An assessment of the quality of forage from its cell-wall content and amount of cell wall digested

1972 ◽  
Vol 78 (3) ◽  
pp. 355-362 ◽  
Author(s):  
K. W. Moir
Keyword(s):  
Cell Wall ◽  
Organic Matter ◽  
Ammonium Oxalate ◽  
Physical Structure ◽  
Tropical Species ◽  
Average Amount ◽  
Lignin Concentration ◽  
Digestible Organic Matter ◽  
The Difference

SUMMARYGrasses and legumes comprising poor to good quality temperate and tropical species were fed to either cattle or sheep in 36 digestibility experiments. Cell wall in these forages was the ash-free and protein-free residue after sequential extraction with acidpepsin, organic solvents and either water for grasses or ammonium oxalate for legumes. The average amount of cell wall digested per 100 g forage OM was 40·0±0·59 g in grasses and 19·8±1·85 g in legumes. It was considered that within grasses and within legumes the physiology of ruminant digestion, rather than forage quality, was the main determinant of the average amount of cell wall digested and the difference between grasses and legumes was due to interaction of the ruminant digestion process with the physical structure of the cell wall. Of forage factors governing variation about the physiological average, the total cell wall had some effect on the amount of cell wall digested, but the lignin concentration in the cell wall had no effect.Among grasses and legumes the average, apparently undigested, protein-free non-cell-wall component was 6·2±0·13 g per 100 g forage OM. This component and digestible protein relative to total protein varied among different sets of data. It was concluded that only the component of digestible organic matter which was governed by the relative proportions of cell walls and cellular contents was predictable from chemical composition. It was considered that selection in plant breeding should be based on both digestible cell wall and cell-wall content instead of digestible organic matter.

The use of cell wall organic matter components and in vitro degradability characteristics to predict intake and digestibility of white clover for sheep

1995 ◽  
Vol 46 (6) ◽  
pp. 1111 ◽  
Author(s):  
KS Nandra ◽  
VH Oddy ◽  
JF Ayres ◽  
PJ Nicholls ◽  
B Langevad ◽  
...  
Keyword(s):  
Cell Wall ◽  
Organic Matter ◽  
White Clover ◽  
Good Precision ◽  
Digestible Organic Matter ◽  
Predictive Relations ◽  
Voluntary Intake ◽  
Organic Matter Digestibility

The relations of the laboratory measurement of cell wall organic matter (CWOM) components and of the in vitro degradability characteristics of CWOM with in vivo digestibility and voluntary intake for high quality white clover were investigated. The voluntary intake, apparent digestibility and apparent rumen retention time of CWOM of white clover harvested at various stages of maturity were measured in rumen-cannulated Merino wether sheep. The in vitro degradability characteristics of CWOM of these diets were also measured. This study has quantified strong predictive relations between structural fibre constituents or degradation parameters and both digestibility and intake for white clover. The CWOM, cellulose and hemicellulose contents and potential degradability of CWOM of the white clover predicted in vivo organic matter digestibility with good precision (r2 = 0.74, 0.67, 0.72 and 0.72 respectively). The voluntary intakes of organic matter and digestible organic matter of the white clover were strongly related to CWOM, cellulose and hemicellulose contents and to the rate of degradation of CWOM in the rumen and the fits of these relations were at least as good as those predicting organic matter digestibility. The predictive equations based on CWOM: OMD (g/kg) = 97.6-0.081 (� 0.012) CWOM OMI (g/kg) = 83-0.085 (� 0.018) CWOM DOMI (g/kg) = 71.4-0.098 (� 0.015) CWOM are recommended because of the ease of analysis of CWOM in the laboratory.

Stimulation of wool growth by thyroxine implantation. II. Feed intake of grazing Merino wethers treated repeatedly with thyroxine.

