The value of pepsin dry matter solubility for estimating the voluntary intake and digestibility of six Panicum varieties

1971 ◽  
Vol 11 (49) ◽  
pp. 181 ◽  
Author(s):  
DJ Minson ◽  
KP Haydock

The dry matter solubility in acid pepsin (P) was determined on 57 cuts of six Panicum varieties on which the voluntary intake (I), dry matter digestibility (D), and voluntary intake of digestible dry matter (ID) had been determined. I, D, and ID were each significantly (P<0.01) correlated with P (r = 0.67, 0.81, and 0.78). The residual standard deviation for I and ID was large due to the existence of different relations both within and between species of Panicum. The cause and the statistical implications of these biases are discussed and it was concluded that for practical purposes the method is of limited value.


1988 ◽  
Vol 68 (4) ◽  
pp. 1121-1129 ◽  
Author(s):  
W. N. MASON ◽  
P. M. FLIPOT

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



1973 ◽  
Vol 53 (2) ◽  
pp. 257-263 ◽  
Author(s):  
G. PELLETIER ◽  
E. DONEFER

Three yearling Cheviot × Suffolk ewes and three Columbia wethers were confined in metabolic cages and fed ad libitum fresh and dried marrow-stem kale (Brassica oleracea var. acephala D.C.) harvested in mid- and late October. Chemical analyses of the forages indicated no marked effects on any of the plant constituents due to drying or advancing maturity. Digestibility measurements demonstrated that marrow-stem kale (MSK) was a highly digestible material with an average dry matter digestibility of 78%. The fresh forages had higher (P < 0.05) dry matter and gross energy digestibility values than the dried form. Dry matter digestibility coefficients were higher (P < 0.05) for late October as compared with the earlier harvest. A trend toward higher (P > 0.05) voluntary intake values due to drying maturity was observed with an average relative intake of 80%. The nutritive value index averaged 65, thus indicating a digestible energy intake similar to a high-quality (legume) forage.



Agronomy ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 273 ◽  
Author(s):  
Donato Andueza ◽  
Fabienne Picard ◽  
Philippe Pradel ◽  
Katerina Theodoridou

In mountain areas, hays are the main forage in winter diets for livestock. Barn-dried hays can be an alternative to traditional hays, which are generally characterized by a low feed value. The aim of this study was to compare the feed value of barn-dried hays with that of the fresh forage from a permanent meadow. The study was carried out over three periods during the first growth cycle of the meadow’s vegetation (from 30 May to 3 June, from 13 to 17 June, and from 27 June to 1 July). Fresh forage and barn-dried hays of the same fresh forages were tested for dry matter digestibility (DMD), organic matter digestibility (OMD), and voluntary intake (VI). Both types of forage obtained each period were tested with an interval of 15 days. Chemical composition and OMD of forages did not change (p > 0.05) according to the feeding method. However, the DMD values for barn-dried hays were higher (p < 0.05) than for fresh forages at the end of the cycle. VI and digestible organic matter intake of barn-dried hays were higher (p < 0.05) than that of fresh forages. In conclusion, barn-dried hays obtained from permanent grasslands presented a higher feed value than fresh forages.



1973 ◽  
Vol 13 (61) ◽  
pp. 153 ◽  
Author(s):  
DJ Minson

On five occasions during the growing season Chloris gayana, Digitaria decumbens and Pennisetum clandestinum were fertilized with urea at 125 or 500 kg ha-1 and cut after one month's regrowth. The minimum nitrogen level in herbage was 0.96 per cent and hence voluntary intake of these feeds was not limited by a nitrogen deficiency per se. Fertilizing at the high level increased dry matter yield (P < 0.01) and depressed the leaf percentage significantly in C. gayana. Each cut was fed to ten wethers to determine digestibility and voluntary intake. The higher rate of nitrogen fertilizer increased the overall mean dry matter digestibility 2.2 per cent, organic matter digestibility 1.3 per cent and voluntary intake of dry matter 2.3 gWkg0.75 (P > 0.05). Within the harvests significant increases and decreases in digestibility and voluntary intake were found. The direction and magnitude of these changes in feeding value were not correlated with differences in yield, leaf percentage or nitrogen content.



1967 ◽  
Vol 7 (29) ◽  
pp. 546 ◽  
Author(s):  
DJ Minson ◽  
R Milford

Three experiments were conducted with sheep fed ad lib. Digitaria decumbens Stent. (Pangola grass) containing 4.4 per cent crude protein (C.P.) (experiment I), and 3.7 per cent C.P. (experiments 2, 3) and supplemented with 0, 100, 200, 400 g/day lucerne (experiments 1 and 2) and white clover (experiment 3). Both legumes were also fed ad lib. with no grass. 546 The voluntary intake of the grass in experiment 1 decreased at all levels of legume feeding. In experiment 2 the voluntary intake of the grass was increased from 607 to 844 when 200 g of legume was fed, and in experiment 3 from 653 to 843 when 100 g of legume was fed, When the voluntary intake of the grass was not limited by a crude protein deficiency, the legume had a direct replacement effect causing a depression in the voluntary intake of the Pangola grass. The dry matter digestibility increased in direct proportion to the legume percentage of the ration.



