The effect of temperature on quality characteristics in timothy (Phleum pratense L.) genotypes

1993 ◽  
Vol 73 (4) ◽  
pp. 1017-1026 ◽  
Author(s):  
N. Ames ◽  
A. R. McElroy ◽  
J. Erfle
Keyword(s):  
Dry Matter ◽  
Nutritive Value ◽  
Genetic Factors ◽  
Lignin Content ◽  
Rumen Fluid ◽  
Phleum Pratense ◽  
Effect Of Temperature ◽  
Genotypic Differences ◽  
Genetic Traits ◽  
Phleum Pratense L

Improving the nutritive value of timothy (Phleum pratense L.) through breeding is dependent on selecting for genetic traits which directly contribute to ruminant digestibility. The identification of these traits is the goal of many forage researchers. The objectives of this research were to evaluate the leaf and stem digestibility of six timothy genotypes under different temperature conditions using two methods of estimating digestibility. Correlations between leaf and stem digestibility were not significant, suggesting that separation of these components is nessessary to clearly evaluate genotypic differences. Temperature had an important effect on digestibility, particularly for the stem fraction. Isolating leaf from stem and evaluating genotypes individually across temperatures may permit the identification of more simple genetic factors which control digestibility in timothy. Genotypic differences were observed at all temperatures. The rumen fluid digestion resulted in a much greater range within and among genotypes for both stem and leaf fractions. Genotypes tended to follow the same trends with respect to temperature using both techniques suggesting that only a portion of the dry matter digested by rumen fluid is available to the cellulases used in these experiments. Lignin content was measured for two of the most variable genotypes and the results showed that while levels increased with higher growth temperature, differences between genotypes are more pronounced at 10 °C for both leaf and stem. Key words: Digestibility, forage quality, lignin, temperature, timothy, Phleum pratense L.

THE COMPARATIVE NUTRITIVE VALUE OF SPARTINA PECTINATA AND TIMOTHY AT SEVERAL STAGES OF GROWTH

1965 ◽  
Vol 45 (3) ◽  
pp. 157-163 ◽  
Author(s):  
J. W. G. Nicholson ◽  
J. E. Langille
Keyword(s):  
Acetic Acid ◽  
Dry Matter ◽  
Nutritive Value ◽  
Rumen Fluid ◽  
Energy Requirement ◽  
Late Summer ◽  
Phleum Pratense ◽  
Spartina Pectinata ◽  
Stages Of Growth ◽  
Stage Of Development

Spartina pectináta (Link) was harvested at four stages of growth (leaf, boot, head, and seed) from an unfertilized area of dikeland and at the final three dates following a late spring application of nitrogen fertilizer. This was compared with timothy (Phleum praténse L.) grown on unfertilized dikeland and harvested on five dates selected to include a similar range of physiological development.The digestibility of dry matter, organic matter and nitrogen, the dry matter consumption by sheep, and the nitrogen content declined as the forages matured. The rate of decline in digestibility of dry matter was greater for the timothy, but there was a maximum difference between species of only 3.5 percentage units.The timothy was consumed in greater amounts by sheep than spartina of similar digestibility. Consumption of the two species did not differ significantly at the seed stage of development, but at immature stages more timothy was consumed.All except the earliest cutting of spartina gave a significantly higher proportion of acetic acid and lower proportion of propionic acid in rumen fluid than did feeding timothy. Advancing maturity had no effect on the proportions of VFA from timothy; with spartina there was an increase in acetic acid and a decrease in butyric acid.It was concluded that spartina harvested at the conventional time in late summer is low in digestibility and is not consumed in sufficient quantity to meet the energy requirement of sheep.

Leaf and stem nutritive value of timothy cultivars differing in maturity

1997 ◽  
Vol 77 (2) ◽  
pp. 237-249 ◽  
Author(s):  
G. Bélanger ◽  
R. E. McQueen
Keyword(s):  
Cell Wall ◽  
Dry Matter ◽  
Nutritive Value ◽  
Weight Ratio ◽  
Phleum Pratense ◽  
Cultivar Differences ◽  
Early Maturing ◽  
True Digestibility ◽  
Phleum Pratense L

