scholarly journals Contrasting effects of viscous and particulate fibers on colonic fermentation in vitro and in vivo, and their impact on intestinal water studied by MRI in a randomized trial

2020 ◽  
Vol 112 (3) ◽  
pp. 595-602
Author(s):  
David Gunn ◽  
Rajani Murthy ◽  
Giles Major ◽  
Victoria Wilkinson-Smith ◽  
Caroline Hoad ◽  
...  
Keyword(s):  
Small Bowel ◽  
Wheat Bran ◽  
Gas Production ◽  
Mri Scans ◽  
Study Test ◽  
Water Trapping ◽  
Meal Ingestion ◽  
Gas Volume

ABSTRACT Background Wheat bran, nopal, and psyllium are examples of particulate, viscous and particulate, and viscous fibers, respectively, with laxative properties yet contrasting fermentability. Objectives We assessed the fermentability of these fibers in vitro and their effects on intestinal function relevant to laxation in vivo using MRI. Methods Each fiber was predigested prior to measuring gas production in vitro during 48-h anaerobic incubation with healthy fecal samples. We performed a randomized, 3-way crossover trial in 14 healthy volunteers who ingested 7.5 g fiber twice on the day prior to study initiation and once with the study test meal. Serial MRI scans obtained after fasting and hourly for 4 h following meal ingestion were used to assess small bowel water content (SBWC), colonic volumes, and T1 of the ascending colon (T1AC) as measures of colonic water. Breath samples for hydrogen analysis were obtained while patients were in the fasted state and every 30 min for 4 h following meal ingestion Results In vitro, the onset of gas production was significantly delayed with psyllium (mean ± SD: 14 ± 5 h) compared with wheat bran (6 ± 2 h, P = 0.003) and was associated with a smaller total gas volume (P = 0.01). Prefeeding all 3 fibers for 24 h was associated with an increased fasting T1AC (>75% of values >90th centile of the normal range). There was a further rise during the 4 h after psyllium (0.3 ± 0.3 s P = 0.009), a fall with wheat bran (−0.2 ± 0.2 s; P = 0.02), but no change with nopal (0.0 ± 0.1 s, P = 0.2). SBWC increased for all fibers; nopal stimulated more water than wheat bran [AUC mean (95% CI) difference: 7.1 (0.6, 13.8) L/min, P = 0.03]. Breath hydrogen rose significantly after wheat bran and nopal but not after psyllium (P < 0.0001). Conclusion Both viscous and particulate fibers are equally effective at increasing colonic T1 over a period of 24 h. Mechanisms include water trapping in the small bowel by viscous fibers and delivery of substrates to the colonic microbiota by more fermentable particulate fiber. This trial was registered at clinicaltrials.gov as NCT03263065.

The need to complement in vitro gas production measurements with residue determinations from in sacco degradabilities to improve the prediction of voluntary intake of hays

1997 ◽  
Vol 64 (1) ◽  
pp. 71-75 ◽  
Author(s):  
M. Blümmel ◽  
P. Bullerdieck
Keyword(s):  
Volume Ratio ◽  
Gas Production ◽  
Published Data ◽  
Fatty Acid Production ◽  
Residue Determination ◽  
In Vitro Gas Production ◽  
Gas Volume ◽  
In Sacco Degradability ◽  
In Sacco

AbstractThe need to complement in vitro gas production measurements with residue determination is demonstrated by the recalculation and reassessment of published data on in vitro gas production, in sacco degradabilities and voluntary dry matter intake (DMI). The in sacco degradability — gas volume ratio was determined at 24 and 48 h of incubation, termed partitioning factor (PF) and combined with rate and extent parameters of in sacco degradability and in vitro gas production to predict DMI. In vitro gas production and in sacco degradability characteristics (a + b) and c as described by the equation y = a + b(1−ect) explained 0·373 and 0·668 respectively of the variation in DMI of 19 legume and grass hays. The complementation of gas production parameters by the PF24 increased the R2 value to 0·744 with PF24 accounting for 0·407 of the variation in DMI, the rate of gas production (c) for 0·218 and the extent of gas production (a + b) for 0·119 of the variation in DMI. As a single parameter, PF48 showed the highest correlation (R2 = 0·597) with DMI but the combination of PF4S with rate and extent of in sacco or in vitro gas production measurements did not improve the correlation further, probably due to an intercorrelation between rates of fermentation and PF4S. Hays which were degraded at faster rates had higher PF values indicating proportionally higher microbial yield and lower short-chain fatty acid production per unit substrate degraded. Generally, hays with high in sacco degradabilities but proportionally low gas production i.e. hays with high PF values showed higher DMI.