1964 ◽  
Vol 15 (4) ◽  
pp. 676 ◽  
Author(s):  
LJ Lambourne
Keyword(s):  
Organic Matter ◽  
Feed Intake ◽  
Sheep Grazing ◽  
Wool Production ◽  
Wool Growth ◽  
Digestible Organic Matter ◽  
The Difference ◽  
Maintenance Requirements ◽  
Substantial Rise ◽  
Stimulation Of

Estimates have been made of the feed intake of wethers that received implantations of 60 mg thyroxine every 3 months, and of untreated sheep, grazing together. The estimated intake of digestible organic matter (D.O.M.) by treated wethers was higher than that of controls in 24 out of 27 measurement periods. The difference in feed intake was least in the iirst month after implantation, when the treated sheep lost weight, and greatest in the second and third months when the treated sheep were regaining weight. The overall increase in intake resulting from thyroxine treatment (20–25%) was greater than the increase in wool production (7% greasy weight, 3-7 % clean weight), and the efficiency of wool production was therefore lower in thyroxinetreated wethers. From the relationships between feed intake and rate of weight change it was concluded that in the month after implantation, when pulse rates indicated a substantial rise in metabolic rate, the maintenance feed requirement was raised from about 560 g to about 780 g D.O.M. per day. Observations in two winters with recently shorn sheep gave estimates of maintenance requirements for untreated wethers ranging from 850 to 1300 g D.O.M. per day. During recovery from repeated thyroxine implantation the wethers gained in weight no more efficiently than the controls. The mechanism of action of exogenous thyroxine is discussed in the light of these and other data.

The effect of different extraction procedures on the recovery of cell walls in forage and faeces from cattle and sheep

1972 ◽  
Vol 78 (3) ◽  
pp. 351-353 ◽  
Author(s):  
K. W. Moir
Keyword(s):  
Cell Wall ◽  
Organic Matter ◽  
Sequential Extraction ◽  
Cell Walls ◽  
Ammonium Oxalate ◽  
Hot Water ◽  
Sodium Sulphite ◽  
Detergent Solution ◽  
Organic Residues ◽  
Cattle And Sheep

SUMMARYForages and faeces from 28 digestibility experiments with cattle or sheep were extracted with neutral detergent solution, with and without sodium sulphite, or sequentially extracted with acid-pepsin, ethyl alcohol, diethyl ether and either ammonium oxalate or hot water. Ammonium oxalate was used to extract small amounts of non-protein material not extracted from legumes by hot water. Compared with sequential extraction the average protein-free organic residues after extraction with detergent, with and without sodium sulphite, were significantly lower in legumes and faeces, but not in grasses. The largest differences occurred in faeces from grasses for which the recoveries of cell walls as percentages of the faecal organic matter were found to be 59·2, 62·0 and 66·4 respectively, after extraction with neutral detergent plus sodium sulphite, neutral detergent alone and sequential extraction with various solvents. It was considered that the differences were due to extraction of cell-wall constituents by both detergent and sulphite.

scholarly journals Calculation of the digestibility for ruminants of roughages from their contents of cell-wall constituents. 2. Time-saving method of analysis.

1968 ◽  
Vol 16 (1) ◽  
pp. 21-24
Author(s):  
B.D.E. Gaillard ◽  
H.J. Nijkamp
Keyword(s):  
Cell Wall ◽  
Organic Matter ◽  
Standard Deviation ◽  
Correlation Coefficient ◽  
Crude Protein ◽  
Time Saving ◽  
Digestible Organic Matter ◽  
Digestible Crude Protein

For part 1, not numbered, see Abst. 3404, Vol. 37. 2. The method described here was quicker than that of part 1 for routine use, and gave the same correlation coefficient of 0.95 and standard deviation of 3.2 between the digestibility of organic matter and the estimated content of neutral detergent residue, anhydrouronic acid and lignin. The reagents and method are described in detail. Formulae for estimation of digestibility of organic matter from neutral detergent residue, lignin and anhydrouronic acid and for estimation of starch equivalent from digestible organic matter and digestible crude protein are presented.-M. S. (Abstract retrieved from CAB Abstracts by CABI’s permission)