The nutritive value of herbage is a function of the nutritive value of its component leaves and stems and their proportion in the herbage. A previous study indicated that the proportion of leaves in the herbage did not explain entirely the differences in in vitro true digestibility and NDF concentrations between early and late-maturing timothy (Phleum pratense L.) cultivars. It was therefore hypothesized that the leaves and stems of early and late-maturing cultivars differ in nutritive value. The evolution of leaf and stem nutritive value of field-grown timothy cultivars differing in maturity, and the relationships between parameters of leaf and stem nutritive value, and the leaf to weight ratio (LWR) were studied during primary growth in two experiments. On a given date, stems of early-maturing cultivars had in vitro true digestibilities of dry matter and cell wall up to 61 g kg−1 DM and 71 g kg−1 DM lower that those of late-maturing cultivars, respectively. The NDF concentration of stems of early-maturing cultivars was up to 32 g kg−1 DM greater than that of late-maturing cultivars. There were no cultivar differences in leaf in vitro true digestibilities of dry matter and cell wall, and NDF concentration on a given date. At a given LWR, however, the leaves and stems of early-maturing cultivars had greater in vitro true digestibilities of dry matter and cell wall, and a lower NDF concentration than those of late-maturing cultivars. Our results indicate that differences in herbage nutritive value at a given stage of maturity between early- and late-maturing timothy cultivars is explained by a greater nutritive value of leaves and stems of the early-maturing cultivars. Key words: Phleum pratense L., timothy, cultivar, digestibility, cell wall, leaf, stem

Delayed harvest affects mineral and NDF concentrations, and digestibility of timothy

2008 ◽  
Vol 88 (2) ◽  
pp. 325-329 ◽  
Author(s):  
S. Pelletier ◽  
G. F. Tremblay ◽  
G. Bélanger ◽  
P. Seguin ◽  
R. Drapeau ◽  
...  
Keyword(s):  
Key Words ◽  
Dry Matter ◽  
Metabolic Disorders ◽  
Nutritive Value ◽  
Phleum Pratense ◽  
Neutral Detergent Fiber ◽  
Fiber Concentration ◽  
Harvest Delay ◽  
Phleum Pratense L

A 1-wk delay after late heading in the harvest of timothy spring growth reduced dietary cation-anion difference (-17%), in vitro digestibilities of dry matter (-7%) and neutral detergent fiber (-10%), and increased neutral detergent fiber concentration (+5%). In summer regrowth, the harvest delay tended to have similar effects, but variations (1-6%) were smaller. Key words: Nutritive value, stages of development, Phleum pratense L., metabolic disorders

scholarly journals The quality of the forage eaten by Norwegian reindeer on South Georgia in summer

Rangifer ◽  
2000 ◽  
Vol 20 (2-3) ◽  
pp. 17 ◽  
Author(s):  
Svein D. Mathiesen ◽  
Tove H. Aagnes Utsi
Keyword(s):  
Crude Protein ◽  
Dry Matter ◽  
Plant Cell Wall ◽  
Lignin Content ◽  
Rumen Fluid ◽  
Phleum Pratense ◽  
Water Soluble ◽  
Soluble Carbohydrates ◽  
High Quality ◽  
South Georgia

The chemical composition and digestibility of plants selected by Norwegian reindeer (Rangifer t. tarandus) on the sub-Antarctic island of South Georgia (SG) were investigated in the austral summer and compared with two qualities of standard grasses of Phleum pratense of European origin. Paridiochola flabellata, Poa pratense, Poa annua, Deschampsia antarctka, and Phleum alpinum collected on SG contained 14.8, 17.6, 22.8, 16.1 and 10.1% respectively of crude protein of dry matter (DM). Aceana magellanica also collected on SG contained 19.8% of crude protein and 18.8% of water-soluble carbohydrates (WSC) of DM, while the tussock grass P. flabellata, contained as much as 29-3% of WSC of DM. Total plant cell-wall contents (CWC), including cellulose, hemi-cellulose and lignin in P. flabellata, P. pratense, P. annua and P. alpinum were 53.2, 49.6, 41.7 and 40.4% of DM respectively, while A. magellanica contained only 17.5% of DM CWC. The lignin concentrations of plants analysed varied between 1.2 and 3.2% of DM. Mean in vitro dry matter digestibility (IVDMD) of selected plants ranged from 70% in P. flabellata to 83% in P. alpinum after 48 h incubation in rumen fluid from these reindeer. In contrast, the IVDMD of the poor and high quality standard grass Phleum pratense were 54% and 73% of DM, respectively. The forage eaten by reindeer on SG in summer was of high quality, with low lignin content, moderate protein concentration and high degradability in rumen fluid.

