Estimation of dry matter intake by lambs managed on different leaves allowance of Brachiaria-grass using internal and external markers.

It aimed to estimate the forage intake by lambs managed in different leaf allowances on Brachiaria-grass using internal and external markers. Forty-eight Texel lambs with 17.52 ± 3.48 kg were evaluated which were 12 testers and 36 regulators. The lambs were kept in twelve paddocks, subdivided into four treatments based on green leaf allowance (60, 75, 90, and 105 g/kg of BW). The experimental design was completely randomised. To estimate dry matter intake (DMI), the following markers were used: indigestible dry matter (iDM); indigestible neutral detergent fibre (iNDF); indigestible acid detergent fibre (iADF); lignin in indigestible acid detergent (iADL) and titanium dioxide (TiO2). Comparisons between intake markers were made using Chromic Oxide (Cr2O3) as a control marker. The leaves allowance tested did not alter the voluntary intake by lambs kept in Brachiaria-grass pasture. Comparison between the control intake marker (Cr2O3) and the other markers by Dunnett's test showed that, regardless of green leaf allowance, the Cr2O3, TiO2 and iADL markers provided similar estimates of DMI, but with lower values than the other markers. External marker TiO2 and the internal iADL were demonstrated to be more suitable for estimating the dry matter intake in grazing lambs regardless of the leaf allowance. [ABSTRACT FROM AUTHOR]