02448naa a2200265 a 450000100080000000500110000800800410001910000160006024501420007626000090021852016230022765000250185065000120187565000120188765000250189965000250192465000270194965000260197665000110200270000200201370000210203370000220205470000180207677300880209413242422020-04-15       2001    bl uuuu     u00u1 u    #d1 aHERRERO, M.  aMeasurements of physical strengh and their relationship to the chemical composition of four species of Brachiaria.h[electronic resource]  c2001  aShear strength and grinding resistance of leaves of four species of Brachiaria collected a 4 and 6 weeks of re-growth wre determined using modifications of technique described in the literature. Physical attributes of strength were correlated with analyses of plant cell wall constituents and in vitro digestibility (IVDMD). Methodologies were compared to determine which was best able to describe the physical strength of the samples. Both the grinding resistance and the shear strength tchnique were able to detect differences between Brachiaria species and ages of re-growth. However, the shear strength technique was more sensitive for identifying physical strength differences at the species level. Both technique identified the same species (Brachiaria ruziziensis as the softest, but subsequent ranking of species by the shear strength technique depended on the leaf morphological characteristic used to express the results. Shear strength measurements were correlated to the cell wall components and IVDMD of the samples. The highest correlations were obtained for acid detergent fibre (ADF), cellulose and lignin with shear strength measurements expressed per unit of leaf width (kg/cm), per unit of linear density (kg/g cm) and for the raw shear strength data (kg). Grinding resistance was not correlated to the chemical composition and IVDMD of the samples.Preferential use of the shear strength technique is suggested since it provides a sensitive measure of the physical strength of forage leaf tissue and is a suitabel indicator for identifying nutrititive quality differences between Brachiaria species.  achemical composition  acutting  amilling  aBrachiaria Brizantha  aBrachiaria Decumbens  aBrachiaria Ruziziensis  aComposição Química  aMoagem1 aVALLE, C. B. do1 aHUGHES, N. R. G.1 aSABATEL, V. de O.1 aJESSOP, N. S.  tAnimal Feed Science and Technology, Amsterdamgv. 92, n. 3/4, p.149-158, Aug. 2001.