Estimation of fermentable energy by the automatic in vitro gas production technique for a selection of feedstuffs incubated alone and in combination

1998 ◽  
Vol 1998 ◽  
pp. 69-69
Author(s):  
S. Fakhri ◽  
A. R. Moss ◽  
D.I. Givens ◽  
E. Owen
Keyword(s):  
Organic Matter ◽  
Incubation Period ◽  
Gas Production ◽  
Production Technique ◽  
In Vitro Gas Production ◽  
Fe Content ◽  
The Individual ◽  
Gas Volume ◽  
Selection Of

The gas production (GP) technique has previously been used to estimate the gas volume (fermentable energy (FE)) of compound feed ingredients for ruminants (Newbold et al., 1996). It was shown that the FE content of feed mixtures was represented by the combination of the total gas from the incubation of the individual feeds. However this additivity might not be consistent throughout the incubation period. The objectives were to test whether 1. other GP parameters give better estimates of FE for simple mixtures and are they additive; 2. whether organic matter apparently degraded in the rumen (OMADR) explain differences in GP; and 3. to find out if there are any other better measures than OMADR for estimating FE.

Fermentation profiles and degradability measurements in extrusa diet samples collected from brome-suppressed and undisturbed pastures and their relationship to weight gain of steers

2004 ◽  
Vol 84 (1) ◽  
pp. 105-111 ◽  
Author(s):  
M. Blümmel ◽  
E. E. Grings ◽  
M. R. Haferkamp
Keyword(s):  
Weight Gain ◽  
Gompertz Model ◽  
Gas Production ◽  
Beef Steers ◽  
N Level ◽  
Nutritive Quality ◽  
In Vitro Gas Production ◽  
Grazing Period ◽  
Gas Volume

The effects of suppression of annual bromes (Bromus japonicus Thunb. and Bromus tectorum L.) by atrazine application on the nutritive quality of extrusa diet samples (EDS) collected from the esophagus were investigated, and EDS quality estimates were compared with weight gain of grazing steers. Analysis on EDS included crude protein (CP), in vitro organic matter degradability (IVOMD), and gas production profiles in N supplemented and unsupplemented incubation media. Brome-suppression tended (P = 0.07) to increase CP content but effects on gas production kinetics and IVOMD were dependent on incubation medium N-level. In N-unsupplemented incubations, asymptotic gas production was less and rates of gas production were greater in EDS from brome-suppressed compared to undisturbed pasture. No such differences were found for N-supplemented incubations. Weight gains of steers grazing brome-suppressed pastures were 16% greater (P = 0.007) than from control pastures. The R2 for the comparison of predicted and measured gains were 0.90 (P < 0.0001), 0.96 (P < 0.0001), and 0.90 (P < 0.0001) using CP, IVOMD (N-low), and IVOMD (N-rich) as the predicting variable, respectively. Best predictions using in vitro gas production measurements were obtained from 24 h gas volume recording (R2 = 0.93, P < 0.0001). Best-fit model (sigmoidal vs. exponential) depended on grazing period and N-level, and the sigmoidal Gompertz model best described most gas production profiles. Key words: Forage quality, gas production, weight gain, beef steers

Relationship betweenin vitrogas production and neutral detergent fibre disappearance in three tropical grasses

1996 ◽  
Vol 1996 ◽  
pp. 219-219
Author(s):  
M. Herrero ◽  
N.S. Jessop
Keyword(s):  
Cell Wall ◽  
Gas Production ◽  
Adequate Description ◽  
Tropical Grasses ◽  
Neutral Detergent Fibre ◽  
Early Stages ◽  
Production Techniques ◽  
Gas Volume

In vitrogas production techniques have been used to nutritionally characterise feedstuffs for ruminants. Consideration of both the soluble and insoluble fractions has recently been shown to be essential for adequate description of cell wall disappearance (Jessop and Herrero, 1996). This study investigates how gas production measurements can be used to predict neutral detergent fibre (NDF) disappearance by correcting for the gas volume produced in the early stages of fermentation from neutral detergent solubles (NDS). The study was carried out using three tropical grasses.

