Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “DIGESTION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 955 records · Page 53Linked to original sources
PubMed1989

Digestion of fibre polysaccharides of pea (Pisum sativum) hulls, carrot and cabbage by adult cockerels.

Characterization of the carbohydrates of pea (Pisum sativum) hulls, carrot and cabbage using both colorimetric and gas-liquid chromatographic techniques permitted a detailed investigation into the extent of digestion of differing types of fibre. These digestion studies were greatly aided by the development of a rapid bioassay employing starved adult cockerels. Total collection of undigested residues, uncontaminated by food spillage, could be made from trays placed under the cockerels. Chemical analysis showed that pea hulls consisted mainly of fibre with very little available carbohydrate present, whereas more than half of freeze-dried carrot and cabbage consisted of available carbohydrate (sucrose, glucose, fructose, starch) and consequently considerably less fibre was present. The fibre of carrot and cabbage was similarly composed of nearly equal amounts of neutral and acidic polysaccharides, whereas pea-hull fibre had four times as much neutral as acidic polysaccharides. The digestibility of total neutral polysaccharides from all three foodstuffs was extremely low. However, there appeared to be preferential digestion of polysaccharides composed of rhamnose, arabinose and galactose residues, all associated with pectic material, in contrast to the indigestibility of polysaccharides composed of fucose, xylose and glucose. Acidic polysaccharides were digested to a greater extent than neutral ones, and those of carrot and cabbage more so than pea hulls. The polysaccharides which were the most soluble were also the most digestible, but due to the arbitrariness of polysaccharide solubility, quantification of their total digestibility per se was considered not possible.

Animals↗
PubMed1991

Nutrient digestibilities in ingredients fed alone or in combinations.

Digestibility coefficients (DC) of protein, dry matter, energy, starch, and dietary fibre in individual feedstuffs were used to predict the DC in feed mixtures. Digestibility studies with growing rats involved six feed sources: soya-bean meal, barley, rapeseed meal, peas, wheat bran and wheat, given individually and in various combinations, i.e. fourteen diets in total. True digestibility of protein (TD) and apparent digestibility of starch could be predicted in feed mixtures from their respective DC values for the individual ingredients, except in the diet composed of peas + barley. Dry matter (DM) and insoluble dietary fibre digestibilities in the mixtures could also be calculated from their individual DC values. Energy digestibility could be predicted in all mixtures except for barley + wheat and peas + wheat. Although the discrepancies were significant, the differences were not great. The digestibility of soluble dietary fibre in the mixtures could be predicted as for the individual ingredients in all but three diets: rapeseed meal + barley, peas + barley and peas + wheat. The results confirm that DC values for TD, DM, energy, starch and dietary fibre in mixtures can be calculated with high precision from DC determined from individual ingredients. Caution should be taken though when mixtures contain a high amount of dietary fibre, especially of the soluble type.

Animal Feed↗
PubMed1992

Effect of fibre level, particle size and adaptation period on digestibility and rate of passage as measured at the ileum and in the faeces in the adult rabbit.

The use of specific methods other than gravimetric ones to analyse fibre permitted a more precise study of the degradation of cell wall (CW) in the digestive tract. Digesta flow and rate of passage measurements have not been assessed previously in rabbits to investigate fibre digestion and fibre effects simultaneously in the proximal and in the distal segments of the tract. The effect of the level of dietary fibre on ileal and overall digestibility and rate of passage were studied by comparing semi-purified diets containing only one source of CW (dehydrated lucerne (Medicago sativa) meal) given to adult female rabbits. The effect of fibre particle size and adaptation period were also investigated. Measurements of fibre composition using both colorimetric and gas-liquid chromatographic techniques, showed that large amounts of (CW) were degraded in the caecocolic segments. Increasing dietary fibre level reduced the rate of passage but fibre degradation was increased, at the same time a lower digestive efficiency for energy in the small intestine was found. A small quantity of CW was apparently degraded before the caecum, assuming that the water-soluble fraction of CW was essentially implicated. Grinding lucerne meal through a 1 mm instead of a 3 mm screen did not improve CW digestibility in spite of a longer rate of passage in the caeco-colic segments. Adaptation to a high-fibre diet resulted in an higher digestive volume for colon and caecum, related to an improved degradation of CW. Furthermore, digestive efficiency in the small intestine appeared higher for rabbits adapted to a high-fibre diet than that for rabbits initially fed on a low-fibre diet.

