THE PRODUCTION OF ORGANIC ACIDS IN THE PIG: I. THE EFFECT OF DIET ON THE PROPORTIONS OF VOLATILE FATTY ACIDS IN PIG FECES

1962 ◽  
Vol 42 (1) ◽  
pp. 55-62 ◽  
Author(s):  
D. W. Friend ◽  
J. W. G. Nicholson ◽  
H. M. Cunningham

Experiments were conducted to determine the effect of diet, level of feeding and age and/or weight on the proportions of volatile fatty acids (VFA) in the feces of pigs. Cellulose was added to the control ration fed in one experiment and dried whey or bran to that fed in another experiment. When the level of intake of the cellulose-supplemented ration was reduced, the digestibility of crude fiber in the ration increased. The proportion of fecal acetic acid also increased, but the difference observed did not reach statistical significance at P = 0.05. Differences in the proportion of acetic, butyric and valeric acid due to cellulose supplementation of the control ration were statistically significant (P < 0.05). The whey and the bran-supplemented rations gave statistically significant differences (P < 0.05 or P < 0.01) for the proportions of fecal valeric, propionic or acetic acid. The proportions of fecal VFA appeared to be relatively unaffected by the age and/or weight of pigs from weaning to market weight.

2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 146-147
Author(s):  
Rachel Kort ◽  
Gage E Nichols ◽  
Caitlin E Evans ◽  
Julia P Holen ◽  
Haley Wecker ◽  
...  

Abstract The objective of the first experiment was to determine the effects of corn particle size on the diet apparent total tract digestibility (ATTD) of protein (CP), digestible energy (DE), metabolizable energy (ME) and N-corrected ME (AMEn) in addition to estimating the ME of corn in gestating sows. A total of 27 sows, during the second phase of gestation, were fed a common diet manufactured with corn ground to one of 3 target particle sizes (dgw): 400, 800, or 1200 µm. Titanium dioxide (0.25%) was included in the diet as an indigestible marker for digestibility calculations. Sows were fed experimental diets for 7 days to allow for diet adaptation before a 2-day collection period of urine and fecal samples. Reducing dgw of corn from 1,200 to 400 µm increased (linear, P &lt; 0.01) ATTD CP and GE, DE, ME, AMEn and calculated ME of corn. The objective of the second experiment was to determine the effects of corn particle size on the total concentration and molar proportions of volatile fatty acids (VFA) in the feces of gestating sows. A total of 27 sows were fed treatments similar to Exp. 1 from day 61 to 82 of gestation. On day-82 and 83 of gestation, 2 fecal grab samples were collected for VFA analyses. Sows fed diets with decreasing corn dgw had increased (quadratic, P = 0.021) fecal acetic acid proportions, and decreased propionic (quadratic, P = 0.019) and valeric acid (P = 0.005). In conclusion, for every 100 µm decrease in corn dgw from 1,200 to 400 µm, corn ME value increased by 28.6 kcal/kg. Additionally, decreasing corn particle size led to an increase in the proportion of acetic acid and a decrease in propionic and valeric acid in fecal samples of gestating sows.


1952 ◽  
Vol 29 (1) ◽  
pp. 57-65 ◽  
Author(s):  
F. V. GRAY ◽  
A. F. PILGRIM ◽  
H. J. RODDA ◽  
R. A. WELLER

1. The mixture of volatile fatty acids in the rumen of the sheep has been shown to include formic acid, acetic acid, propionic acid, n-butyric acid, iso-butyric acid, n-valeric acid, another valeric acid isomer, caproic acid and an acid which is probably heptoic acid. The proportions in which they are present have been determined. 2. When acetic acid labelled with 14C in the carboxyl group was incorporated in the rumen fermentation in vitro, active carbon appeared later in all the higher acids. When labelled propionic acid was included in the fermentation, active carbon appeared in the valeric but not in the butyric acid. The results suggest a synthesis of the higher acids by condensation of the lower ones with 2-C compound in equilibrium with acetic acid. The extent of such syntheses and other possible modes of origin of the fatty acids are discussed.