The effect of maturity and leafiness on the intake and digestibility of alfalfas and grasses fed to sheep

1969 ◽  
Vol 73 (1) ◽  
pp. 145-154 ◽  
Author(s):  
J. E. Troelsen ◽  
J. B. Campbell
Keyword(s):  
Organic Matter ◽  
Nutritional Quality ◽  
Daily Intake ◽  
Grass Species ◽  
Digestible Organic Matter ◽  
Voluntary Intake ◽  
Alfalfa Varieties ◽  
The Relationship ◽  
Time Of Harvest

SUMMARYThe effect of maturity on the nutritional quality of hay from two alfalfa varieties and four grass species was studied. Each hay was harvested at six different stages of growth, chopped in 4–6 cm lengths, and fed to sheep in quantities of 10% in excess of voluntary intake. The relationship between intake (Y) and digestibility (X) of dry matter was best expressed by regressions of the form: Y = a + b1X + b2X2. The rate of intake declined 1·5 g daily per kg0·75 of body weight per unit decrease in digestibility percentage, and was the same for both alfalfa and grass hays. However, the intake of alfalfa hay was about 10% higher than that of the grass hays of similar digestibility. No differences in the relationship between intake and digestibility (P < 0·05) were observed between the two alfalfa varieties or between the four grass species. When the nutritional quality was expressed as voluntary intake of digestible organic matter daily per kg0·75 of body weight, and time of harvest as day-number of the year, the difference in quality between the six kinds of hay was very small or absent at the beginning of the season (immature to prebloom) and increased toward maturity (dough stage to seed ripe). The decline in quality of alfalfa hay was slower than that of grass hay, and ceased at the mature to overripe stage. On the average, voluntary intake of digestible organic matter declined 0·29 g daily for each day delay in harvest time; this decline varied from 1·2% of the daily intake of digestible organic matter in the beginning of the season to 0·6% at the mature stage. Time of harvest ‘accounted for’ 77–89% of the variation in the quality of the hays. The confounded effect of maturity and leanness on the nutritional quality of the hays was expressed best by concave, second degree polynomial regressions. On the average a unit decline in percent leaves corresponded to a decline of 0·58 g and 0·73 g respectively in the daily intake of digestible organic matter from alfalfa and grass hay. This varied from over 1 g early in the season to less than one tenth of a gram late in the season. The confounded effect of leafiness and growth stage ‘accounted for’ over 75% of the variability in nutritional quality. The relationship between intake and digestibility of the alfalfa and grass hays was used to illustrate how voluntary intake of metabolizable energy (percent of requirement for maintenance) from hay of pure or mixed species may be predicted from in vitro digestibility.

scholarly journals Examination of the Quality of the Manual Pre-Sterilization Processing of Dental Instruments Using Benzidine Test

2016 ◽  
Vol 43 (2) ◽  
pp. 52-60
Author(s):  
V. Stoeva ◽  
A. Kevorkyan ◽  
R. Raycheva ◽  
V. Kondeva ◽  
Y. Stoilova
Keyword(s):  
Organic Matter ◽  
Ultrasonic Cleaning ◽  
Dental Instruments ◽  
The World ◽  
Dental Practices ◽  
The Difference

Summary The risk of infections in dental practices has been attracting for decades the interest of researchers from all over the world. A serious problem related to the transmission of blood-borne viruses is the thorough removal of organic matter, and mainly blood, from dental instruments when performing manual pre-sterilization decontamination. Application of benzidine test to prove the presence of blood traces on large and small dental instruments prepared for sterilization for the purpose of assessing the quality of the manual pre-sterilization decontamination. A total of 485 benzidine tests had been performed on selected 205 large and 280 small dental instruments visibly contaminated with blood. Of the total of 485 tested samples, blood traces were found in 63 (12.99 ± 1.53%). In the group of large instruments, positive benzidine test was obtained in 7.80% compared to 16.78% in the small instruments with the difference being statistically significant (p = 0.003). All 63 positive samples were additionally processed using ultrasound. Blood traces were found in 8 instruments with all of the positive samples being obtained from the barbed broaches. The manual cleaning does not guarantee decontamination of the dental instruments unlike the ultrasonic cleaning where any blood traces are being completely removed from the large instruments. In terms of the small instruments, there are still blood traces present after the ultrasonic cleaning which requires for it to be combined with a suitable enzyme cleaner, and the barbed broaches, as a requirement, should be used on a disposable basis.