Adaptation, Physiological↗
PubMed2005

Postprandial glycaemic, lipaemic and haemostatic responses to ingestion of rapidly and slowly digested starches in healthy young women.

The objective of the present study was to investigate the postprandial metabolism of two starches with contrasting rates of hydrolysis in vitro. Characterized using the Englyst method of in vitro starch classification, C*Set 06 598 contained predominantly rapidly digestible starch and C*Gel 04 201 contained predominantly slowly digestible starch. Each test starch, naturally enriched with 13C, was fed to ten healthy female volunteers as part of a moderate fat test meal (containing 75 g test starch and 21 g fat), in a double-blind randomized crossover design. The metabolic response to each starch was measured after an overnight fast, in an acute 6 h study, before and after 14 d of daily consumption of 75 g test starch. During each acute study, blood samples were taken at 15 min intervals for the first 2 h and at 30 min intervals for the remaining 4 h. Breath 13CO2 enrichment was measured at the same time points and indirect calorimetry was performed for 20 min every 40 min immediately before and throughout the study. Significantly more rapid, greater changes in postprandial plasma glucose, NEFA and serum insulin concentrations were observed after consumption of the rapidly digestible starch. Breath 13CO2 output over the first 3-4 h rose rapidly then began to decline following consumption of the rapidly digestible starch, but plateaued for the slowly digestible starch. The 14 d adaptation period did not affect any of the glycaemic or lipaemic variables but there was a reduction in postprandial plasminogen activator inhibitor-1 concentrations. These data confirm that starches characterized as predominantly rapidly digestible versus slowly digestible by the Englyst procedure provoke distinctly different patterns of metabolism postprandially.

Adult↗
PubMed2003

Evaluation of apparent ileal digestibility of amino acids in Chinese corn by-products for growing-finishing pigs.

Twelve crossbred barrows (BW 47 +/- 2.81 kg) were fitted with a T-cannula in the terminal ileum and fed one of ten diets containing corn gluten meal, dried distillers grain or dried distillers grain with solubles as the sole protein source, according to a 6 x 6 Latin Square design. Lysine, tryptophan and methionine were, the first, second and third limiting amino acids in these by-products. The ileal apparent digestibility of methionine, tyrosine, leucine and phenylalanine in corn gluten meal was high. The ileal apparent digestibility of tryptophan, tyrosine and leucine differed significantly in corn gluten meal. The ileal apparent digestibility of amino acids was higher in dried distillers grain with solubles than in dried distillers grain. To predict the ileal apparent digestibility of tryptophan, methionine and threonine linear regression equations were derived. The results suggested that processing technique can influence the ileal apparent digestibility ofamino acids in corn by-products. It was concluded that the direct technique cannot accurately determine the ileal apparent digestibility of tryptophan in dried distillers grain with solubles and dried distillers grain, due to its low content. The content of an amino acid in a feedstuff used as the sole source of protein must meet the minimum requirement of pigs when the ileal apparent digestibility of constituent amino acids is determined using the direct technique.

Amino Acids↗
PubMed2004

Effect of dehulling of rapeseed on feed value and nutrient digestibility of rape products in pigs.