Effect of non-digestible oligosaccharides in diets for weaner pigs on in vitro fermentation

1998 ◽  
Vol 1998 ◽  
pp. 30-30 ◽  
Author(s):  
J.G.M. Houdijk ◽  
B.A. Williams ◽  
S. Tamminga ◽  
M.W.A. Verstegen
Keyword(s):  
Gas Production ◽  
Production Technique ◽  
In Vitro Fermentation ◽  
Weaner Pigs

Dietary fructooligosaccharides (FOS) shifted the proportion of propionate (↑) and acetate (↓) compared to transgalactooligosaccharides (TOS) in weaner pigs' ileal digesta, both in vivo and in vitro (Houdijk et al., 1997). This could be related to different fermentation rates between these so-called non-digestible oligosaccharides (NDOs). These rates were studied via the cumulative gas production technique comparing FOS, TOS, and glucose.

scholarly journals Amphotericin B Penetrates into the Central Nervous System through Focal Disruption of the Blood-Brain Barrier in Experimental Hematogenous Candida Meningoencephalitis

2019 ◽  
Vol 63 (12) ◽  
Author(s):  
Vidmantas Petraitis ◽  
Ruta Petraitiene ◽  
Jessica M. Valdez ◽  
Vasilios Pyrgos ◽  
Martin J. Lizak ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Amphotericin B ◽  
Blood Brain Barrier ◽  
Brain Barrier ◽  
Blue Dye ◽  
Bolus Administration ◽  
Blood Brain ◽  
Mri Scans

ABSTRACT Hematogenous Candida meningoencephalitis (HCME) is a life-threatening complication of neonates and immunocompromised children. Amphotericin B (AmB) shows poor permeation and low cerebrospinal fluid (CSF) concentrations but is effective in the treatment of HCME. In order to better understand the mechanism of CNS penetration of AmB, we hypothesized that AmB may achieve focally higher concentrations in infected CNS lesions. An in vitro blood-brain barrier (BBB) model was serially infected with Candida albicans. Liposomal AmB (LAMB) or deoxycholate AmB (DAMB) at 5 μg/ml was then provided, and the vascular and CNS compartments were sampled 4 h later. For in vivo correlation, rabbits with experimental HCME received a single dose of DAMB at 1 mg/kg of body weight or LAMB at 5 mg/kg and were euthanized after 1, 3, 6, and 24 h. Evans blue dye solution (2%, 2 ml/kg) administered intravenously (i.v.) at 1 h prior to euthanasia stained infected regions of tissue but not histologically normal areas. AmB concentrations in stained and unstained tissue regions were measured using ultraperformance liquid chromatography. For selected rabbits, magnetic resonance imaging (MRI) scans performed on days 1 to 7 postinoculation were acquired before and after i.v. bolus administration of gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) at 15-min intervals through 2 h postinjection. The greatest degree of penetration of DAMB and LAMB through the in vitro BBB occurred after 24 h of exposure (P = 0.0022). In vivo the concentrations of LAMB and DAMB in brain abscesses were 4.35 ± 0.59 and 3.14 ± 0.89 times higher, respectively, than those in normal tissue (P ≤ 0.019). MRI scans demonstrated that Gd-DTPA accumulated in infected areas with a disrupted BBB. Localized BBB disruption in HCME allows high concentrations of AmB within infected tissues, despite the presence of low cerebrospinal fluid concentrations.

scholarly journals Determination of the In Vitro Gas Production and Potential Feed Value of Olive, Mulberry and Sour Orange Tree Leaves

2018 ◽  
Vol 13 (1) ◽  
pp. 269-278 ◽  
Author(s):  
Mustafa Olfaz ◽  
Unal Kilic ◽  
Mustafa Boga ◽  
Abdiwali Mohamoud Abdi
Keyword(s):  
Nutritive Value ◽  
Condensed Tannin ◽  
Gas Production ◽  
Net Energy ◽  
Sour Orange ◽  
Tree Leaves ◽  
Randomized Design ◽  
In Vitro Gas Production

AbstractThis study was conducted to determine the potential nutritive value andin vitrogas production (IVGP) parameters ofOlea europaea L. (Olive = OL),Morus alba L. (Mulberry = ML) andCitrus aurantium L. (Sour orange = SOL) tree leaves. Hohenheim gas test was used to determine thein vitrogas productions of the leaves. The gas production of samples over time was recorded for 3, 6, 9, 12, 24, 48, 72 and 96 h after incubation. Completely Randomized Design was used to compare gas production, and gas production kinetics of samples. The findings of the present study suggested that there were differences among the tree leaves in terms of crude protein, NDF,in vitrogas productions, organic matter digestibility (OMD), metabolisable energy (ME), net energy lactation (NEL) and relative feed values (RFV) (P<0.01). ML had the highest condensed tannin contents (P<0.05),in vitrogas production (IVGP), OMD and energy values (P<0.01). SOL had highest RFV values. OL showed the lowest IVGP when compared to SOL and ML. Low NDF and ADF contents of SOL would probably increase the voluntary intake, digestibility and relative feed values of these leaves by ruminants. In conclusion, it was determined that OL, ML and SOL used in the study have lowin vitrogas production and can be utilized as alternative roughage feed in ruminants. However, it is recommended that the results obtained from this research should be tested inin vivostudies.

