Development Of Gastrointestinal Tract Research Articles

Impact of different dietary fibre sources on production performance, bacterial composition and metabolites in the caecal contents of rabbits.

This study was conducted to investigate the effects of different dietary fibre sources on growth performance, gastrointestinal tract development, caecal fermentation and bacterial composition in the caecal contents of rabbits. A total of 120 35-day-old weaned Minxinan black rabbits were divided into three groups and fed a diet composed of peanut straw powder (Group A), alfalfa powder (Group B) and soybean straw powder (Group C) as the main fibre source. The final body weight and average daily gainin Group B were higher than those in Group C, and the average daily feed intakeand feed conversion ratio in Group A were lower than those in Group C (p < 0.05). The relative weights of the stomach, small intestine and caecum of rabbits in Group C were higher than those in Groups of B and A, and the relative weights of the caecal contents in Group C were lower than those in Groups A or B (p < 0.05). The pH value and propionic acid, butyric acid and valeric acid concentrations in the caecum of Group C were lower than those in the caecum of Groups A orB, and the concentration of acetic acid in the caecum was lower (p < 0.05). The dominant microbes in the caecal contents of Minxinan black rabbits were Firmicutes, Bacteroidetes and Proteobacteria at the phylum level, and the number of species, Chao1 index and ACE index measured was different between the B-C and A-C groups (p < 0.05). Different dietary fibre sources could affect the growth performance, gastrointestinal tract development and intestinal microbiota of rabbits, and the nutritional value of alfalfa powder was better than that of peanut straw and soybean straw.

Effect of in ovo injection of DL-methionine on hatchability, embryo mortality, hatching weight, blood biochemical parameters and gastrointestinal tract development of breeder chicks

The current investigation was conducted to test the potential effects of in ovo feeding of DL-methionine (MET) on hatchability, embryonic mortality, hatching weight, blood biochemical parameters and development of heart and gastrointestinal (GIT) of breeder chick embryos. 224 Rhode Island Red fertile eggs were randomly distributed into seven experimental treatments: untreated egg (control), buffered saline (0.5% NaCl), and five solutions containing increased levels of MET (0.5, 1.0, 1.5, 2.0 and 2.5%) + 0.5% NaCl, being separated into four groups/replicates (each one with 8 eggs), totaling 32 eggs/treatment. All embryos submitted to in ovo injection with MET presented a decrease in the hatchability results and an increase in the results of intermediary embryonic mortality. Chicks hatched from eggs injected with until to 1.0% MET were heavier and presented better development of the heart and GIT, especially important organs and regions for digestion and nutrient absorption. Conclusively, the in ovo feeding using MET showed positive impacts on hatching weight and GIT development of breeder chicks. However, caused negative impacts on hatchability when used at high levels.

L1CAM expression in human gastrointestinal tract development: From tongue to colon-rectum.

L1CAM (L1 cell adhesion molecule) is a member of the L1 family of neural adhesion molecules, involved in the development of multiple organs and tissues, including kidneys, the enteric nervous system, and adrenal glands. The aim of this study was to analyze, at the immunohistochemical level, the expression of L1CAM in the human tongue, parotid glands, and the different segments of the gastrointestinal tract during human development. Immunohistochemical analysis for L1CAM was performed in the human tongue, parotid glands, and in the different segments of the gastrointestinal tract during development, starting from the 8th up to the 32nd week of gestation. Our results were given by the expression of the L1CAM protein in different segments of the gastrointestinal tract during development, starting from the 8th week up to the 32nd week of gestation. L1CAM-reactive cells appeared aggregated in small bodies, irregular in shape, showing L1CAM storage in the cytoplasm. L1CAM expressing bodies were frequently found to be connected one to the next by thin fibers, a finding suggestive of the existence of an L1CAM network inside the developing tissue. Our study confirms that L1CAM is involved in gut development, as well as in tongue and salivary gland development. These findings confirm that the role of L1CAM in fetal development is not restricted to the central nervous system and are necessary for further studies on the role of this molecule in human development.

Feeding graded levels of dried Sea buckthorn (Hippophaes rhamnoides) berries to broiler chickens

AbstractThe aim of this study was to assess the effects of graded levels (0, 3, 6, 9 and 12 g/kg) of dry Sea buckthorn (SB) berries on growth performance, gastrointestinal tract (GIT) development, jejunal histomorphology, bird antioxidant status and caecal short‐chain fatty acid concentration when fed to female Ross 308 broiler chickens. In addition, expression of cytokine biomarker genes in the jejunum was evaluated. The five experimental diets were fed from 7 to 21 days age to 8 pens (two birds in each) following randomisation. Feeding SB did not influence bird growth performance (p &gt; .05). There was a linear decrease in butyric, acetic and valeric acid concentrations in caecal digesta (p &lt; .05) and a decrease (p &lt; .05) in crypt depth. The expression of IFNG and CD40LG responded quadratically (p &lt; .05), peaking at 6–9 g/kg dietary inclusion of SB, respectively. Other studied variables were not affected by dietary SB inclusion (p &gt; .05). Feeding dry SB berries up to 12 g/kg of diet did not improve the zootechnical variables of healthy commercial‐strain broilers in this study.