In the presented study the influence of dehulling rapeseed on the composition of rapeseed meal (RM) and rapeseed cake (RC) and on its feed value for piglets and growing-finishing pigs was investigated. Before withdrawal of oil, rapeseed (variety Express) was dehulled applying a procedure developed by SKET GmbH Magdeburg and the Section Food-Technology of the University Essen. The steps of the dehulling procedure were described. For RM the oil was removed by the prepress-solvent procedure till a crude fat content of 2.1% in DM. RC was produced by pressing only resulting approximately 13% crude fat in DM. The RM and RC from not dehulled (ND) and dehulled (D) rapeseed were examined analytically. Crude nutrients, sugar and fibre substances, amino acids, some minerals and trace elements, fatty acids, glucosinolates and sinapine, and phytate were determined. By dehulling the seed the crude fibre content was decreased in RM and RC by approximately 40%. The ADF content declined by 35 and 39%, and the NDF content by 28% and 40% in RM and RC, respectively. The decrease in ADL content amounted to 50% and 65% for RM and RC, respectively. On the other hand, the CP content of RM and RC was increased by 7% and 13%, respectively, by dehulling the seed while the amino acid content of rape protein increased only slightly. The contents of glucosinolates and sinapine were also increased by dehulling, while the contents of phytate and phytate P were decreased. In digestibility and balance experiments with piglets and intact hybrid breeds of growing-finishing pigs, the digestibility of organic matter and of crude nutrients and the contents of digestible energy and metabolizable energy were estimated. Furthermore, the precaecal digestibility of crude nutrients and amino acids was determined with fistulated mini-pigs. By dehulling the seeds the digestibility of organic matter from RM and RC was improved in piglets and adult pigs by approximately 10%, and the ME contents increased by 13-15%. The precaecal digestibility of the sum of amino acids was increased by approximately 3 and 6 units in RM and RC, respectively. The precaecal digestibility of lysine in RM and RC reached that of soybean oil meal from not dehulled beans.

Amino Acids↗
PubMed2001

Nutrient digestibility and intestinal viscosities in broiler chickens fed on wheat diets, as compared to maize diets with added guar gum.

1. Three maize diets containing 0, 1 or 3 g of guar gum per kg and 2 wheat diets were given to male broiler chickens for measurements of growth performance and nutrient digestibility. 2. The intestinal viscosities found with wheat diets were within the range of those observed with the 3 maize diets. The correlations between in vivo and in vitro viscosities were higher with real than with potential applied viscosity. 3. The gain:food ratio decreased (P < 0.05) with the addition of 3 g guar gum/kg. The mean gain:food ratio observed for wheat diets was lower (P = 0.007) than the mean value found for the 3 maize diets. 4. The negative effects of increased intestinal viscosity due to guar gum addition on nutrient digestibility were highest for lipids and lowest for starch. 5. Wheat diets resulted in much lower (P < 0.001) starch apparent digestibility compared to maize diets with added guar gum despite similar mean intestinal viscosities in the 2 groups of diets. Apparent lipid digestibility with wheat diets was lower (P < 0.01) than the value predicted from intestinal viscosity, the predictive model having been calculated with the guar gum added maize diets. Apparent protein digestibility did not differ between wheat diets and guar gum added maize diets. 6. It was concluded that the low apparent digestibilities of starch and lipid observed with wheats could not be attributed only to intestinal viscosity and that other factors appear to be implicated in the low digestibilities observed with the wheat samples tested in the present experiment.

Animal Feed↗
PubMed2002

Effects of sources of protein and enzyme supplementation on protein digestibility and chyme characteristics in broilers.