1963 ◽  
Vol 61 (1) ◽  
pp. 109-114 ◽  
Author(s):  
K. El-Shazly ◽  
A. R. Abou Akkada ◽  
M. M. A. Naga

1. Fourin vitrofermentation experiments, in duplicate, were carried out over 24 hr. periods, to estimate the production of v.f.a. and o.a from forages.2. A new technique for determining the total organic acids produced in the rumen is described.3. The o.a. produced in the earlier part of the fermentation are considerably higher than the v.f.a. but the difference then diminishes. There is practically no difference in the amounts produced after 24 hr.4. Highly significant correlations were found between thein vitroproduction of v.f.a. or o.a. and d.e./kg. d.m., for all the roughages tested. Nonlegumes gave a more highly significant correlation than legumes.5. Regression equations show that o.a. or v.f.a. were more accurate thanin vitrocellulose digestion for predicting the d.e./kg. d.m. of non-legume forages. It is concluded that V.F.A. productionin vitrois the best criterion in this respect.


1968 ◽  
Vol 19 (5) ◽  
pp. 791 ◽  
Author(s):  
GJ Faichney

Experiments are reported in which sheep were given roughage diets or a high concentrate diet and the VFA absorbed from the rumen were estimated by an in vitro fermentation procedure. The VFA absorbed were compared with the digestible and metabolizable energy intakes of the sheep, determined in digestibility trials, for each diet. For a lucerne diet, a straw diet, and the high concentrate diet the proportions of the digested energy absorbed as VFA were 33.6, 42.4, and 33.2% respectively. On the lucerne diet, the difference between the mean molar proportions of the VFA absorbed and the mean molar proportions of the VFA in the rumen approached significance for acetic acid (P < 0.10) and was highly significant for butyric acid (P < 0.01). The differences were not significant for the other diets.


Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 108
Author(s):  
Yichong Wang ◽  
Sijiong Yu ◽  
Yang Li ◽  
Shuang Zhang ◽  
Xiaolong Qi ◽  
...  

Nutritional strategies can be employed to mitigate greenhouse emissions from ruminants. This article investigates the effects of polyphenols extracted from the involucres of Castanea mollissima Blume (PICB) on in vitro rumen fermentation. Three healthy Angus bulls (350 ± 50 kg), with permanent rumen fistula, were used as the donors of rumen fluids. A basic diet was supplemented with five doses of PICB (0%–0.5% dry matter (DM)), replicated thrice for each dose. Volatile fatty acids (VFAs), ammonia nitrogen concentration (NH3-N), and methane (CH4) yield were measured after 24 h of in vitro fermentation, and gas production was monitored for 96 h. The trial was carried out over three runs. The results showed that the addition of PICB significantly reduced NH3-N (p < 0.05) compared to control. The 0.1%–0.4% PICB significantly decreased acetic acid content (p < 0.05). Addition of 0.2% and 0.3% PICB significantly increased the propionic acid content (p < 0.05) and reduced the acetic acid/propionic acid ratio, CH4 content, and yield (p < 0.05). A highly significant quadratic response was shown, with increasing PICB levels for all the parameters abovementioned (p < 0.01). The increases in PICB concentration resulted in a highly significant linear and quadratic response by 96-h dynamic fermentation parameters (p < 0.01). Our results indicate that 0.2% PICB had the best effect on in-vitro rumen fermentation efficiency and reduced greenhouse gas production.


