Ps. Mir et al., PREDICTION OF NUTRIENT COMPOSITION AND IN-VITRO DRY-MATTER DIGESTIBILITY FROM PHYSICAL CHARACTERISTICS OF FORAGES, Animal feed science and technology, 55(3-4), 1995, pp. 275-285
In order to develop equations to estimate nutrient composition and in
vitro dry matter digestibility (IVDMD) of forages from physical charac
teristics, grasses (timothy, reed canary grass and brome grass) and le
gumes (alfalfa and red clover) were harvested at different stages of m
aturity and analyzed for content of nutrient components, and the IVDMD
and physical characteristics were determined. Physical characteristic
s were used to develop multiple regression equations to estimate conte
nt of nutrient components (crude protein, acid detergent fibre, neutra
l detergent fibre, acid detergent insoluble nitrogen and lignin) and I
VDMD for each forage. The equations for the grasses included only grin
ding resistance either in linear or square terms, The regression coeff
icient (r(2) or R(2)) (P < 0.05) of the equations ranged from 0.5 to 0
.94 for timothy, 0.82 to 0.93 for reed canary grass, 0.4 to 0.96 for b
rome, 0.65 to 0.96 for alfalfa and from 0.71 to 0.97 for red clover. T
he coefficients of regression (r(2)) between determined and estimated
values for protein and IVDMD of timothy and brome grass were 0.76 and
0.59, and 0.76 and 0.66, respectively, Thus crude protein content and
IVDMD of timothy and brome grass can be estimated from grinding resist
ance of the forages from the respective equations.