1. The purpose of this study was to evaluate the effects of protein source and enzyme supplementation on protein digestibility and chyme characteristics in broilers. 2. One hundred and twenty growing (13 d old) and 60 finishing (34 d old) Arbor Acre strain commercial male broilers were selected and placed into individual metabolic cages. 3. The experiment was a 5 x 2 factorial arrangement with 5 different sources of protein: casein, fish meal, soybean meal (SBM), soy protein concentrate (SPC), maize gluten meal (MGM) and two levels of protease (bromelain), 0 and 65 CDU/kg diets. 4. The diets were iso-nitrogenous and semi-purified, with Cr2O3 as an indicator for determination of ileal digestibility and chyme characteristics. 5. Apparent ileal protein digestibility (AIPD) in both growing and finishing chickens was highest on the casein diet, followed by fish meal, SBM, SPC and MGM. 6. Enzyme inclusion did not improve protein digestibility, but significantly decreased the digesta pH value in the gizzard and increased pH in the ileum in the 3-week-old broilers. 7. The digesta pH values in the gizzard and duodenum were significantly lower in the SBM and fish meal groups compared with the other protein groups. The molecular weight distribution pattern of the soluble protein in the chyme of the gastrointestinal (GI) segments showed a similar trend, regardless of the enzyme inclusion or the stage of growth. 8. The molecular weight profile of soluble protein changed dynamically in the casein fed broilers from the gizzard to ileum and the low molecular weight proteins, < 7 kDa, reached maximum levels at the ileum. The molecular weight profile of the soluble protein in the SBM and SPC changed between the jejunum and the ileum and in the intermediate molecular soluble protein weight (7 to 10 kDa) was significantly decreased. This indicated that the hydrolysis process began from the middle to the posterior end of the small intestine. 9. Similar profiles were also shown with fish meal protein. The pattern of distribution, however, did not show any prominent change in the GI segments of the MGM group. 10. The pepsin, trypsin and chymotrypsin protease activity in the gizzard and duodenum were highest in the casein group and lowest in the MGM group as compared with the other protein groups. 11. The rate change in the patterns of molecular weight distribution in soluble protein and the digestive enzyme activity provide indications of the partial digestibility of different protein sources. The exogenous enzyme, bromelain, did not show any beneficial effect on protein digestion.

Animals↗
PubMed1995

Contribution of oligosaccharide and polysaccharide digestion, and excreta losses of lactic acid and short chain fatty acids, to dietary metabolisable energy values in broiler chickens and adult cockerels.

1. Two experiments were conducted, using both adult cockerels from a layer strain and 3-week-old broiler chickens. In the first experiment, one of the 2 diets investigated was composed mainly of maize and soyabean meals, the other one containing the latter ingredients diluted with 475 g/kg mature pea seeds. For these 2 diets, the apparent metabolisable energy values corrected to 0 nitrogen retention (AMEn) were derived, together with the apparent digestibilities of nitrogen, amino acids, total lipids, starch, individual oligosaccharides, and non-starch polysaccharides (NSP). Excretions of lactic acid and short chain fatty acids (SCFA) were also determined. 2. In the first experiment, the mean apparent digestibilities of starch, lipids, total amino acids, NSP, sucrose and alpha-galacto-oligosaccharides in adult cockerels were 0.946, 0.785, 0.835, 0.045, 0.99 and 0.99, respectively. In broiler chickens, they were 0.938, 0.675, 0.830, -0.016, 0.988 and 0.867, respectively. The bird type effects were significant (P < 0.05) for the digestibilities of starch, lipids, NSP (for the maize-soyabean meal diet, only) and alpha-galacto-oligosaccharides. Broiler chickens excreted a mean of 11.032 g organic acids/kg diet against 4.190 in adult cockerels (P < 0.001). These digestibility measurements enabled the contribution made by each dietary component to the AMEn value of the diets to be calculated. AMEn values were lower in broiler chickens than in adult cockerels, with on average 0.8 MJ/kg dry matter difference resulting from bird type. This difference was accounted for by differences between bird types in energy supplied by lipids (34.0%), starch (7.5%), alpha-galacto-oligosaccharides (8.7%), NSP (14.2%), and in energy losses from lactic acid excretion (16.4% of the difference in AMEn between bird types). 3. In the second experiment 2 diets were studied, consisting of a basal and the basal diluted with 30 g/kg lactose (a fermentable sugar in chickens) and 12 g/kg of a water-soluble gel-forming component containing 50% polygalacturonic acids. Lactose digestibilities reached 0.928 and 0.712 in adult cockerels and chickens, respectively. The digestibilities of the water-soluble polygalacturonic acids were similar in cockerels and broiler chickens, with a mean value of 0.672. Figures similar to those of the first experiment were found in the comparison between cockerels and broiler chickens, for the AMEn values of diets, the digestibilities of starch and lipids and the excretion of lactic acid. Broiler chickens excreted 4.580 g lactic acid/kg dry food intake, compared with 0.740 g in the adult.(ABSTRACT TRUNCATED AT 400 WORDS)

Aging↗
PubMed2004

Peptic digestibility of raw and heat-coagulated hen's egg white proteins at acidic pH range.