Wool growth of pregnant and lactating Merino ewes

1985 ◽  
Vol 105 (3) ◽  
pp. 613-622 ◽  
Author(s):  
V. H. Oddy
Keyword(s):  
Organic Matter ◽  
Fibre Diameter ◽  
Wool Fibre ◽  
Total Plasma ◽  
Wool Growth ◽  
Digestible Organic Matter ◽  
Pregnancy And Lactation ◽  
The Difference ◽  
The Relationship ◽  
Growth Deficit

SUMMARYThe wool production of pregnant, lactating and non-pregnant, non-lactating (dry) Merino ewes eating one of three diets: chaffed oaten hay (OH), chaffed lucerne hay (LH), and a 50/50 (w/w) mixture of OH and LH, was determined. Measurements were made for 2 months prior to mating, during pregnancy and for 3 months after lambing, and for the dry ewes over the same period.Production of clean wool (Y, g/day) by dry ewes was linearly related to digestible organic matter intake (X, g/day):Y = 0·0301 X - 3·34, r = 0·97.Clean wool growth was significantly less (P < 0·01) than dry ewes in the 4th and 5th month of pregnancy and throughout lactation. During pregnancy the total deficit in clean wool growth (calculated as the difference between observed wool growth and that expected on the basis of the relationship between feed intake and clean wool growth of dry ewes) was 456 g for ewes bearing a single lamb and 578 g for those bearing twins, with no difference between diets. In lactation the total clean wool growth deficit increased as milk production increased, and for every litre of milk produced there was a deficit of 12 g clean wool.Wool fibre diameter was reduced during the 1st month of lactation. There was no consistent effect of pregnancy or lactation on the number of wool follicles per mm2, the ratio of primary plus secondary to primary wool follicles, or on the thickness of skin on the midside.Digestibility of dietary organic matter (DOM) was reduced during the last 3 months of pregnancy, and the first 2 months of lactation. However, this was insufficient to account for the magnitude of the decrease in wool growth seen during pregnancy and lactation.Wool sulphur content increased during pregnancy (P < 0·001), but not during lactation. The relationship between total plasma cyst(e)ine concentration and DOM intake during pregnancy was similar to that in dry ewes, but during lactation total plasma cyst(e)ine concentration was less than expected. It was calculated that during pregnancy the amount of sulphur saved through reduced wool growth was greater than that deposited in the conceptus, and during lactation the amount of sulphur saved in reduced wool growth matched that excreted as milk.These results are discussed in relation to control of wool growth during pregnancy and lactation.

scholarly journals Stability and stabilisation of biochar and green manure in soil with different organic carbon contents

Soil Research ◽  
2010 ◽  
Vol 48 (7) ◽  
pp. 577 ◽  
Author(s):  
Joseph M. Kimetu ◽  
Johannes Lehmann
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Green Manure ◽  
Labile Organic Matter ◽  
Aggregate Fraction ◽  
The Status ◽  
The Difference ◽  
The Stability ◽  
Poor Soil

