scholarly journals ABSORPTION AND UTILIZATION OF VOLATILE FATTY ACIDS IN RUMINANTS

1984 ◽  
Vol 64 (5) ◽  
pp. 354-355 ◽  
Author(s):  
N. A. MacLEOD ◽  
E. R. ØRSKOV
Keyword(s):  
Fatty Acids ◽  
Acetic Acid ◽  
Fatty Acid ◽  
Key Words ◽  
Osmotic Pressure ◽  
Volatile Fatty Acid ◽  
Volatile Fatty Acids ◽  
Fatty Acid Utilization ◽  
Molar Percent

VFA absorption was investigated in sheep and cattle nourished by intragastric infusions. No differences in absorption were observed between the mixtures of VFA studied. However, unlike osmotic pressure, pH affected the relative proportions of VFA found in the rumen. At pH 7.0 the proportions found resembled those infused; at pH 5.3 acetic acid was 10 molar percent higher. Key words: Ruminant, intragastric volatile fatty acid utilization

Studies on the production of volatile fatty acids from grass by rumen liquor in an artificial rumen: II. The volatile fatty acid production from dried grass

1957 ◽  
Vol 49 (2) ◽  
pp. 171-179 ◽  
Author(s):  
A. John ◽  
G. Barnett ◽  
R. L. Reid
Keyword(s):  
Fatty Acids ◽  
Acetic Acid ◽  
Propionic Acid ◽  
Metabolic Pathways ◽  
Volatile Fatty Acid ◽  
Volatile Fatty Acids ◽  
Water Soluble ◽  
Fatty Acid Production ◽  
Growing Seasons ◽  
Titration Curves

1. A study has been made of the production of volatile fatty acids obtainable from dried grass and its gross water-soluble and water-insoluble separates, in the artificial rumen, over two growing seasons.2. In contradistinction to fresh grass, the dried grass gives a consistent production of acetic acid proportionately greater than propionic acid, at all stages of maturity, but when aqueous extracts of the dried grass, and the resultant extracted grass, respectively, are examined separately in the artificial rumen, it is found that the former yield preponderating amounts of acetic acid while the latter give amounts of propionic acid equal to, or exceeding, the corresponding productions of acetic acid.3. An examination of the titration curves for the total acids obtained from the dried grass, extracted grass and grass extract runs, indicates an approach to an incomplete relationship between the residual carbohydrate in the extracted grass and cellulose, while the grass extract reveals itself as the chief source of acetic acid in the whole dried grass, the acid being formed very speedily at the start of the run.4. The suggested sources and some of the possible metabolic pathways involved in the formation of v.f.a. from grass are discussed in the text.

FERMENTATION OF WHEAT OR LUPINS IN THE RUMEN OF SHEEP

1984 ◽  
Vol 64 (5) ◽  
pp. 29-30 ◽  
Author(s):  
R. W. HODGE ◽  
M. J. WATSON ◽  
C. KAT
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Key Words ◽  
Volatile Fatty Acid ◽  
Ammonia Nitrogen ◽  
Total Volatile ◽  
Volatile Fatty Acid Concentration ◽  
Branched Chain Fatty Acids ◽  
Branched Chain ◽  
Total Volatile Fatty Acid

The concentration of ammonia nitrogen and branched chain fatty acids was significantly higher (P < 0.05) in ruminal fluid of sheep given lupins than in those given wheat but there were no significant differences in pH, total volatile fatty acid concentration or molar proportions of acetate, propionate or butyrate. Key words: Sheep, wheat, lupins, rumen, fermentation

Rates of production of volatile fatty acids in the rumen. V. Evaluation of fodders in terms of volatile fatty acid produced in the rumen of the sheep

1967 ◽  
Vol 18 (4) ◽  
pp. 625 ◽  
Author(s):  
FV Gray ◽  
RA Weller ◽  
AF Pilgrim ◽  
GB Jones
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Volatile Fatty Acid ◽  
Volatile Fatty Acids ◽  
Night Time ◽  
Digestible Energy ◽  
Significant Difference ◽  
Freely Moving

l(a). Volatile fatty acid (VFA) production (moles/12 hr) by two sheep fed at 2-hourly intervals on a constant ration containing equal parts of wheaten hay and lucerne hay, showed no significant difference between the sheep or between day-time and night-time values. The precision with which production could be measured over a series of 12-hr periods is given. The quantities of VFA produced in the rumen on successive days varied considerably; the extent of this variation was similar to that occurring in the quantities of faeces passed. (b) Production remained much the same whether the sheep were fed at intervals of 1, 2, or 12 hr. (c) The energy of the VFA produced in the rumen was equivalent to about 54% of the digestible energy of the diet. 2. Similar amounts of VFA were produced from two different mixtures of wheaten hay and lucerne hay, and from lucerne hay alone. 3. A modification in the procedure for measuring VFA production was tested and found to be satisfactory. The necessary apparatus could be readily carried on the back of a freely moving sheep.