Allergenicity in food proteins is generally dependent on their heat stability and resistance to digestive enzymes together with the presence of IgE-recognizing epitopes on the molecules. Using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting, we assessed peptic digestibility of raw and heat-coagulated hen's egg white proteins at acidic pH range (1.5-4.0). Ovalbumin in raw egg white was slightly digested by pepsin at pH 1.5 and pH 2.0, and was almost resistant to the enzyme at pH 2.5 and over, which was altered in heat-coagulated egg white at the pH range from 1.5 to 2.5 where the protein was well digestive against the enzyme. Peptic digestibility of ovomucoid in raw egg white was good at the pH range from 1.5 to 2.5, but almost non-existent at pH 3.0 and over where the improvement of the digestibility of the protein was not found even in heat-coagulated egg white. As the stomach in new born infants shows a low amount of secretary pepsin and an out of optimum pH of peptic activity, low digestibility of ovalbumin and ovomucoid in raw and heat-coagulated egg white at over pH 3.0 is supposed to be responsible for their allergenicity and delayed outgrowth from hen's egg allergy in patients with delayed maturation of stomach functions.

Animals↗
PubMed2005

In vitro carbohydrate digestibility of whole-chickpea and chickpea bread products.

Pulses such as the chickpea are generally considered to be valuable dietary sources of slowly digestible starch, a form of starch that is considered beneficial to health since it results in relatively low post-meal blood glucose levels compared with more rapidly digested starch. The development of novel chickpea-based foods is necessary to help expand the worldwide consumption of the chickpea. However, the effect of different processing methods on the starch digestibility of chickpea-based foods has not been widely investigated. This study used an in vitro method simulating human carbohydrate digestion to determine levels of slowly digestible starch, rapidly digestible starch (RDS), resistant starch, total starch and rapidly available glucose (RAG) of: (i) whole-chickpea products (domestically boiled, commercially canned and commercially precooked/vacuum-packaged); and (ii) standard white bread, chickpea flour bread (25% replacement of wheat flour by chickpea flour) and extruded chickpea flour bread (25% replacement of wheat flour by extruded chickpea flour). The RAG levels were then used to predict the relative in vivo glycaemic indices of the products. The commercially precooked/vacuum-packaged whole chick peas demonstrated higher levels of RDS than the commercially canned and domestically boiled products (P<0.05). In addition, the domestically boiled product had lower levels of RAG (g/100 g available carbohydrate) compared with the canned and precooked/vacuum-packaged products (P<0.05). There were no significant differences between any of the carbohydrate digestibility measures of the white bread, chickpea flour bread and extruded chickpea flour bread (P>0.05) and all bread products demonstrated far higher RAG (g/100 g available carbohydrate) values than the whole-chickpea products. The findings suggest that the commercially precooked/vacuum-packaged whole chick peas and the canned product may have higher and less beneficial glycaemic indices than the domestically boiled chick peas. It appears unlikely that the use of chickpea flour or extruded chickpea flour, at the incorporation rate investigated in this study, would modify the glycaemic index of bread. It is probable, however, that the chickpea bread products investigated would demonstrate higher and potentially less beneficial glycaemic indices than the whole-chickpea products.

Bread↗
PubMed1984

[Relations between apparent fecal and apparent ileal crude protein digestibility in swine].

The crude protein and lysine digestibility values available in literature and ascertained in comparative investigations at the end of the small intestine (distal ileum) and in the complete digestive tract (faeces analysis method) of pigs were subjected to a correlation calculation in order to find out whether and to what degree there are relations between apparent 'ileal' and apparent 'faecal' digestibility. For both crude protein and lysine the relation between ileal and faecal digestibility is so close (r = 0.73 resp. 0.85 ... 0.98) so that for practical purposes it is not necessary to determine the apparent ileal digestibility for each feedstuff by means of the complicated cannula method. This can be calculated with great reliability from the experimentally ascertained apparent faecal digestibility. The differences between faecal and ileal digestibility are smaller for lysine (conversion factors 0.92 ... 0.99) than for crude protein (conversion factors 0.89 ... 0.93).