DUST-BORNE TRACE GASES AND ODORANTS The analysis of dust-borne trace gases requires their i-solation from the dust particles. Procedures for the isolation and characterization of trace gases and odorants in the dust from pig houses are given by SCHAEFER et al. (29), HAMMOND et al.(30) and TRAVIS and ELLIOTT (31). Alcoholic solvents were found to be effective for the extraction of volatile fatty ac­ ids and phenols from the dust of hen (32) and pig houses (33), (34). Today, gas chromatography is usually used for the sepa­ ration and identification of the trace gases. Table IV gives a literature review of compounds identified in the dust of pig houses. There are only very few reports on investigations on the dust from hen houses (32). Most of the odours coming from livestock production units are associated with the biological degradation of the animal wastes (35), the feed and the body odour of the animals (1). Volatile fatty acids and phenolic compounds were found to con­ tribute mostly to the strong, typical odour of animal houses by the help of sensory evaluations parallel to the chemical analysis (29),(30). Table V gives quantitative values of volatile fatty acids and phenolic/indolic compounds found in the aerosol phase and in settled dust of piggeries, respectively. The results from the aerosol phase coincide, particularly as far as acetic acid is concerned. For the investigations of the settled dust the coefficients of variation (CV) and the relative values (%) characterizing the percentage of the single compounds as part of the total amount are quoted. The values are corrected with the dry matter content of the dust. Main components are acetic acid and p-cresol, respectively. Table VI compares results from air, dust and slurry in­ vestigations on VFA and phenolic/indolic compounds in piggeries. Relative values are used. When comparing the results derived from investigations on dust, air or slurry it is necessary to use relative values because of the different dimensions, for experience shows that in spite of large quantitative differ­ ences between two samples within the group of carboxylic acids and within the group of phenolic/indolic compounds the propor­ tions of the components remain rather stable (36). In the group of VFA acetic acid is the main component in air, dust, and slurry followed by propionic and butyric acid. The other three acids amount to less than 25%. In the group of phenols/ indoles p-cresol is the main component in the four cited in­ vestigations. However, it seems that straw bedding can reduce the p-cresol content; in this case phenol is the main compo­ nent , i nstead (37 ). 4. EMISSION OF DUST-BORNE VFA AND PHENOLS/INDOLES FROM PIGGERIES The investigations of dust from piggeries show that both VFA and phenols/indoles are present in a considerable amount. However, compared to the air-borne emissions calculated on the base of the results of LOGTENBERG and STORK (38) less than the tenth part (1/10) of phenols/indoles and about the hundredth part (1/100) of VFA are emitted by the dust, only. Table VII compares the dust-borne and air-borne emissions of VFA and


CytoJournal ◽  
2015 ◽  
Vol 12 ◽  
pp. 23 ◽  
Author(s):  
Nora K. Frisch ◽  
Yasin Ahmed ◽  
Seema Sethi ◽  
Daniel Neill ◽  
Tatyana Kalinicheva ◽  
...  

Background: ThinPrep® (TP) cervical cytology, as a liquid-based method, has many benefits but also a relatively high unsatisfactory rate due to debris/lubricant contamination and the presence of blood. These contaminants clog the TP filter and prevent the deposition of adequate diagnostic cells on the slide. An acetic acid wash (AAW) protocol is often used to lyse red blood cells, before preparing the TP slides. Design: From 23,291 TP cervical cytology specimens over a 4-month period, 2739 underwent AAW protocol due to initial unsatisfactory smear (UNS) with scant cellularity due to blood or being grossly bloody. Randomly selected 2739 cervical cytology specimens which did not undergo AAW from the same time period formed the control (non-AAW) group. Cytopathologic interpretations of AAW and non-AAW groups were compared using the Chi-square test. Results: About 94.2% of the 2739 cases which underwent AAW were subsequently satisfactory for evaluation with interpretations of atypical squamous cells of undetermined significance (ASCUS) 4.9% (135), low-grade squamous intraepithelial lesions (LSIL) 3.7% (102), and high-grade squamous intraepithelial lesions (HSIL) 1% (28). From the 2739 control cases, 96.3% were satisfactory with ASCUS 5.5% (151), LSIL 5.1% (139), and HSIL 0.7% (19). The prevalence of ASCUS interpretations was similar (P = 0.33). Although there were 32% more HSIL interpretations in the AAW group (28 in AAW vs. 19 in non-AAW), the difference was statistically insignificant (P = 0.18). AAW category; however, had significantly fewer LSIL interpretations (P = 0.02). The percentage of UNS cases remained higher in the AAW group with statistical significance (P < 0.01). Conclusions: While AAW had a significantly higher percent of UNS interpretations, the protocol was effective in rescuing 94.2% of specimens which otherwise may have been reported unsatisfactory. This improved patient care by avoiding a repeat test. The prevalence of ASCUS and HSIL interpretations between AAW and non-AAW groups were comparable. Though not statistically significant, HSIL interpretations were relatively higher in the AAW group. LSIL interpretations showed lower prevalence in AAW group.


