Fiber-rich Diet Research Articles

Influence of Dietary Fiber on the Development of the Gastrointestinal Tract and the Performance of Gilts

Optimal intestinal development in gilts is a prerequisite for a better farrowing and a higher feed intake in lactation, and these are important facets in improving animal welfare for sows in a high-performance situation. The present study aimed to evaluate the effects of a fiber-rich diet on these topics. Studies with 20 male Topigs castrates and a performance study with 38 female siblings were conducted. Pigs in both of the groups were offered either a control diet (CG) or a high fiber diet (FG) during the second half of the rearing phase (~97 kg BW) until 7 days a.p. At the time of the insemination of the gilts (body weight >170 kg), the castrates were slaughtered and the morphological parameters of the gastrointestinal tract were taken. In the performance study, the feed intake as well as the number and weight of the live and stillborn piglets and the weaning weight of the litters were recorded. The results indicated that the high fiber diet with a greater swelling capacity was beneficial to the development of the gastrointestinal tract (stomach weight CG = 714 g, FG = 812 g, p = 0.007), increased the litter weight (CG =15.9 kg, FG = 20.6 kg, p = 0.045) and resulted in a higher feed intake during lactation overall (CG = 196 kg, FG = 211 kg, p = 0.035).

Effects of Auricularia auricula and its polysaccharide on diet-induced hyperlipidemia rats by modulating gut microbiota

Abstract It is well known that Auricularia auricula (A. auricula) and Auricularia auricula polysaccharide (AAP) have anti-hyperlipidemia effects, but their mechanism and the relationship with the gut microbiota structure of the subjects were barely reported. In this study we found that A. auricula intervention could reduce the levels of total cholesterol and low-density lipoprotein cholesterol of hyperlipidemia rats by 44.03% and 66.21%, while AAP intervention by 31.38% and 41.38%, respectively. High-throughput sequencing analysis further indicated that A. auricula and AAP interventions could modulate gut microbiota structure. While, the difference was that A. auricula upregulated the high-abundance SCFA-producing genus Bacteroides and Paraprevotella related to dietary fiber-rich diet, while AAP could better enrich several lower-abundance SCFA-producing bacteria such as Flavonifractor and Clostridium IV. The results implied that the different anti-hyperlipidemia effects of A. auricula and AAP interventions might have a potential link with the diverging modulation of gut microbiota structure.

Dietary Fibre May Mitigate Sarcopenia Risk: Findings from the NU-AGE Cohort of Older European Adults.

Sarcopenia is characterised by a progressive loss of skeletal muscle mass and physical function as well as related metabolic disturbances. While fibre-rich diets can influence metabolic health outcomes, the impact on skeletal muscle mass and function is yet to be determined, and the moderating effects by physical activity (PA) need to be considered. The aim of the present study was to examine links between fibre intake, skeletal muscle mass and physical function in a cohort of older adults from the NU-AGE study. In 981 older adults (71 ± 4 years, 58% female), physical function was assessed using the short-physical performance battery test and handgrip strength. Skeletal muscle mass index (SMI) was derived using dual-energy X-ray absorptiometry (DXA). Dietary fibre intake (FI) was assessed by 7-day food record and PA was objectively determined by accelerometery. General linear models accounting for covariates including PA level, protein intake and metabolic syndrome (MetS) were used. Women above the median FI had significantly higher SMI compared to those below, which remained in fully adjusted models (24.7 ± 0.2% vs. 24.2 ± 0.1%, p = 0.011, η2p = 0.012). In men, the same association was only evident in those without MetS (above median FI: 32.4 ± 0.3% vs. below median FI: 31.3 ± 0.3%, p = 0.005, η2p = 0.035). There was no significant impact of FI on physical function outcomes. The findings from this study suggest a beneficial impact of FI on skeletal muscle mass in older adults. Importantly, this impact is independent of adherence to guidelines for protein intake and PA, which further strengthens the potential role of dietary fibre in preventing sarcopenia. Further experimental work is warranted in order to elucidate the mechanisms underpinning the action of dietary fibre on the regulation of muscle mass.