Animal Feed↗
PubMedDate not supplied

[The effect of different levels of soybean extract meal on the apparent digestibility of crude nutrients and amino acids in colostomized laying hens].

Four colostomized laying hens per group were given a ration of barley and soya bean oil meal (SBM) with 12.5, 25.0 and 37.5% SBM resp. The crude protein intakes were 14.0, 17.7 and 21.4 g per animal and day. The lysine intake raised from 681 mg (group 1) to 1275 mg (group 3) per animal and day. The digestibility of dry matter and of the N-free extracts of the ration decreased with the rising SBM portion in the ration. The digestibility of crude protein remained constant. The investigated amino acids (Lys, His, Arg, Cys, Met) were higher digested in the 37.5% SBM ration than in the 12.5% SBM ration. The following digestibility values for SBM were found by means of the difference method: Dry matter 52.5%, crude protein 83.1%, crude fat 51.7%, crude fibre 5.5%, N-free extracts 50.6%. The level of the SBM did not influence the digestibility of the crude nutrients. The apparent digestibility of lysine from SBM depended on the level of intake and was found to be 82.3, 83.4 and 89.0%, resp. There were no differences in the digestibility of other amino acids.

Amino Acids↗
PubMed1989

[The effect of different high levels of soy extract pellets in the ration on the digestibility of crude nutrients, basic and sulfur-containing amino acids of wheat in colostomized laying hybrids].

In two digestibility experiments with 4 colostomized laying hybrids each, the influence of 12.5% (ration 1) and 25% soybean meal (ration 2) on the digestibility of the crude nutrients, the basic and sulphur-containing amino acids in the wheat rations was tested. In ration 1 the digestibility of the crude protein was 84.9%, of the crude fat 56.6% and that of the N-free extractives 87.4%; for ration 2 the values were 83.6%, 47.4% and 82.5%. The digestibility values for wheat acquired with the difference method for ration 1 were 85.7% for crude protein, 57.0% for crude fat and 89.8% for N-free extractives; energy concentration was 766 EFUhens. For wheat supplemented with 25% soybean meal the same digestibility value of the crude protein could be ascertained, the digestibility of the crude fat and the N-free extractives, however, was lower than for ration 1 so that an energy concentration lower by 3.9% was calculated. The possible causes of the influence of the different levels of lysine and thioamino acids on the digestibility of these amino acids of wheat are described.

Amino Acids↗
PubMed1994

[Effect of the convertibility of energy (Q) on energy maintenance requirement and utilization and convertible energy for the assessment of ruminants. 1. Digestibility of energy and nutrients].

The energy metabolism was measured by means of indirect calorimetry in growing bulls with mean live weights of 290-420 kg and in wethers with mean live weights of 40-60 kg. The animals were fed 12 (bulls) and 8 rations (wethers) with high variation in the nutrients composition and with a range of energy metabolizability (q) between 0.74 and 0.47 on 3 steps of nutrition level (deposition, maintenance, underfeeding) as a rule. The energy digestibility of the 12 rations tested in growing bulls on the nutrition level maintenance was measured between 81.9 and 56.4% and that of the 8 rations tested in wethers was measured between 82.6 and 55.6%. On the high and middle nutrition levels the data of energy and nutrients digestibility in growing bulls and wethers were in good agreement, except the significant lower digestibility of crude protein in cattle. On the low nutrition level digestibility of energy, crude protein, crude cellulose and N free residual substances in wethers was 3-5 digestibility units lower than in bulls. The increase of nutrition level by 1 unit lowered the energy digestibility in bulls by 4.2 and the nutrients digestibility about 4-8%-units (0.7 for starch). In sheep the effect was not so high as in cattle. There were differences in the rumen physiological parameters between the animal species. In the growing bulls' rumen liquid the part of acetate was higher and the parts of propionate and butyrate were lower. The content of NH3 was higher in sheep. The increase of nutrition level caused higher amounts of volatile fatty acids in the two animal species with lowering the part of acetic acid and raising the parts of propionic and butyric acid.