Identification of the volatile fatty acid in the peripheral blood and rumen of cattle and the blood of other species

1951 ◽  
Vol 2 (1) ◽  
pp. 92 ◽  
Author(s):  
GL McClymont
Keyword(s):  
Acetic Acid ◽  
Fatty Acid ◽  
Propionic Acid ◽  
Butyric Acid ◽  
Peripheral Blood ◽  
Molecular Basis ◽  
Volatile Fatty Acid ◽  
Volatile Fatty Acids ◽  
Bovine Blood ◽  
Mean Values

Volatile fatty acid isolated from nine samples of peripheral blood from four cows contained, on a molecular basis, from 90.0 to 97.0 per cent. of acetic acid (mean 93.3 per cent.). The remainder comprised, as mean values, propionic acid, 2.39 per cent.; butyric acid, 2.61 per cent.; and a group of at least three acids between butyric and octanoic, 1.84 per cent. The significance of the high proportion of acetic acid in the volatile fatty acid of bovine peripheral blood is discussed. Only traces of esterified acids lower than octanoic could be found in bovine blood lipides. Volatile fatty acids were found also in the blood of the rabbit, guinea pig, horse, and pig and in human plasma. Here again a high proportion of acetic acid was recorded. Volatile fatty acid isolated from nine samples of ruminal contents from two cows contained on a molecular basis from 52.3 to 69.0 per cent. of acetic acid (mean 60.0 per cent.). The remainder comprised, as mean values, propionic acid, 21.8 per cent.; butyric acid, 14.4 per cent.; and acids higher than butyric (apparently largely valeric and hesanoic), 3.8 per cent. This limited number of analyses indicated no gross effect of type of feed on the proportion of the acids in the rumen.

scholarly journals Activation of volatile fatty acids in bovine liver and rumen epithelium. Evidence for control by autoregulation

1973 ◽  
Vol 136 (2) ◽  
pp. 311-319 ◽  
Author(s):  
R. Ash ◽  
G. D. Baird
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Volatile Fatty Acid ◽  
Volatile Fatty Acids ◽  
Bovine Liver ◽  
Mitochondrial Matrix ◽  
Rumen Epithelium

1. The total capacities of homogenates of bovine liver and rumen epithelium to activate acetate, propionate and butyrate were determined. 2. Activating capacities were assayed by measuring the rate of formation of the corresponding CoA esters. The methods used for determining the concentrations of the CoA esters allowed the CoA esters of acetate, propionate and butyrate to be distinguished. It was thus possible to investigate the effect of the presence of a second volatile fatty acid on the rate at which a given volatile fatty acid was activated. 3. The propionate-activating capacity in rumen epithelium was decreased by about 87% in the presence of butyrate, the acetate-activating capacity in liver was decreased by about 55% in the presence of either propionate or butyrate, and the butyrate-activating capacity in liver was decreased by about 40–50% in the presence of propionate. 4. All three activating capacities in liver appeared to be located in the mitochondrial matrix and membrane. The three activating capacities had similar locations to each other in rumen epithelium as well, although in this case activity was more evenly divided between the mitochondria and the cytoplasm. 5. The relative activating capacities towards the volatile fatty acids in the two tissues, together with the ability of one volatile fatty acid to inhibit the activation of another volatile fatty acid, appear to ensure that butyrate is mainly metabolized in the rumen epithelium and that propionate is metabolized in the liver.

Studies on the production of volatile fatty acids from grass by rumen liquor in an artificial rumen: III. A note on the volatile fatty acid production from crude fibre and grass cellulose

1957 ◽  
Vol 49 (2) ◽  
pp. 180-183 ◽  
Author(s):  
A. John ◽  
G. Barnett ◽  
R. L. Reid
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Acid Production ◽  
Volatile Fatty Acid ◽  
Volatile Fatty Acids ◽  
Relative Yield ◽  
Water Soluble ◽  
Cellulose Powder ◽  
Crude Fibre ◽  
Fatty Acid Production

1. The findings presented in two previous papers on the yields of volatile fatty acids, obtained by the action of rumen liquor in the artificial rumen, from fresh grass, dried grass and the water-soluble and water-insoluble separates of the latter, have been amplified by a consideration of the acids similarly obtained from specimens of chemically prepared crude fibre and cellulose, from four of the dried grass specimens.2. The proportions of different volatile fatty acids from grass crude fibre and grass cellulose resemble those obtained from cellulose powder, propionic acid being produced in greatest relative yield.3. A general review of these latter findings, in relation to those already presented, has been given.

