THE IN VITRO DIGESTIBILITY OF WHOLE GRASSES AND THEIR PARTS AT PROGRESSIVE STAGES OF MATURITY

Abstract

The in vitro dry matter digestibility (IVD) of timothy, orchard, brome, reed canary, tall fescue and mountain rye grasses decreased at the rate of approximately 0.5 per cent per day throughout the growing season. The most rapid decline in IVD began with head emergence. The earliest maturing grasses tended to be higher in IVD than the other grasses at the flowering stage. The decline in IVD as the season progressed was observed in all portions of the plant, the rate of decline for the heads and stems being greater than for the leaves. The upper segments of the stems tended to have a lower IVD than the basal segments.

Contribution of Stems and Leaves to the Composition and Nutrient Content of Irrigated Bromegrass at Different Stages of Development

“…Thereafter, the rate of yield increase was less and total yield did not exceed 9,000 kglha (Fig. 1) (Pritchard et al 1963) (Fig. 3).…”

Maturation effects on forage quality of Kentucky bluegrass

“…Mots clés: Poa pratensis L., qualité fourragère, graminée vivace, feuille, tige Herbage quality of cool-season grasses declines with advancing maturation. Herbage digestibility and CP concentration decrease, whereas fiber and lignin concentrations increase with maturation (Pritchard et al 1963;Mowat et al 1965). The decline in whole herbage quality of smooth bromegrass (Bromus inermis Leyss) with maturation was attributed to a decrease in the leaf/stem mass ratio as well as to changes in the quality of leaf and stem fractions.…”

“…The decline in whole herbage quality of smooth bromegrass (Bromus inermis Leyss) with maturation was attributed to a decrease in the leaf/stem mass ratio as well as to changes in the quality of leaf and stem fractions. Leaves and stems of tall growing grasses may have similar digestibility when vegetative, but by heading, stems typically have lower digestibility and CP concentration and higher lignin and fiber concentration than leaves (Pritchard et al 1963;Smith 1973;Sanderson and Wedin 1989). Species differences in leaf and stem quality at post-heading stages result, in part, from varying rates of decline in quality of each fraction (Buxton and Marten 1989).…”

Differences in Feeding and Management Associated With Milk Yields in Ontario Dairy Herds

“…Information obtained from questionnaires and herd reports (Miller 1969 (Tilley and Terry 1963, as modified by Pritchard et al 1963). Energy values for feeds were determined using equations based on acid detergent fiber content (Moe and Tynell 1976;Adams 1975 : .E ,-.46e€g"n t-.2;--E F"i : .…”