Validation of a New Resource-Efficient Feeding System for Fattening Pigs Using Increased Crude Fiber Concentrations in Diets: Feed Intake and Ammonia Emissions.

Simple SummaryThe feeding of fattening pigs and its associated ammonia emissions are current core problems in social debate that affects climate change and sustainability. Feeding methods offer great potential to increase animal welfare and sustainability, and negative impacts on the environment can be reduced. Fattening pigs differ in their performance potential and in their nutrient requirements. A high feed intake capacity can lead to luxury consumption. Diets rich in crude fiber should prevent excess feed intake and cause better nitrogen fixation by microorganisms in the animals’ large intestines. In a pig fattening farm, it was investigated whether and how diets rich in crude fiber can influence feed intake and ammonia emissions. The animals were divided into feeding groups according to their presumed performance potential by ultrasound examinations. Therein, body compositions were evaluated, and feed intake capacity and body weight were automatically recorded. The aim of the study was to enable adapted feeding of the animals by regarding their individual differences in body composition and performance potential. Roughage-based diets had significant influence on feed intake and did not increase ammonia emissions. Based on the results of this study a performance-based control of the feed intake should be made possible.The housing of fattening pigs, their feeding, and the emissions associated with this process are subjects of criticism. In order to reduce emissions and ensure resource efficiency, new paths must be taken; animals must be fed closer to their actual needs. In a pig fattening farm, 655 animals were grouped according their body weight and their body composition, consisting of weight and muscle-fat-ratio, which was determined by ultrasound examinations. The influence of different concentrations of triticale whole plant silage (WPS) (from 2.5% to 10%) on the feed intake capacity (3.88 kg to 2.71 kg (88% dry matter (DM))) of each group and the ability to control it was determined. Ammonia emissions were measured and the pens floor pollution was assessed. The animals could be distinguished significantly from each other by ultrasound examinations. The crude fiber influenced the level of daily feed intake. Ammonia emissions were not negatively influenced and could be partly reduced. There was no negative impact on surface contamination due to the increased use of crude fiber. The amount of daily feed intake was controlled by crude fiber rich diets. If these findings are adapted to certain types of pigs, a reduction of emissions and an increased resource efficiency can be expected.

High fibre selection by roe deer (Capreolus capreolus): evidence of ruminal microbiome adaption to seasonal and geographical differences in nutrient composition

Context. The European roe deer owes its ability to digest fibre to its microbiome. This is made up of many different species at different levels of abundance and with different differentiations. In Europe, the roe deer is often classified as a so-called ‘concentrate selector’. This term has often been interpreted by different researchers to mean a selector of either protein- or energy-rich food. According to various studies, this selection behaviour is due to the low abundance of fibre-degrading microorganisms. Aims. The aim of the present study was to determine the concentration of crude nutrients in the rumen of roe deer, with the focus on the fibre fractions, and to show changes among seasons and between habitats. Furthermore, the aim was to find out how far the composition of the ruminal microbiota adapts to these changes. Methods. From 2011 to 2014, we collected the rumens of 245 roe deer in two Bavarian habitat types, a forest and an agricultural habitat. The crude nutrient contents and the size of the total microbiome and the proportions of individual genera were determined in the rumen content. Key results. The average annual concentration of crude fibre in the ingested food is 26–30% and this rises to 38% in certain months. The forest roe deer had the highest proportions of crude fibre in their food and the concentrations of other nutrients were also highly dependent on the season and habitat. Furthermore, the animals also have far less protein in their rumen content than often assumed. The total number of microorganisms in the rumens of the forest deer is significantly higher than in animals living in the agricultural area. The number of microorganisms was highest in the forest roe deer in winter, and in the roe deer from the agricultural area in summer. Clear connections can also be seen between individual groups of microorganisms and particular crude nutrients. The high crude-fibre concentration leads to a high number of fibre-degrading microorganisms, such as, for example, anaerobic fungi or the Ruminococcus flavefaciens. Conclusions. The results showed a high adaptability of the animals to a fibre-rich diet. The microbiome adapts very well to the respective nutrient availabilities. This, in turn, is what allows the roe deer to adapt so readily to diverse habitats and environmental conditions. Implications. Due to the generally high concentrations of fibre, combined with the high numbers of fibre-degraders in the rumen, we suggest that, from now on, we should talk of a roe deer as being a ‘selector’ or ‘browser’ rather than a ‘concentrate selector’.