2017 ◽  
Vol 21 (1) ◽  
pp. 26 ◽  
Author(s):  
EllIN HARlIA HARlIA ◽  
MARlINA ET ◽  
MASITA R ◽  
RAHMAH KN

The natural methane formed by bacteria in anaerobic conditions is known as biogenic gas. Gas trapped in coal, formed through thermogenesis as well as biogenesisis known as coal-bed methane (CBM). The availability of organic material as decomposition of this material into methane is continuously required for the production of methane in the coal aquifer. The aim of this research was to investigate whether or not cattle feces bacteria were able to grow and produce methane in coal. Parameters measured were Volatile Fatty Acids (VFA) and the production of biogas, such as nitrogen, hydrogen, carbon dioxide, and methane. Explorative method was used and data obtained was analyzed by descriptive approach. The results showed that the bacteria found in the feces survived in the coal and produce biogas. On day 2 when the process was at the acidogenesis phase, it produced VFA with the largest component of acetic acid. Acetic acid would undergo decarboxylation and reduction of CO2 followed by reactions of H2and CO2 to produce methane (CH4) and carbon dioxide (CO2) as the final products. ,


2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Ruiling Gao ◽  
Zifu Li ◽  
Xiaoqin Zhou ◽  
Wenjun Bao ◽  
Shikun Cheng ◽  
...  

Abstract Background Volatile fatty acids (VFAs) can be effective and promising alternate carbon sources for microbial lipid production by a few oleaginous yeasts. However, the severe inhibitory effect of high-content (> 10 g/L) VFAs on these yeasts has impeded the production of high lipid yields and their large-scale application. Slightly acidic conditions have been commonly adopted because they have been considered favorable to oleaginous yeast cultivation. However, the acidic pH environment further aggravates this inhibition because VFAs appear largely in an undissociated form under this condition. Alkaline conditions likely alleviate the severe inhibition of high-content VFAs by significantly increasing the dissociation degree of VFAs. This hypothesis should be verified through a systematic research. Results The combined effects of high acetic acid concentrations and alkaline conditions on VFA utilization, cell growth, and lipid accumulation of Yarrowia lipolytica were systematically investigated through batch cultures of Y. lipolytica by using high concentrations (30–110 g/L) of acetic acid as a carbon source at an initial pH ranging from 6 to 10. An initial pH of 8 was determined as optimal. The highest biomass and lipid production (37.14 and 10.11 g/L) were obtained with 70 g/L acetic acid, whereas cultures with > 70 g/L acetic acid had decreased biomass and lipid yield due to excessive anion accumulation. Feasibilities on high-content propionic acid, butyric acid, and mixed VFAs were compared and evaluated. Results indicated that YX/S and YL/S of cultures on butyric acid (0.570, 0.144) were comparable with those on acetic acid (0.578, 0.160) under alkaline conditions. The performance on propionic acid was much inferior to that on other acids. Mixed VFAs were more beneficial to fast adaptation and lipid production than single types of VFA. Furthermore, cultures on food waste (FW) and fruit and vegetable waste (FVW) fermentate were carried out and lipid production was effectively improved under this alkaline condition. The highest biomass and lipid production on FW fermentate reached 14.65 g/L (YX/S: 0.414) and 3.20 g/L (YL/S: 0.091) with a lipid content of 21.86%, respectively. By comparison, the highest biomass and lipid production on FVW fermentate were 11.84 g/L (YX/S: 0.534) and 3.08 g/L (YL/S: 0.139), respectively, with a lipid content of 26.02%. Conclusions This study assumed and verified that alkaline conditions (optimal pH 8) could effectively alleviate the lethal effect of high-content VFA on Y. lipolytica and significantly improve biomass and lipid production. These results could provide a new cultivation strategy to achieve simple utilizations of high-content VFAs and increase lipid production. Feasibilities on FW and FVW-derived VFAs were evaluated, and meaningful information was provided for practical applications.


1957 ◽  
Vol 49 (2) ◽  
pp. 171-179 ◽  
Author(s):  
A. John ◽  
G. Barnett ◽  
R. L. Reid

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.


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