fibre, neutral detergent fibre corrected for ash and protein, acid detergent fibre and lignin, and lower production of gases in 96 h in the component leaf blade. There was a decrease of non-fibrous carbohydrates and fraction B2 and an increase in the fraction C of the carbohydrates in the components stem and leaf blade over the grazing cycles in all the cultivars. Cultivar Marandu presented higher digestibility values (in vitro organic matter digestibility and in vitro dry matter digestibility) in the components stem and leaf blade. Cultivar Mulato demanded a shorter time of colonisation, according to the calculations of fermentation kinetics. Regardless of the level of forage allowance and of the grazing cycles, the three Brachiaria cultivars were characterised by great fermentation quality due to the relations of the gas production potential and the gas production after 48 and 96 h.

Diurnal vertical and seasonal changes in non-structural carbohydrates in Marandu palisade grass

“…The greater IVDDM in leaf blade than pseudostem observed in Experiment 2 of the current study was demonstrated earlier in Marandu palisade grass by Ribeiro et al (2014). This reflected greater IVDDM in the upper than intermediate canopy layer observed in Experiment 1.…”

Herbage allowance effects on the characteristics of Brachiaria brizantha cv. Marandu pastures and the production and economic viability of Nellore heifersicas das pastagens de Brachiaria brizantha cv. Marandu e na produção e viabilidade econômica de novilhas Nelore

“…Marandu to accumulate more constituents in the cell wall during the water period, as the increase in herbage allowance was due to the increase in forage mass. Ribeiro et al (2014) found no significant differences in the chemical composition (CP, NDF, and ADF) or the DM digestibility, but the increase in allowance in their study was through area increase and not through herbage mass increase. For the 15 kg DM 100 -1 BW herbage allowance, the pasture showed a lower proportion of leaves and lower nutritional value (Table 1) because of higher NDF levels in leaves and stems that may have negatively influenced the DM digestibility.…”

Weed Interference in the Establishment of Urochloa ruziziensis

“…In this case, there are two periods before interference (PAI) for U. ruziziensis: one for biomass and another for methane production, the latter an indicator of quality, as several authors have reported a link between GHG production and forage quality (Johnson and Johnson,1995;Johnson and Ward, 1996;Haper et al, 1999;Ribeiro, 2014). Jakelaitis et al (2010) found a similar result, in which the period before interference for U. brizantha was nine days, with a biomass reduction of 40% if the control is not carried out at an appropriate time.…”

“…Dead material dry biomass (DMDB), total dry biomass (TDB), fresh leaf volumetric density (FLVD) obtained at 90 DAE as a function of weed coexistence periods. Barra do Garças, MT, 2016Ribeiro (2014) studied the total gases emission (in vitro) in leaves of the grasses U. brizantha cv. Marandu, U. brizantha cv.…”