Effect of volatile fatty acids, lactic acid and ammonia on rumen pH in sheep

1957 ◽  
Vol 8 (6) ◽  
pp. 674 ◽  
Author(s):  
PK Briggs ◽  
JP Hogan ◽  
RL Reid
Keyword(s):  
Lactic Acid ◽  
Fatty Acid ◽  
Volatile Fatty Acid ◽  
Volatile Fatty Acids ◽  
Salivary Secretion ◽  
Ammonia Nitrogen ◽  
Soluble Carbohydrate ◽  
Nitrogen Levels ◽  
Rumen Ph ◽  
Wide Range

Data are presented on pH, volatile fatty acid, lactic acid, and ammonia nitrogen levels in the rumen of sheep being hand-fed on a wide range of diets. It is concluded that the rumen pH rarely falls outside the range 5.0-7.5 on diets on which lactic acid never accumulates in the rumen after feeding. On such diets rumen pH is closely related to the volatile fatty acid level. Evidence is presented which indicates that the pH-volatile fatty acid relationship on different diets may be considerably modified by variations in salivary secretion and in the accumulation of ammonia nitrogen in the rumen after feeding. The contribution of ammonia nitrogen to the total buffering capacity of the rumen is discussed. Lactic acid only accumulated in the rumen on diets containing high levels of soluble carbohydrate or starch. Lactic acid levels above 20 mM were always associated with pH levels below 3.0, but although levels higher than 80 mM were often recorded, lumen pH levels never fell below 4.33. On these diets rumen pH was closely related to the level of volatile fatty acid or lactic acid or both in the rumen.

scholarly journals Determining the optimal dose of virginiamycin for ruminal parameters and performance of Nellore cattle on pasture

2018 ◽  
Vol 39 (4) ◽  
pp. 1749
Author(s):  
João Alexandrino Alves Neto ◽  
Ivanna Moraes de Oliveira ◽  
Matheus Henrique Moretti ◽  
Paloma Helena Gonçalves ◽  
Michele Aparecida Prado Alves ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Volatile Fatty Acid ◽  
Total Concentration ◽  
Block Design ◽  
Average Daily Gain ◽  
Optimal Dose ◽  
Ammonia Nitrogen ◽  
Experimental Unit ◽  
Tropical Pasture ◽  
Tropical Conditions

There are no studies evaluating the virginiamycin (VM) doses under tropical conditions. So, the present study was conducted to evaluate the optimal dose of VM for growing Nellore bulls on tropical pasture. Two experiments were conducted. The first experiment, one hundred and two Nellore bulls (307 ± 25 kg body weight [BW]; 22 months) were used. Animal performance was evaluated using a randomized block design, with group as experimental unit (n = 8; 12 animals each). The second experiment, a double 4 × 4 Latin square, eight animals were used to evaluate the ruminal parameters. Four doses were evaluated: 0, 35, 55, and 75 mg VM per 100 kg BW. The average daily gain (P = 0.08) and carcass gain (P = 0.05) exhibited a trend of quadratic behavior. An increased dose of VM did not affect supplement intake (P = 0.64), rumen pH (P = 0.96), acetate: propionate ratio (P = 0.73), or the total concentration of volatile fatty acid (P = 0.63). The concentration of rumen ammonia nitrogen exhibited a quadratic effect (P = 0.01). A quadratic behavior was found for volatile fatty acid, except for propionate (P < 0.01). In conclusion, the dose of 47 mg VM per 100 kg BW is recommend for growing Nellore bulls on tropical pasture.

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.

Effect of treatment with sodium hydroxide on the feeding value of oat and rape straw for sheep

1985 ◽  
Vol 36 (4) ◽  
pp. 623 ◽  
Author(s):  
JB Coombe ◽  
JG Mulholland ◽  
RI Forrester
Keyword(s):  
Organic Matter ◽  
Fatty Acid ◽  
Volatile Fatty Acid ◽  
Rape Straw ◽  
Rumen Ph ◽  
Volatile Fatty Acid Concentration ◽  
N Utilization ◽  
Feeding Value ◽  
Naoh Treatment