Potential Correlation between Dietary Fiber-Suppressed Microbial Conversion of Choline to Trimethylamine and Formation of Methylglyoxal.

Dietary interventions alter the formation of the disease-associated metabolite, trimethylamine (TMA), via intestinal microbial TMA lyase activity. Nevertheless, the mechanisms regulating microbial enzyme production are still unclear. Sequencing of the gut bacteria 16S rDNA demonstrated that dietary intervention changed the composition of the gut microbiota and the functional metagenome involved in the choline utilization pathway. Characterization of the functional profile of the metagenomes and metabonomics analysis revealed that a series of Kyoto Encyclopedia of Genes and Genomes orthologous groups and enzyme groups related to accumulation of methylglyoxal (MG) and glycine were enriched in red meat diet-fed animals, whereas fiber-rich diet suppressed glycine formation via the MG-dependent pathway. Our observations suggest associations between choline-TMA lyase expression and MG formation, which are indicative of a novel role of the gut microbiota in choline metabolism and highlight it as a potential target for inhibiting TMA production.

The Strange Case of Prevotella copri: Dr. Jekyll or Mr. Hyde?

This issue of Cell Host & Microbe highlights the opposite faces of Prevotella copri (P.copri). Tett etal. (2019) and Fehlner-Peach etal. (2019) unravel the complexity of gut dwelling P.copri, whereas Rolhion etal. (2019) explore the P.copri dark side with its ability to potentiate Listeria monocytogenes pathogenicity.

Influences of environment on the development and lifetime reproductive performance in domestic rabbit females

<p class="MDPI18keywords">Environmental insults of different nature and intensity, such as fluctuation in the air temperature, which can affect access to food, its quality and diseases, are a reality in any livestock system. This is much more important when the insults occur in early life, conditioning the development and adult life of animals. In ecology, for instance, it is widely accepted that high quality offspring are more reactive against predators, occupy better territories and find more mates, resulting in longer lives and greater fitness. It is also a given that adults exposed to famine or disease as juveniles have shorter lives and produce fewer offspring. To determine whether the environment influences the development and lifetime reproductive performance of rabbit females, we designed an experiment combining two factors: nest and pubescent development. Nest development was measured by recording the average daily gain of 864 females during suckling and during their pubescent life (63 to 184 d old), and body development was conditioned by providing animals a high-energy control (C) or a fibre-rich (F) diet. However, in the course of the study, 191 of the 864 pubescent females were exposed to rabbit haemorrhagic disease (RHD). This unexpected environmental insult was considered as a third experimental factor influencing the reproductive performance of rabbit females. Contrary to expectation, fast suckling gain impairs reproductive lifespan, resulting in fewer newborn kits produced in a female lifetime. Although females on diet F lived 37 d longer than females on diet C, this difference was only perceived in their pubescent life. In addition, the exposure to RHD interacted with suckling gain (SG). Exposed females with a fast SG produced more kits as adults, but in the absence of the virus, high SG females produced fewer newborn kits. These results open new insights into the management of future breeders during nesting and pubescent life.</p>

Impact of a Nomadic Pastoral Lifestyle on the Gut Microbiome in the Fulani Living in Nigeria.