Animal Feed↗
PubMed1996

[The effect of starch-rich single feed on the digestibility and the energy content of corn silage in cattle and sheep].

Different starch components were added to rations with maize silage measuring the influence of the supplements on the digestibility and energy content of maize silage in cattle (n = 36) and sheep (n = 36). The starch-rich components maize, wheat, barley, oat, cassava meal and potato starch were added to the total rations on average of 33%. All supplements were ground (sieve of 2.5 mm); additionally, wheat was added in extruded or crushed form. All rations including the control ration without starch components were supplemented with soybean meal to an average crude protein content of 12.4% DM. The mean starch content of the total rations was 42% DM. The supplementation of maize silage with the different starch components increased the digestibility of the organic matter of all rations on average only slightly from 77% to 78% in cattle, while the mean digestibility in sheep raised from 74% to 79% more pronounced. However, the influence of the different starch components on the digestibility was similar for both ruminants. The supplementation with the ground, crushed or extruded wheat, with barley and with oats impaired the digestibility of the crude fibre of the total ration and of the maize silage, respectively. Therefore, the digestibility of the organic matter of maize silage was reduced and the energy content decreased by about 6% in comparison to the control ration without starch supplementation. However, the supplementation with maize, cassava meal or potato starch had no negative effects on the digestibility and energy content of maize silage.

Animal Feed↗
PubMedDate not supplied

Cardiorespiratory effects of forced activity and digestion in toads.

Digestion and physical activity are associated with large and sometimes opposite changes in several physiological parameters. Gastric acid secretion during digestion causes increased levels of plasma bicarbonate ([HCO-3](pl)), whereas activity leads to a metabolic acidosis with increased lactate and decrease in plasma bicarbonate. Here we describe the combined effects of feeding and activity in the toad Bufo marinus to investigate whether the increased bicarbonate buffering capacity during digestion (the so-called alkaline tide) protects the acid-base disturbance during activity and enhances the subsequent recovery. In addition, we describe the changes in arterial oxygen levels and plasma ion composition, as well as rates of gas exchange, heart rates, and blood pressures. Toads were equipped with catheters in the femoral artery and divided into four experimental regimes: control, digestion, forced activity, and forced activity during the postprandial period (N=6 in each). Digestion induced a significant metabolic alkalosis with increased [HCO-3](pl) that was completely balanced by a respiratory acidosis; that is, increased arterial Pco(2) (P(a)co(2)), so that arterial pH (pH(a)) did not change. Forced activity led to a substantial reduction in pH(a) by 0.43 units, an increase in plasma lactate concentration by 12.5 mmol L(-1), and a reduction in [HCO-3](pl) of similar magnitude. While digesting animals had higher P(a)co(2) and [HCO-3](pl) at rest, the magnitude and duration of the changes in arterial acid-base parameters were similar to those of fasting animals, although the reduction in pH(a) was somewhat lower (0.32 units). In conclusion, while recovery from the acidosis following exercise did not seem to be affected by digestion, the alkaline tide did slightly dampen the reduction in pH(a) during activity.

Acid-Base Equilibrium↗
PubMed1988

Solubility of inorganic iron as affected by proteolytic digestion.

The effects of enzymatic digestion on the iron-solubilizing properties of chicken muscle were examined. A water-soluble extract, an acid-soluble extract, and an acid-insoluble fraction were subjected to a simulated gastrointestinal digestion using pancreatin and/or pepsin: The solubility of added Fe was significantly affected only by the acid-insoluble fraction and increased linearly as pepsin digestion progressed from 0 to 4 h. A maximum was reached when this treatment was followed by a 1-h pancreatin digestion. Pepsin digestion products with molecular weight (MW) less than 10,000 solubilized significantly more Fe than those with MW greater than or equal to 10,000. In contrast pancreatin digestion products of MW less than 10,000 were not effective Fe-solubilizing agents. The influence of chicken breast muscle on added Fe solubility appears to be related to the production of digestion intermediates that can act as ligands in the formation of soluble Fe complexes.

Animals↗