Microbial metabolism in the forestomachs and the large intertine of sheep

1965 ◽  
Vol 16 (1) ◽  
pp. 77 ◽  
Author(s):  
VJ Williams
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Water Content ◽  
Large Intestine ◽  
Volatile Fatty Acid ◽  
Dry Matter ◽  
Volatile Fatty Acids ◽  
Wheat Grain ◽  
Maize Grain ◽  
The Individual

Sheep were fed on either lucerne chaff, high wheat grain, or high maize grain rations. Analyses were made on digesta from the rumen and large intestines of cannulated and slaughtered animals. The results for the large intestine showed that, when equal quantities of dry matter are given, the composition of the ration can affect the pH, the water content, and the total dry matter of the digesta; diet can also affect the total quantities of volatile fatty acid and ammonia in the organ.The proportions of the individual volatile fatty acids in the caecal fluid were not affected by the different diets fed in this experiment. The data did not suggest any consistent pattern in the pH or in the concentrations of ammonia and volatile fatty acid in the caecal fluid during the 24 hr between feeds.

Bio-augmentative volatile fatty acid production from waste activated sludge hydrolyzed at pH 12

RSC Advances ◽  
2015 ◽  
Vol 5 (62) ◽  
pp. 50033-50039 ◽  
Author(s):  
Xue Yang ◽  
Lei Wen ◽  
Xiang Liu ◽  
Si Chen ◽  
Yayi Wang ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Activated Sludge ◽  
Acid Production ◽  
Volatile Fatty Acid ◽  
Volatile Fatty Acids ◽  
Waste Activated Sludge ◽  
Soluble Complex ◽  
Fatty Acid Production ◽  
Hydrolysis Of

Although many pretreatment methods are employed to enhance the hydrolysis of waste activated sludge (WAS), the bioconversion of soluble complex substrates needs improvement to produce higher volatile fatty acids (VFAs).

scholarly journals The determination of volatile fatty acids in the caecum of the conscious rabbit

1976 ◽  
Vol 35 (3) ◽  
pp. 365-371 ◽  
Author(s):  
D. S. Parker ◽  
R. T. Mcmillan
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Volatile Fatty Acid ◽  
Acid Level ◽  
Volatile Fatty Acids ◽  
Fatty Acid Content ◽  
Diurnal Fluctuation ◽  
Fatty Acid Level ◽  
Conscious Rabbit

1. A method of obtaining dialysed samples from the caecum of the conscious rabbit is described.2. Values for total volatile fatty acid content and for molar proportions of individual volatile fatty acids in dialysate samples were in good agreement with those obtained from caecal material.3. The volatile fatty acid level in the caecum throughout the day was determined using two groups of animals, one group fed ad lib. and the other group on a restricted food intake. These results indicated a marked diurnal fluctuation in volatile fatty acid level in the caecum of rabbits fed once/d which was not evident in those fed ad lib.

Volatile fatty acid metabolism of ruminants, with particular reference to the lactating bovine mammary gland and the composition of milk fat

1951 ◽  
Vol 2 (2) ◽  
pp. 158 ◽  
Author(s):  
GL McClymont
Keyword(s):  
Fatty Acids ◽  
Acetic Acid ◽  
Mammary Gland ◽  
Fatty Acid ◽  
Milk Fat ◽  
Volatile Fatty Acid ◽  
Close Association ◽  
Blood Levels ◽  
Acid Uptake ◽  
Bovine Mammary Gland

Studies are reported on the volatile fatty acid (V.F.A.) metabolism of sheep and bovines with particular reference to the association between (i) ingestion of food and ruminal levels of V.F.A.s and arterial levels of acetic acid and (ii) the utilization of arterial acetic acid by the bovine mammary gland and the association between this utilization and the proportion of lower fatty acids (Reichert-Meissl value) in the milk fat. Ruminal levels of V.F.A. and arterial levels of acetic acid were found to be similar in cattle and sheep, and similar to those reported by earlier workers for sheep. There was a close association between changes in ruminal V.F.A. and arterial acetic acid levels. Arterial acetic acid levels were found on the feeds studied to reach a maximum value of 8-14 mg. per cent. by 2-5 hours after feeding, declining to 5-8 mg. per cent. by 8 hours after feeding and to 2-6 mg. per cent. by 16 hours after feeding. On starvation for approximately 72 hours, values fell as low as 1.5 mg. per cent. Acetic acid was found to be a major metabolite of the bovine mammary gland, arterio-venous (A-V.) differences being directly dependent on the arterial level and of the order of 2-6 mg. per cent. or 40-80 per cent. of the arterial level in the fed animal. Arterial levels and mammary A-V. differences of acetic acid were unaffected by cod-liver oil feeding or low roughage-high concentrate diets, both of which depressed the fat percentage and the Reichert- Meissl (R-M.) value of the milk fat. Hyperinsulinism and recent or delayed milking also had no effect on the A-V. differences. The depression in R-M. value during fasting was not reversed by intraruminal or intravenous acetic acid infusions despite the maintenance of high blood levels of acetic acid. There was no detectable correlation between carbon dioxide output by the mammary gland and the acetic acid uptake of the gland, indicating that the acid served some 'useful' purpose in the gland. It is concluded, taking into account other evidence, that acetic acid is utilized in the gland for fat synthesis and oxidation, depending on the requirements of the gland, but that the proportion of lower fatty acids in milk fat is not dependent on the uptake of acetic acid.

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