The co-evolution of the gut microbiota with its human host has revolutionized our current scientific viewpoint about the contribution of diet and lifestyle on human health. Most studies so far have focused on populations living in the United States and Europe or compared those with communities from other geographic areas in the world. In order to determine the taxonomic and predicted functional profile of the gut microbiome of a hitherto unstudied human community, we investigated the phylogenetic diversity of the gut microbiota in a community of Fulani nomadic pastoralists, and their semi-urbanized neighbors – the Jarawa. The Jarawa reside in a city (Jos) in the north-central part of Nigeria, and are adapted in part to a westernized lifestyle. The nomadic Fulani lifestyle resembles a mix of Paleolithic and Neolithic lifestyle patterns with a greater predisposition to diseases. The fecal microbiota of the Fulani and the Jarawa were characterized by paired-end Illumina MiSeq sequencing of the 16S rRNA gene, followed by downstream bioinformatics analysis of the sequence reads. The Fulani harbored increased numbers of signatures of microbes that are known to be associated with a foraging lifestyle such as the Bacteroidetes, Spirochaetes, and Prevotellaceae, while the Jarawa were dominated by signatures of Firmicutes, Ruminococcaceae, Lachnospiraceae, and Christensenellaceae. Notably, the gut microbiota of the Fulani showed less taxonomic diversity than those of the Jarawa. Although they reside in the same geographical zone, microbial community composition was significantly different between the two groups. Pathogens were predicted to be more abundant in the gut microbiota of the Fulani than of the Jarawa. Predicted pathogenic pathways and pathways associated with the breakdown of fiber-rich diet were enriched in the Fulani, including glutathione metabolism, while pathways associated with the consumption of low-fiber diet and xenobiotics, including fructose and mannose metabolic pathways, and nitrotoluene degradation pathways, respectively, were enriched in the Jarawa. Significant differences in composition between both groups were likely due to differences in diet and lifestyle and exposure to pathogens. These results suggest that microbial diversity may not always be higher in non-industrialized societies than in westernized societies, as previously assumed.

Effects of dietary fibre level and body weight of pigs on nutrient digestibility and available energy in high-fibre diet based on wheat bran or sunflower meal.

The objectives of this study were (a) to investigate the effect of body weight (BW) on available energy in fibre-rich diets containing two NDF levels; and (b) to evaluate the effect of fibre type and NDF level on AA digestibility. In Exp. 1, barrows (24 at 33.4±1.1kg; 24 at 86.8±3.3kg) were randomly allotted to 4 diets containing a high protein basal (HPB), a low protein basal (LPB), 70% HPB+30% wheat bran (WB) (HPB-WB) and 70% LPB+30% sunflower meal (SFM) (LPB-SFM). In Exp. 2, barrows (24 at 33.5±1.8kg; 24 at 87.0±3.8kg) were randomly allotted to 4 diets containing no SFM with 12% NDF (SFM0LF), no SFM with 16% NDF (SFM0HF), 24% SFM with 12% NDF (SFM24LF) and 24% SFM with 16% NDF (SFM24HF). In Exp. 3, twelve barrows (35.5±3.4kg) fitted with T-cannulas were allotted to two 6×4 Youden square design with 6 diets (4 same diets as in Exp. 2 and 2 nitrogen-free diets). The concentration of DE, ME and ATTD of GE, CP, NDF and ADF in diets was greater (p<.01) when fed to 90kg pigs compared with 30kg pigs. The ME in ingredients was not affected by BW. The ATTD of NDF was negatively correlated with the CF (r=-.98; p<.01), ADF (r=-.99; p<.01) and ADL content (r=-.96; p<.01). The ME of diets was negatively correlated with the ATTD of CF (r=-.98; p<.01). The addition of SFM increased the standardized ileal digestibility (SID) of Met (p<.05). In conclusion, diets rich in fibre had different nutritional values at different pig weight stages. The AA digestibility depends mainly on chemical composition of diets.

Pregnant women have inadequate fiber intake while consuming fiber-rich diets in low-income rural setting: Evidences from Analysis of common "ready-to-eat" stable foods.