EVALUATION OF TIMOTHY CULTIVARS FOR VOLUNTARY INTAKE AND NUTRIENT COMPONENTS

1988 ◽  
Vol 68 (4) ◽  
pp. 1121-1129 ◽  
Author(s):  
W. N. MASON ◽  
P. M. FLIPOT
Keyword(s):  
Key Words ◽  
Dry Matter ◽  
Phleum Pratense ◽  
Dry Matter Intake ◽  
Dry Matter Yield ◽  
Dry Matter Digestibility ◽  
Flower Stage ◽  
Voluntary Intake ◽  
Phleum Pratense L

Five timothy (Phleum pratense L.) cultivars, Clair, Champ, Milton, Climax and Bounty, were harvested at first flower stage during 2 consecutive years and in the regrowth for 1 yr. The forages were each offered as hay to 15 young rams to evaluate voluntary intake. Five animals were used to determine initial harvest dry matter digestibility. The cultivars varied significantly in voluntary intake at first flower stage. The highest intake (g kg−0.75 d−1) averaged for the years was obtained in the early cultivar Champ (65.9), which was 10% more than that of the medium-late cultivar Climax. The cultivars did not differ significantly in dry matter digestibility. In the regrowth, the relative intakes of the cultivars were essentially reversed from that of the initial harvest. The voluntary intake was substantially higher but the differences among forages were less marked. Climax regrowth voluntary intake was higher (P < 0.05) than all cultivars, except Bounty. A 15% range in digestible dry matter intake was present among cultivars. The ranking of the culivars for digestible dry matter was different than for dry matter yield. Key words: Timothy, Phleum pratense L., voluntary intake, dry matter digestibility

NUTRITIVE VALUE OF FORMALDEHYDE-TREATED RAPESEED MEAL FOR DAIRY CALVES

1972 ◽  
Vol 52 (2) ◽  
pp. 363-371 ◽  
Author(s):  
H. R. SHARMA ◽  
J. R. INGALLS ◽  
J. A. McKIRDY
Keyword(s):  
Dry Matter ◽  
Volatile Fatty Acids ◽  
Nutritive Value ◽  
Rumen Fluid ◽  
Protein Digestibility ◽  
Rapeseed Meal ◽  
Dairy Calves ◽  
Plasma Urea ◽  
Significant Difference ◽  
Daily Gain

Treatment of oilseed meals with formaldehyde (FA) and glutaraldehyde (GA) significantly (P < 0.01) reduced the solubility of protein in 0.02 N NaOH and the production of NH3 in the artificial rumen. Ten Holstein and Holstein × Brown Swiss calves of both sexes were fed two test rations containing either 26% untreated or formaldehyde-treated (5.6 g FA per 100 g protein) rapeseed meal (FA-treated RSM) for 14 weeks. Plasma urea nitrogen (N) and rumen NH3 levels were significantly (P < 0.01) lower in the FA-treated RSM calves compared with the control calves during the first 8 weeks of the growth trial. No significant difference (P > 0.05) in dry matter consumption, daily gain, or feed efficiency was observed. Total volatile fatty acids (VFA) (mmoles/100 ml) concentration was significantly higher (P < 0.05) in rumen fluid from the control calves compared with those receiving treated RSM. Molar percentages of the VFA’s were not significantly different (P > 0.05) between the two groups. In the N balance and digestibility trial, dry matter consumption did not differ significantly (P > 0.05); however, the FA-treated RSM resulted in decreased (P < 0.05) dry matter and crude protein digestibility. Calves receiving the treated RSM had reduced (P < 0.01) urinary N excretion; however, there was no significant effect (P > 0.05) on N consumption and retention.

Leaf and stem nutritive value of timothy grown with varying N nutrition in spring and summer

1999 ◽  
Vol 79 (2) ◽  
pp. 223-229 ◽  
Author(s):  
G. Bélanger ◽  
R. E. McQueen
Keyword(s):  
Cell Wall ◽  
Nutritive Value ◽  
Nitrogen Deficiency ◽  
Phleum Pratense ◽  
Shoot Biomass ◽  
Negative Effect ◽  
N Deficiency ◽  
Rate Of Decline ◽  
Phleum Pratense L