Dietary inclusion of fermented ginger straw effect on the growth performance, gastrointestinal tract development and caecal fermentation of fattening rabbits

This experiment was conducted to evaluate the effects of dietary inclusion of fermented ginger straw on the growth performance, gastrointestinal tract development and caecal fermentation of fattening rabbits. A total of 160 45-d-old Laiwu black rabbits were randomly divided into 4 groups and fed 0% (Control), 5, 10 or 15% fermented ginger straw in their diet as a replacement for peanut straw powder. The trial lasted for 7 d of adaptation and 43 d for testing. Growth performance was recorded from 52 to 95 d of age (n=5 per treatment with 30 rabbits, 3 males and 3 females per replicate), TTAD of nutrients from 91 to 95 d of age, and gastrointestinal tract development, caecum fermentation and carcass traits were determined at 95 d of age (n=5 per treatment with 10 rabbits, 1 males and 1 females in per replicate).The results showed that the average daily gain and final body weight in the experimental groups (5, 10 and 15% fermented ginger straw) were higher than in the control group (P&lt;0.05). However, the average daily feed intake in the 15% group was higher than in the other groups, while the total tract apparent digestibility of crude protein, ether extract, neutral detergent fibre and acid detergent fibre were lower than in the control group (P&lt;0.05), and the relative weights of the stomach, small intestine and caecum content in the 15% substitution group were higher than those in the control group (P&lt;0.05). In addition, the thickness of the muscle layer in the 15% substitution group was higher than that in the other groups (P&lt;0.05). Moreover, pH and total volatile fatty acids concentration in the caecal content were similar among the 4 groups (P&gt;0.05). The current work shows that fermented ginger straw could be used as roughage material in fattening rabbit production up to a dietary dose of 10%.

β-sitosterol as an alternative to oxytetracycline: Effect on growth performance, feed intake and utilization efficiency and viscera macromorphometry of Cobb 500 broiler chickens

Antibiotics are used to fortify broiler chicken feeds as growth promoters. Chronic antibiotic use pollutes the environment and causes the development of antibiotic resistance. Natural alternatives that mimic the properties of antibiotics, without causing health and environmental challenges are required. β-sitosterol has antimicrobial, antioxidant, digestive and immune system modulating and growth stimulating activities. We evaluated its potential to replace oxytetracycline as a growth-promoter in broiler chicken feeds. Two hundred and forty, one-day-old Cobb 500 broiler chicks were randomly allocated to four diets where β-sitosterol replaced oxytetracycline at 0 mg/kg (control; fortified with 50 mg/kg oxytetracycline), 500 mg/kg, 1000 mg/kg and 1500 mg/kg (w/w) feed and fed for 6 weeks: 2 weeks for each growth phase. Each diet was replicated thrice with 20 chicks per replicate. Initial, weekly and terminal body mass (TBM) and daily feed intake (FI) were measured. Body mass gain (BMG), average daily gain (ADG) and feed conversion ratio were computed. Terminally, the chickens were fasted for 4 h then slaughtered and dressed. Gastrointestinal tract (GIT) and GIT accessory viscera masses and small and large intestine lengths were measured. Dietary fortification with β-sitosterol had similar effects (P > 0.05) to oxytetracycline on the chickens’ TBM, BMG, ADG, FI and utilisation efficiency and GIT organ macromorphometry. In conclusion, β-sitosterol can replace oxytetracycline in Cobb 500 broiler chicken feeds without compromising growth performance, feed intake and utilisation efficiency and GIT organ growth and development.

The role of milk-derived exosomes in the treatment of diseases.

Exosomes (EXOs) are natural nanoparticles of endosome origin that are secreted by a variety of cells in the body. Exosomes have been found in bio-fluids such as urine, saliva, amniotic fluid, and ascites, among others. Milk is the only commercially available biological liquid containing EXOs. Proof that exosomes are essential for cell-to-cell communication is increasingly being reported. Studies have shown that they migrate from the cell of origin to various bioactive substances, including membrane receptors, proteins, mRNAs, microRNAs, and organelles, or they can stimulate target cells directly through interactions with receptors. Because of the presence of specific proteins, lipids, and RNAs, exosomes act in physiological and pathological conditions in vivo. Other salient features of EXOs include their long half-life in the body, no tumorigenesis, low immune response, good biocompatibility, ability to target cells through their surface biomarkers, and capacity to carry macromolecules. EXOs have been introduced to the scientific community as important, efficient, and attractive nanoparticles. They can be extracted from different sources and have the same characteristics as their parents. EXOs present in milk can be separated by size exclusion chromatography, density gradient centrifugation, or (ultra) centrifugation; however, the complex composition of milk that includes casein micelles and milk fat globules makes it necessary to take additional issues into consideration when employing the mentioned techniques with milk. As a rich source of EXOs, milk has unique properties that, in addition to its role as a carrier, promotes its use in treating diseases such as digestive problems, skin ulcers, and cancer, Moreover, EXOs derived from camel milk are reported to reduce the risk of oxidative stress and cancer. Milk-derived exosomes (MDEs) from yak milk improves gastrointestinal tract (GIT) development under hypoxic conditions. Furthermore, yak-MDEs have been suggested to be the best treatment for intestinal epithelial cells (IEC-6 cell line). Because of their availability as well as the non-invasiveness and cost-effectiveness of their preparation, isolates from mammals milk can be excellent resources for studies related to EXOs. These features also make it possible to exploit MDEs in clinical trials. The current study aimed to investigate the therapeutic applications of EXOs isolated from various milk sources.