The intake of fiber‐rich foods during pregnancy has several health benefits to the pregnant woman including lowering the risks of diabetes, preeclampsia, and constipation. However, little is known about the content, daily intake levels, and adequacy of fiber among pregnant women in many low‐income settings. We aimed to identify common food items and determine adequacy of dietary fiber intake levels among pregnant women in rural Ethiopia. Dietary data were collected from a subsample (n = 55) of pregnant women enrolled to a larger prospective cohort study (n = 414). Dietary intake level was measured using repeated 24‐hr dietary recall method and weighing the total amount of daily food. Fiber content was determined using the Weende method supplemented by other sources.The mean [±SD] dietary fiber intake level was 25.89 [±5.09 mg/g] per day, which declined across pregnancy trimester from 26.01 [±9.18 mg/g] to 22.67 [±9.01 mg/g] and 24.56 [±9.98 mg/g] during the first, to second and third pregnancy trimesters, respectively. Boiled cereals and coffee contributed to nearly two‐thirds (63.2%) of the daily fiber intake, while the major bulk of daily food, enjera, contributed to less than a quarter (24.3%) of the fiber intake. Though dietary patterns favor diversified intake for fiber, the mean intake levels below the recommended levels and proportion of women getting adequate to the physiologic stages of pregnancy were inadequate compared to the standard. Mothers, in such community, could benefit from increasing overall intake of existing food to satisfy their fiber needs during pregnancy.

MiRNA-Gene Regulatory Network in Gnotobiotic Mice Stimulated by Dysbiotic Gut Microbiota Transplanted From a Genetically Obese Child.

Gut microbiota (GM) dysbiosis has been considered a pathogenic origin of many chronic diseases. In our previous trial, a shift in GM structure caused by a complex fiber-rich diet was associated with the health improvement of obese Prader-Willi syndrome (PWS) children. The pre- and post-intervention GMs (pre- and post-group, respectively) from one child were then transplanted into gnotobiotic mice, which resulted in significantly different physiological phenotypes, each of which was similar to the phenotype of the corresponding GM donor. This study was designed to investigate the miRNA-gene regulatory networks involved in causing these phenotypic differences. Using the post-group as a reference, we systematically identified and annotated the differentially expressed (DE) miRNAs and genes in the colon and liver of the pre-group in the second and fourth weeks after GM inoculation. Most of the significantly enriched GO terms and KEGG pathways were observed in the liver and were in the second week after GM transplantation. We screened 23 key genes along with their 73 miRNA regulators relevant to the host phenotype changes and constructed a network. The network contained 92 miRNA-gene regulation relationships, 51 of which were positive, and 41 of which were negative. Both the colon and liver had upregulated pro-inflammatory genes, and genes involved in fatty acid oxidation, lipolysis, and plasma cholesterol clearance were downregulated in only the liver. These changes were consistent with lipid and cholesterol accumulation in the host and with a high inflammation level. In addition, the colon showed an impacted glucagon-like peptide 1 (GLP-1) signaling pathway, while the liver displayed decreased insulin receptor signaling pathway activity. These molecular changes were mainly found in the second week, 2 weeks before changes in body fat occurred. This time lag indicated that GM dysbiosis might initially induce cholesterol and lipid metabolism-related miRNA and gene expression disorder and then lead to lipid accumulation and obesity development, which implicates a causative role of GM dysbiosis in obesity development rather than a result of obesity. This study provides fundamental molecular information that elucidates how dysbiotic GM increases host inflammation and disturbs host lipid and glucose metabolism.

Effects of dietary fiber content and different fiber-rich ingredients on endogenous loss of fat and fatty acids in growing pigs

Effects of dietary fiber content and different fiber-rich ingredients on endogenous loss of fat and fatty acids in growing pigs

Contribution of nutrient fluxes to the evolution of the net energy systems, example of the INRA feeding system for beef cattle.