Nitrogen fertilization is known to have a limited effect on the digestibility of grasses. In a previous paper, however, we reported that N deficiency increased the proportion of leaves in the shoot biomass, and hence, indirectly increased the digestibility of timothy (Phleum pratense L). This was mitigated by the direct negative effect of N deficiency on the digestibility of leaves or stems or both early in the regrowth. The objective of this study was to determine the direct effect of N deficiency on three parameters of nutritive value of leaves and stems of timothy cv. Champ. The evolution of leaf and stem in vitro true digestibility (IVTD), in vitro cell wall digestibility (IVCWD), and neutral detergent fiber (NDF) concentration of field-grown timothy fertilized with four rates of N was studied during a spring and summer regrowth cycle by sampling at weekly intervals. The rate of decline in leaf nutritive value in spring was greater than that in summer, and was less than the rate of decline in stem nutritive value during spring. Nitrogen deficiency consistently increased the NDF concentration of leaves but had a lesser effect on the NDF concentration of stems. Nitrogen deficiency decreased leaf IVCWD when the leaf-to-weight ratio (LWR) was high early in the spring and summer regrowth cycles. At the end of regrowth when LWR values were low, leaf IVCWD was greatest when no N was applied. As a result, the negative effect of N deficiency on the leaf IVTD during the early part of the spring and summer regrowth cycles diminished as the regrowth cycles progressed. Nitrogen deficiency had a limited effect on stem IVCWD. We concluded that the direct negative effect of N deficiency on the digestibility of the timothy shoot biomass can be attributed primarily to its effect on the NDF concentration and cell wall digestibility of leaves. Key words: Phleum pratense L., grasses, digestibility, cell wall, nitrogen

EFFET DE L’APPLICATION D’AZOTE ET DU STADE DE CROISSANCE A LA RECOLTE SUR LA PERFORMANCE DE LA FLEOLE DES PRES (PHLEUM PRATENSE)

1977 ◽  
Vol 57 (3) ◽  
pp. 955-962 ◽  
Author(s):  
J. C. ST-PIERRE ◽  
G. PELLETIER
Keyword(s):  
Protein Content ◽  
Nitrogen Fertilization ◽  
Crude Protein ◽  
Dry Matter ◽  
Phleum Pratense ◽  
Dry Matter Yield ◽  
Stages Of Growth ◽  
Dry Matter Digestibility ◽  
Set Up ◽  
Phleum Pratense L

An experiment was set up to determine the effect of time and rate of nitrogen fertilization and stage of growth at first cut on yield and digestibility of dry matter and protein content of two timothy (Phleum pratense L.) cultivars, at each of two cuts, No difference in yield or chemical composition was found between cultivars. Highest yields and crude protein contents were measured at rates of nitrogen fertilizer of 112 and 224 kg/ha. Higher yield and protein content were obtained with NH4NO3 applied totally or in split applications in the spring than with urea in the fall. Dry matter digestibility (DDM) was not affected by nitrogen at rates of 56, 112 and 224 kg/ha. First cut was taken at two different stages of growth, and the second cut was taken on the same day in all the plots. At anthesis, yields were higher than at the head stage but DDM and protein content were lower. The opposite was found at the second cut. Except in 1973, total dry matter yield was not affected by the stage of growth at first cut.

The cellulose-lignin complex in forages and its relationship to forage nutritive value

1970 ◽  
Vol 74 (1) ◽  
pp. 23-36 ◽  
Author(s):  
D. W. Allinson ◽  
D. F. Osbourn
Keyword(s):  
Growth Phase ◽  
Dry Matter ◽  
Nutritive Value ◽  
Lignin Content ◽  
Italian Ryegrass ◽  
Difference Spectra ◽  
Dry Matter Digestibility ◽  
Lignin Fraction ◽  
Acid Detergent Fibre ◽  
Cellulose Digestibility

SUMMARYThe relationships between the cellulose-lignin complex, voluntary consumption and dry-matter digestibility were examined using forages of two varieties of Italian ryegrass and two legumes, lucerne and sainfoin. These forages had previously been shown to exhibit different intake-digestibility relationships. The cellulose, acid detergent lignin and acid detergent fibre contents of these forages as well as their digestibility coefficients were determined. Lignins were extracted from the fibre fractions and their ultraviolet difference spectra determined.Changes in maturity of a forage during a single growth phase, produced changes in dry-matter digestibility which were closely associated with changes in the digestibility of the cellulose and inversely related to the lignin content of the forage. Differences in digestibility between varieties of forage were less closely associated with lignin content. As the grasses matured a lignin fraction forming a difference peak at 350 mμ became evident and this was associated with decreased cellulose digestibility.Differences in voluntary food consumption resulting from changes in maturity of a single forage variety, in one growth phase, were also closely correlated with both dry matter and cellulose digestibility and inversely with lignin content. Differences between varieties and growth phases of the ryegrasses and between grasses and legumes were related less to the nature of the cellulose-lignin complex and more closely to the percentage of the total digesta deriving from cellulose.Sainfoin was characterized by the formation post-ruminally of an artifact that analysed quantitatively as lignin and qualitatively resembled a non-conjugated phenolic lignin fraction. The production of this artifact apparently disturbed fibre digestibility estimates and may have affected dry-matter digestibility estimates. Degradation of lignin apparently occurred both in the rumen and in the hind gut.

Sign in / Sign up

Export Citation Format

Share Document