1969 ◽  
Vol 9 (39) ◽  
pp. 393 ◽  
Author(s):  
MJ Playne

Voluntary intake and dry matter digestibility of a mixture of 80 per cent spear grass hay and 20 per cent Townsville lucerne hay by sheep, in 'metabolism cages, supplemented with sodium sulphate, gluten, or sodium sulphate and gluten, were measured during a six-week experimental period. Apparent retentions of nitrogen, sodium, potassium, calcium, and phosphorus were also determined. All sheep receiving supplements gained weight whereas sheep on the basal ration lost weight. After four weeks supplementation, sheep receiving gluten alone or gluten + sodium sulphate consumed 64 per cent more feed than the control sheep, whose intake gradually declined over the experimental period. Sheep fed sodium sulphate alone consumed 48 per cent more feed than the control group. Dry matter digestibility of feed was increased by 5 to 7 percentage units when sheep were supplemented with either sodium sulphate or gluten.



1973 ◽  
Vol 13 (61) ◽  
pp. 165 ◽  
Author(s):  
PJ Michell

Neutral detergent fibre (NDF), acid detergent fibre (ADF) and water soluble carbohydrate (WSC) levels were determined on 80 samples of known apparent dry matter digestibility (DMD) and voluntary intake of dry matter (DMI). The pastures consisted of regrowths of six species: Trifolium repens (white clover cv. Grasslands Huia), Lolium perenne x L. multiflorum (short rotation ryegrass c.v Grasslands Manawa), Lolium perenne (long rotation ryegrass cv. Grasslands Ariki), Lolium perenne (perennial ryegrass cv. Tasmania No. I), Dactylis glomerata (cocksfoot cv. Currie) and Dactylis glomerata (cocksfoot cv. Grasslands Apanui), cut eight times between May 1969 and August 1970. Overall, white clover had a lower NDF and a lower WSC content than the ryegrasses but both groups had similar ADF contents. Cocksfoots had higher NDF and ADF, and lower WSC contents than the ryegrasses. NDF and ADF could be used to predict the DMD of all species in all seasons with residual standard deviations (RSD) of 3.0 and 3.2 DMD units (per cent) respectively. No significant relations (P < 0.05) were present between DMD and WSC content. Seasonal differences were present in the relations between DMI and chemical composition. The RSD of the overall regressions of intake with NDF, ADF, and WSC contents were 9.3, 9.4, and 8.9 DMI units (g/day/kg0.75) respectively. Within seasons, DMI was best predicted by regressions with detergent fibre content and here the RSD had a range of 3.4 to 5.2 DMI units. Within species over all seasons, DMI was predicted best by regressions with WSC content and the RSD had a range of 5.7 to 7.9 DMI units. The usefulness of the chemical composition measurements in explaining the reason for the low intakes, previously found with winter pasture, is discussed.



1969 ◽  
Vol 9 (40) ◽  
pp. 493 ◽  
Author(s):  
JL Lamberth

In two experiments using twin heifers with one of each pair pregnant, the effect of advanced pregnancy on the voluntary food intake, dry matter digestibility and rate of passage of food residues, was studied. In the first experiment sorghum silage was fed ad lib. In the second experiment lucerne chaff was fed at ad lib. and restricted levels and, in addition to the measurements listed above, the quantity of reticulo-rumen contents was determined in each animal. In both experiments each of the pregnant heifers ate less than their non-pregnant CO-twins, and, on analysis of all the data on ad lib. feeding, the differences were significant (P<0.01). The mean coefficients of dry matter digestibility for the pregnant heifers were significantly (P<0.01) less than those for non-pregnant heifers. This caused a significantly (P<0.01) lower intake of digestible dry matter by the pregnant heifers. Measurements of the contents of the reticulo-rumen and the rate of passage of food particles gave inconclusive results. These experiments demonstrated that there was a depression of voluntary intake in late pregnancy the cause of which is not known. This would be nutritionally significant only when the quality and voluntary intake of food were marginal.



1970 ◽  
Vol 75 (3) ◽  
pp. 369-373 ◽  
Author(s):  
R. J. Haggar ◽  
M. B. Ahmed

SUMMARYTwenty-seven sheep feeding trials were carried out on freshly cut Andropogon gayanus, fed daily during three wet seasons, 1966–8.In each year, dry-matter voluntary intake and digestibility were highest during the first part of the growing season and declined with advancing maturity of the herbage. However, at the time of ear emergence in early October, there were small increases in voluntary intake of dry-matter and crude protein digestibility, although further decreases followed after mid-October.Determinations of in vitro digestibility indicated that elongating stems during early October were at least as digestible as leaves.Seasonal changes in crude protein digestibility were much greater than changes in dry-matter digestibility; seasonal changes in feed intake were intermediate. Voluntary feed intake was related to dry-matter digestibility.Voluntary feed intake and digestible crude protein were both closely related to the crude protein content of the forage. It was concluded that crude protein is a useful criterion for predicting nutritive value.



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