Energy feeding systems define energy as a whole, but progress made to define metabolizable energy (ME) as the sum of the metabolizable nutrients produced by digestion and available for tissue metabolism in a wide range of nutritional situations opens the way to quantitatively model and predict nutrient fluxes between and within tissues and organs and improve predictions of energy use. This review addresses the contribution of nutrient flux concepts and data to the evolution of the Institut de la Recherche Agronomique (INRA) energy feeding system for growing and fattening cattle and evaluates the outcomes on the net energy (NE) requirements. It summarizes recent progress made to quantitatively predict nutrient fluxes both at digestive and visceral levels. It reviews how nutrient flux concepts and results were introduced in the recently updated INRA feeding system, resulting in improvements in the accuracy of the revised digestible energy (DE) and ME value of diets. The use of an independent database showed that for diets fed to fattening cattle, DE and ME concentrations were downgraded for low-energy-dense diets and upgraded for high-energy-dense diets. We are also showing that compared with its previous version, the updated INRA system improves the quantitative relationship between ME supply and flows of metabolizable nutrients. Evidence is provided on how measured nutrient fluxes at portal level were used to evaluate the predicted flows of metabolizable nutrients. This review then revisits the NE values of diets for fattening cattle as defined by the INRA feeding system and not updated yet. Using an independent database and at similar ME intake, carcass composition was shown to be linearly related to the energy density of diets for fiber-rich diets but not for concentrate-rich diets, suggesting that the efficiency of energy utilization of ME into NE is not linearly related to differences in the composition of the gain. Accounting for the balance of metabolizable nutrients or their proxies in models used to predict carcass composition from ME intake can improve predictions. Overall partitioning aggregated energy fluxes into their subcomponent nutrient fluxes in a more physiological approach offers promising perspectives for the evolution of NE feeding systems.

Improving the physicochemical properties of partially enhanced soluble dietary fiber through innovative techniques: A coherent review

Plant-based foods have a considerable quantity of bioactive moieties which provide nutritional benefits. Literature demonstrated that intake of a dietary fiber-rich diet has positive impacts on human health. Moreover, several studies have indicated that a high intake of soluble dietary fiber is associated with a reduced risk of numerous chronic aberrations as compared to insoluble dietary fiber. For the purpose, special attention has been paid toward enhancement of soluble dietary fiber in foods through different innovative techniques. In this review, efforts are directed to elaborate the importance of dietary fiber and to highlight the significance of conversion of insoluble dietary fiber into soluble dietary fiber. Soluble dietary fiber are functionally and nutritionally more important than insoluble dietary fiber. Moreover, much has been focused on the solubilization of dietary fibers through different techniques that ameliorates the quantity of soluble dietary fiber. An array of different techniques and methods are used such as mechanical degradation, extrusion cooking, thermal processes, chemical treatment, enzymatic methods, microbiological fermentation, and some other processes. Furthermore, physicochemical and functional perspectives of soluble dietary fiber are also the limelight of the article. Practical applications The current study is aimed to overview the functional importance and modification of dietary fiber through different techniques. Owing to water solubility, soluble dietary fibers are more important than insoluble dietary fiber in terms of gastrointestinal role, cholesterol lowering effect, weight management, improved immunity, and mood enhancement and have a positive role in product development. Therefore, modification is much important for an industrial and health point of view as it generates physicochemical changes in dietary fiber which improve bioactive functionality. As good source of soluble dietary fiber, treated foods, especially cereals, can be incorporated in products/baking products to make these functional against various diseases because consumers are more conscious toward their diet and wish for natural remedies.

Distinct Genetic and Functional Traits of Human Intestinal Prevotella copri Strains Are Associated with Different Habitual Diets

The role of intestinal Prevotella species in human health is controversial, with both positive and negative associations. Strain-level diversity may contribute to discrepancies in genus and species associations with health and disease. We dissected the gut metagenomes of Italians with varying dietary habits, investigating the presence of distinct Prevotella copri strains. Fiber-rich diets were linked to P.copri types with enhanced potential for carbohydrate catabolism. P.copri strains associated with an omnivore diet had ahigher prevalence of the leuB gene-involved in branched-chain amino acid biosynthesis-a risk factor for glucose intolerance and type 2 diabetes. These P.copri pangenomes were compared to existing cohorts, providing evidence of distinct gene repertoires characterizing different P.copri populations, with drug metabolism and complex carbohydrate degradation significantly associated with Western and non-Western individuals, respectively. Strain-level P.copri diversity in gut microbiomes is affected by diet and should be considered when examining host-microbe associations.