Due to its recalcitrance against microbial degradation, biochar is very stable in soil compared to other organic matter additions, making its application to soils a suitable approach for the build-up of soil organic carbon (SOC). The net effects of such biochar addition also depend on its interactions with existing organic matter in soils. A study was established to investigate how the status of pre-existing soil organic matter influences biochar stabilisation in soil in comparison to labile organic additions. Carbon loss was greater in the C-rich sites (C content 58.0 g C/kg) than C-poor soils (C content 21.0–24.0 g C/kg), regardless of the quality of the applied organic resource. Biochar-applied, C-rich soil showed greater C losses, by >0.5 kg/m2.year, than biochar-applied C-poor soil, whereas the difference was only 0.1 kg/m2.year with Tithonia diversifolia green manure. Biochar application reduced the rate of CO2-C loss by 27%, and T. diversifolia increased CO2-C losses by 22% in the C-poor soils. With biochar application, a greater proportion of C (6.8 times) was found in the intra-aggregate fraction per unit C respired than with green manure, indicating a more efficient stabilisation in addition to the chemical recalcitrance of biochar. In SOC-poor soils, biochar application enriched aromatic-C, carboxyl-C, and traces of ketones and esters mainly in unprotected organic matter and within aggregates, as determined by Fourier-transform infrared spectroscopy. In contrast, additions of T. diversifolia biomass enriched conjugated carbonyl-C such as ketones and quinones, as well as CH deformations of aliphatic-C mainly in the intra-aggregate fraction. The data indicate that not only the stability but also the stabilisation of biochar exceeds that of a labile organic matter addition such as green manure.

The voluntary intake and digestibility by cattle and sheep of dried grass wafers containing particles of different size

1972 ◽  
Vol 14 (2) ◽  
pp. 177-188 ◽  
Author(s):  
R. J. Wilkins ◽  
C. R. Lonsdale ◽  
R. M. Tetlow ◽  
T. J. Forrest
Keyword(s):  
Organic Matter ◽  
Alimentary Tract ◽  
Fine Particles ◽  
Binding Agent ◽  
Milled Material ◽  
Digestible Organic Matter ◽  
Low Modulus ◽  
Voluntary Intake ◽  
The Difference ◽  
Cattle And Sheep

SUMMARYWafers of dried grass which differed in particle size (modulus of fineness) were prepared and fed ad libitum to cattle and sheep. The response of the two classes of stock to the feeds was similar. The digestibility of organic matter and of cellulose decreased with decrease in modulus of fineness (more fine particles) and this was associated with more rapid passage of the finely-milled material through the alimentary tract. Organic matter intake generally increased with decrease in modulus of fineness, but the pattern of response differed between experiments. In one experiment the difference in voluntary intake between feeds with modulus of fineness of 2·5 and 1·0 was less than 5% and not significant, but in a second experiment the intake of feed with modulus of fineness of 2·1 was 18% lower than that of feed with modulus of fineness of 1·0. In the first experiment the wafers broke down during handling and feeding with the result that the feed of low modulus of fineness was extremely dusty, but in the second experiment a binding agent was included and little breakdown of wafers occurred. It is suggested that dustiness may have restricted the intake of some of the feeds in the first experiment. Intakes of digestible organic matter did not differ significantly between treatments in either experiment.

The relationship between the cell-wall constituents of roughages and the digestibility of the organic matter

1962 ◽  
Vol 59 (3) ◽  
pp. 369-373 ◽  
Author(s):  
Blanche D. E. Gaillard
Keyword(s):  
Molecular Structure ◽  
Cell Wall ◽  
Organic Matter ◽  
Strong Correlation ◽  
Strongly Correlated ◽  
Crude Fibre ◽  
Marked Rise ◽  
Digestible Organic Matter ◽  
The Relationship

There is a strong correlation between the digestibility of the organic matter and the percentage crude fibre, percentage lignin, and percentage cellulose plus lignin in the foodstuffs examined.There is evidence that the holocellulose and xylan in grasses are different from those in legumes in the extent to which they are digested. It is suggested that this is due mainly to the xylans or hemicellulose fraction in the forages, and may be a reflexion of a different molecular structure for the xylans in either group.Within each group of plants both the holocellulose and xylan percentages are strongly correlated to the percentage digestible organic matter.Excessive heating of hay led to a marked rise in the percentage lignin. This is probably due to the xylans becoming horny and insoluble, therefore being determined as lignin. This also offers an explanation for the decrease in digestibility of the organic matter.

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