Comparison of parameters from the Theodorou gas production technique using nitrogen-free and nitrogen-rich media as predictors of dry-matter intake and digestibility

1998 ◽  
Vol 22 ◽  
pp. 172-174
Author(s):  
D. L. Romney ◽  
F. C. Cadario ◽  
E. Owen ◽  
A .H. Murray
Keyword(s):  
Dry Matter ◽  
Gas Production ◽  
Dry Matter Intake ◽  
Production Technique ◽  
N Supply ◽  
Fermentation Method ◽  
Rich Media ◽  
Production Techniques

Parameters from in vitro gas production techniques could have potential as predictors of dry-matter intake (DMI) and digestibility. Fermentation is usually carried out under conditions where nitrogen (N) is not limiting. Therefore where N supply is a constraint to intake and digestibility, prediction equations may be inaccurate. This study compared the use of N-free and N-rich media in an in vitro fermentation method (Theodorou et al., 1994) and studied the relationships between in vitro and in vivo parameters obtained using both media.

Combining in vitro data and modelling to predict in vivo animal response

2006 ◽  
Vol 34 ◽  
pp. 135-144
Author(s):  
Jan Dijkstra ◽  
James France
Keyword(s):  
Quantitative Description ◽  
Gas Production ◽  
Biological Data ◽  
Mathematical Methods ◽  
Passage Rate ◽  
Fractional Rate ◽  
Microbial Efficiency ◽  
Definition Of

SummaryExisting feed evaluation systems for ruminants assess the feed value in a rather empirical way, with a limited ability to integrate metabolism in a meaningful framework. For the quantitative description of the mechanisms, appropriate biological data can be obtained using in vitro methods. The aim of this paper is to examine the use of modelling and in vitro data to predict digestion processes in vivo. Suitable mathematical methods are required to describe and interpret substrate disappearance profiles or gas production profiles. The derivation of such models is important since this allows a clear definition of the underlying assumptions made. Such assumptions are related to the change in fractional rate of degradation (kd) during incubation that will determine the shape of the profile. Furthermore, the value of the fractional passage rate (kp) is of crucial importance in the prediction of extent of degradation in the rumen. The development and application of models, based on classic microbial growth equations, clearly shows that observed variation in microbial efficiency in batch cultures (including the gas production technique) is not necessarily related to that in vivo. Rather, kp is again a major factor contributing to explanation of variation in microbial efficiency. Similarly, the end products of fermentation (VFA) and the VFA molar proportions can be estimated in vitro, but its direct applicability to the in vivo situation is limited. It is concluded that some potential uses of in vitro techniques are ultimately misleading. Mechanistic models indicate that mechanisms governing microbial efficiency and VFA molar proportions in vitro are not necessarily valid for the in vivo situation. Therefore, the in vitro data cannot be used directly for a uniform system of feed evaluation to predict animal responses. Rather, the in vitro data obtained for substrate degradation may be used in whole rumen models as a basal input value to indicate the degradation potential.

Comparison of inocula from sheep and cattle for thein vitrogas production technique under tropical conditions

1999 ◽  
Vol 1999 ◽  
pp. 151-151 ◽  
Author(s):  
I.C.S. Bueno ◽  
A.L. Abdalla ◽  
S.L.S. Cabral Filho ◽  
D.M.S.S. Vitti ◽  
E. Owen ◽  
...  
Keyword(s):  
Dry Matter ◽  
Rumen Fluid ◽  
Small Ruminants ◽  
Gas Production ◽  
Barley Straw ◽  
Tropical Conditions ◽  
Production Techniques ◽  
Microbial Mass

The use of small ruminants, such as sheep, in metabolism studies is more convenient as handling problems are reduced and their maintenance costs are lower, in comparison with cattle. However in vivo digestibility estimates obtained at maintenance are known to differ between these two species. With the increased use ofin vitrogas production techniques, to evaluate ruminant feedingstuffs, it is of great importance to identify whether the species from which the rumen fluid inoculum is obtained has a significant influence on the results obtained.Rumen fluid samples were obtained from a non-lactating Holstein cow (C) and six wether sheep (S) offered the same diet (80 % tropical grass and 20 % dairy concentrate) and prepared so as to have similar dry matter (DM) contents and therefore potentially the microbial mass. Nine substrates (two tropical grasses 1-2, tropical alfalfa 3, barley straw 4, and five temperate grasses 5-9) were examined.

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