Reduced-Particle-Size Wheat Bran Is Efficiently Colonized by a Lactic Acid-Producing Community and Reduces Levels of Enterobacteriaceae in the Cecal Microbiota of Broilers.

In the present study, we investigated whether reducing the particle size of wheat bran affects the colonizing microbial community using batch fermentations with cecal inocula from seven different chickens. We also investigated the effect of in-feed administration of regular wheat bran (WB; 1,690 μm) and wheat bran with reduced particle size (WB280; 280 μm) on the cecal microbial community composition of broilers. During batch fermentation, WB280 was colonized by a lactic acid-producing community (Bifidobacteriaceae and Lactobacillaceae) and by Lachnospiraceae that contain lactic acid-consuming butyric acid-producing species. The relative abundances of the Enterobacteriaceae decreased in the particle-associated communities for both WB and WB280 compared to that of the control. In addition, the community attached to wheat bran was enriched in xylan-degrading bacteria. When administered as a feed additive to broilers, WB280 significantly increased the richness of the cecal microbiota and the abundance of bacteria containing the butyryl-coenzyme A (CoA):acetate CoA-transferase gene, a key gene involved in bacterial butyrate production, while decreasing the abundances of Enterobacteriaceae family members in the ceca. Particle size reduction of wheat bran thus resulted in the colonization of the bran particles by a very specific lactic acid- and butyric acid-producing community and can be used to steer toward beneficial microbial shifts. This can potentially increase the resilience against pathogens and increase animal performance when the reduced-particle-size wheat bran is administered as a feed additive to broilers.IMPORTANCE Prebiotic dietary fibers are known to improve the gastrointestinal health of both humans and animals in many different ways. They can increase the bulking capacity, improve transit times, and, depending on the fiber, even stimulate the growth and activity of resident beneficial bacteria. Wheat bran is a readily available by-product of flour processing and is a highly concentrated source of (in)soluble dietary fiber. The intake of fiber-rich diets has been associated with increased Firmicutes and decreased Proteobacteria numbers. Here, we show that applying only 1% of a relatively simple substrate which was technically modified using relatively simple techniques reduces the concentration of Enterobacteriaceae This could imply that in future intervention studies, one should take the particle size of dietary fibers into account.

Fiber and Nutritional Health

Populations that consume more dietary fiber have less chronic disease. According to the 2002 Dietary Reference Intakes (DRIs), dietary fiber includes carbohydrates and lignin that are intrinsic and intact in plants that are not digested and absorbed in the small intestine. Functional fiber consists of isolated or purified carbohydrates that are not digested and absorbed in the small intestine that confer beneficial physiologic effects in humans. Total fiber is the sum of dietary fiber and functional fiber. Fibers alter laxation, attenuate the rise in blood glucose, and normalize blood cholesterol. The solubility of fibers was originally thought to determine physiologic properties, with soluble fiber linked to cholesterol-lowering properties and insoluble fiber linked to laxation effects. The DRI Committee recommended that other descriptors for fiber be developed, suggesting viscosity and fermentability. Manufacturers are allowed to list total dietary fiber, soluble fiber, and insoluble fiber on the Nutrition Facts panel. DRIs recommend consumption of 14 g of dietary fiber per 1,000 kcal based on epidemiologic studies showing protection against cardiovascular disease. Usual intake of dietary fiber is only 15 g/day. Even with a fiber-rich diet, a supplement may be needed to bring fiber intakes into the recommended range. Dietary messages to increase consumption of high-fiber foods such as whole grains, pulses, fruits, and vegetables should be broadly supported by the medical profession. This review contains 3 Tables and 38 references Key words: constipation, diarrhea, dietary fiber, health claims, laxatives, plant foods, stool weight, transit time

Do bad habits bring a double constipation risk?