Oat and rape straws were treated with NaOH (70 and 40 g kg-1, respectively) by spraying with NaOH solutions (20 or 12.5% w/w), consolidating the sprayed straw into stacks, and storing under plastic. After storage for up to 60 weeks, in vitro digestibilities had been approximately doubled, although it appeared that the reaction was complete by 4 weeks. Potential digestibility of straw organic matter estimated by a polyester bag technique, was increased by c. 0.1 by NaOH treatment but the rate of digestion in the rumen was not changed. Following storage, treated and untreated straws were dried, ground, mixed with supplements and pelleted for feeding to sheep. Mixtures of treated or untreated oat straw, minerals, c. 3% urea and 0, 14, 28 or 42% starch were fed to mature wethers. The main effects of NaOH treatment of straw were to increase water intake, digestibilities of organic matter and cellulose, and rumen volatile fatty acid levels, and decrease rumen ammonia levels. Low intakes of NaOH-straw with no added starch were associated with high rumen pH (> 7.5 , probably due to unreacted alkali (equivalent to 23 g NaOH kg-1). Inclusion of starch, but not NaOH-straw treatment, improved dietary N utilization, although mean N balances were negative (- 5.5 to - 0.1 g day-1) on all diets. Feeding treated straw increased the amounts of Na eaten, and of Na and P apparently absorbed; the extra absorption was accounted for by increased urinary excretion so that retention was not increased. When diets of rape straw supplemented with urea and minerals were fed to 2-year-old wethers, NaOH treatment of straw increased intakes of food and water, organic matter digestibility, rumen volatile fatty acid concentration and N balance.

Volatile fatty acid production in aerobic thermophilic pre-treatment of primary sludge

1997 ◽  
Vol 36 (11) ◽  
pp. 189-196 ◽  
Author(s):  
K. B. McIntosh ◽  
J. A. Oleszkiewicz
Keyword(s):  
Fatty Acid ◽  
Flow Rate ◽  
Volatile Fatty Acid ◽  
Volatile Fatty Acids ◽  
Final Concentration ◽  
Anoxic Condition ◽  
Fatty Acid Production ◽  
Primary Sludge ◽  
Soluble Organic Carbon ◽  
Pre Treatment

The efficiency of volatile fatty acid (VFA) production in a thermophilic aerobic digester (TAD) process using primary sludge was studied under two oxygenation states and detentions times ranging from 12 to 24 hours. The highest VFA concentration increase occurred in the 18 hour anaerobic aerated digester (O2 flow rate: 0.025 m3/m3·h; ORP: less than -300 mV) from 0.047 mg HAc/mg VSS in the feed to 0.106 mg HAc/mg VSS in the effluent. The anoxic condition (O2 flow rate: 0.14 m3/m3·h; ORP: between 0 to -225 mV) resulted in VFA utilisation and a final concentration of only 0.001 mg HAc/mg VSS. Under the anaerobic aerated condition, acetic acid constituted the largest fraction of short chain volatile fatty acids at an average of 60.4% and propionic trailed at 19.3%. The fraction of butyric and valeric acids were 12.2% and 8.1% respectively. It was found that with a decreasing oxygen supply and a decreasing detention time (HRT), the soluble organic carbon to ammonia ratio (SOC:NH3) increased.

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.

scholarly journals Anaerobic digestion of catering wastes: effect of micronutrients and retention time

2008 ◽  
Vol 57 (5) ◽  
pp. 687-692 ◽  
Author(s):  
M. A. Climenhaga ◽  
C. J. Banks
Keyword(s):  
Fatty Acid ◽  
Retention Time ◽  
Volatile Fatty Acid ◽  
Loading Rate ◽  
Ammonia Nitrogen ◽  
Organic Loading Rate ◽  
Micronutrient Supplementation ◽  
Anaerobic Digesters ◽  
Fried Foods ◽  
Prolonged Retention

Source-separated foodwastes collected from a campus catering facility were processed in bench-scale single-stage anaerobic digesters. The feedstock contained a varied mix of fruits, vegetables, meats and fried foods. A constant organic loading rate (OLR) was maintained with differing hydraulic retention times (HRT). Regular addition of trace elements or prolonged retention time allowed stable digestion at high total volatile fatty acid (TVFA) levels. Reactors on HRT of 25, 50, and 100 days with no micronutrient supplementation exhibited methanogenic failure after approximately 40, 100 and 90 days respectively, while duplicate reactors with micronutrient supplementation maintained stable digestion. An extended HRT of 180 days has so far allowed continued digestion (for reactors with and without micronutrient supplementation) at levels of ammonia nitrogen exceeding 5.7 g l−1 and volatile fatty acid levels exceeding 15 g l−1, usually considered inhibitory or toxic.

Sign in / Sign up

Export Citation Format

Share Document