Good dietary habits, fluid intake, and regular exercise are considered to ease defecation although very few cases of chronic constipation can be managed through these approaches alone. Good defecation habits are recommended to avoid chronic constipation; however, the literature regarding this remains scarce. In this paper, we aimed to assess the association of bad habits concerning defecation, such as postponing, reluctance, or avoiding defecation anywhere but at home, with chronic constipation. This was a cross-sectional observational study including subjects from a tertiary hospital taskforce. In total, 415 of 910 eligible subjects were randomly selected. A cluster of questionnaires easy to understand and fill out was distributed. The questionnaires included queries regarding demographic data; past medical history; the presence of constipation; and dietary, other lifestyle, and defecation habits. The Rome III criteria for chronic constipation were also recorded. In total, 24.3% of the subjects considered themselves constipated, and 26.5% fulfilled the Rome III criteria for constipation. There were obvious differences in constipation prevalence by sex (men 5% vs. women 31%). Fiber-rich diet, fluid intake, and exercise habits were not related to constipation. Defecation habits significantly correlated with the presence or absence of constipation: regular schedule (OR 0.39; CI 95% 0.23-0.67), persistently postponing defecation (OR 1.94; CI 95% 1.13-3.34), or avoiding defecation anywhere but at home (OR 2.38; CI 95% 1.4-4.1). Compared with dietary habits, behavioral aspects surrounding defecation are more related to chronic constipation. Our results indicate that the modification of these bad habits may be the first step in chronic constipation treatment.

Assessment of fecal near-infrared spectroscopy to predict feces chemical composition and apparent total-tract digestibility of nutrients in pigs.

Apparent total-tract digestibility (ATTD) of nutrients could be an alternative measure of feed efficiency (FE) when breeding for robust animals that are fed fiber-rich diets. Apparent total-tract digestibility of nutrients requires measuring individual feed intake of a large number of animals which is expensive and complex. Alternatively, ATTD of nutrients and feces chemical composition can be predicted using fecal near-infrared reflectance spectroscopy (FNIRS). The objective of this study was to assess if the feces chemical composition and ATTD of nutrients can be predicted using FNIRS that originate from various pig-experimental datasets. Fecal samples together with detailed information on the feces chemical composition and ATTD of nutrients were obtained from four different pig experiments. Feces near-infrared spectroscopy was analyzed from fecal samples of a complete dataset. The model was calibrated using the FNIRS and reference samples of feces chemical composition and ATTD of nutrients. The robustness and predictability of the model were evaluated by the r2 and the closeness between SE of calibration (SEC) and SE of cross-validation (SECV). Prediction of the feces chemical components and ATTD of nutrients were successful as SEC and SECV were equivalent. Calibration model was developed to estimate the ATTD of nutrients and fecal chemical composition from the FNIRS and worked well for OM (r2 = 0.94; SEC = 48.5; SECV = 56.6), CP (r2 = 0.89; SEC = 18.1; SECV = 18.8), GE (r2 = 0.92; SEC = 1.2; SECV = 1.4), NDF (r2 = 0.94; SEC = 55; SECV = 60.2), OM digestibility (r2 = 0.94; SEC = 5.5; SECV = 6.7), GE digestibility (r2 = 0.88; SEC = 2.3; SECV = 2.6), and fat digestibility (r2 = 0.79; SEC = 6, SECV = 6.8). However, the SE of prediction was slightly higher than what has been reported in another study. The prediction of feces chemical composition for fat (r2 = 0.69; SEC = 11.7, SECV = 12.3), CP digestibility (r2 = 0.63; SEC = 2.3; SECV = 2.7), and NDF digestibility (r2 = 0.64, SEC = 7.7, SECV = 8.8) was moderate. We conclude that the FNIRS accurately predicts the chemical composition of feces and ATTD of nutrients for OM, CP, and GE. The approach of FNIRS is a cost-effective method for measuring digestibility and FE in a large-scale pig-breeding programs.