Effect of Oat Hull as a Source of Insoluble Dietary Fibre on Changes in the Microbial Status of Gastrointestinal Tract in Broiler Chickens.

Simple SummaryThe aim of this study was to determine the effect of the addition of oat hull (0–3%) and high amounts of cereal grains to the diets of broiler chickens in terms of the development of the upper gastrointestinal tract, and individual microbial counts in the crop and ileum, and the effect of dietary fibre fractions on microbial changes from the beak to the ileum. The addition of 3% oat hull increased the weights of the proventriculus and gizzard, thereby improving the gizzard barrier function. The presence of dietary fibre and hemicelluloses in diets increased the total aerobic microbial count and Lactobacillus spp. bulk in the crop. The presence of insoluble dietary fibre in the diet decreased the total aerobic microbial count and increased the E. coli count in the crop. In the ileum, insoluble dietary fibre decreased the E. coli count and soluble dietary fibre decreased the total combined yeast and mould count.This study aimed to determine the effect of the addition of oat hull (0–3%) and high amounts of cereal grains to the diet of broiler chickens in terms of the development of the upper gastrointestinal tract, individual microbial counts in the crop and ileum, and the effect of dietary fibre fractions on microbial changes from the beak to the ileum. In the 28 d trial, 162 one-day-old Hubbard Flex male chickens with an average body weight of 44.5 g were randomly allocated to 27 metabolic cages. The experiment consisted of a randomised, one factorial ANCOVA design composed of a covariate with two ANOVA factorial designs containing nine treatments (3 × 3): three sources of cereal grains (maize, wheat, and barley, with a minimum amount of 500 g · kg−1, each with nine replications) and three levels of oat hull (0, 1, and 3%, each with nine replications). At the end of the study, 81 chickens (9 in each treatment) were slaughtered to determine the weight of the individual organs and characterise the intestinal microbiota. The application of 3% oat hull to the cereal diets increased the weight of the proventriculus and the gizzard (6.3 and 27.3 g, respectively) in comparison to diets without the addition of this structural component (6.0 and 23.7 g). Higher crop counts of total aerobic microbes (6.29 log CFU · g−1) and Lactobacillus spp. (4.05 log CFU · g−1) were observed in diets containing wheat grain compared with maize (4.62 and 3.55 log CFU · g−1, respectively). The main reason for the microorganism’s growth (p < 0.05) was the amount of soluble dietary fibre and hemicelluloses present in the diet: total aerobic microbial count (respectively r = 0.918 and r = 0.816) and Lactobacillus spp. (respectively r = 0.416 and r = 0.442). Barley diets decreased (p < 0.05) E. coli counts in the ileum (2.69 log CFU · g−1) vs. maize and wheat diets (3.41 and 3.45 log CFU · g−1, respectively), mainly due to the increase in the amount of insoluble dietary fibre in the diet (r = −0.462). Reduced total yeast and mould counts in the ileum were also observed (p < 0.05) in connection with the presence of soluble dietary fibre and hemicelluloses in diets (r = −0.397 and −0.398, respectively).

Metagenomic insights into the modulatory effects of kelp powder (Thallus laminariae)-Treated dairy milk on growth performances and physiological lipometabolic processes of kunming mice.

Kelp powder, supplemented with a dairy cow diet, effectively improved the milk polyunsaturated fatty acids (PUFAs) content. However, little information exists on the downstream effects of the kelp-treated milk on body health, gut microbiota, and nutrient metabolism. For this purpose, 48 3-week old Kunming (KM) male mice with an average body weight of 16.1 g ± 0.2 g were randomly divided into the control treatment (CON, fed with standard chow), the common milk supplement treatment (Milk), and the kelp powder-treated milk supplement treatment (KPM). The experiment lasted for 35 days, with a 7-day long adaptive period and a 28-day long main trial. Phenotypic parameters including growth performances and serum lipids-related parameters were first measured, and results indicated that Milk and KPM supplement significantly promoted the total body weight gain (P < 0.05), while significantly decreasing the feed conversion ratio compared with CON (P < 0.05). No significant differences were observed in the blood lipids content among all three treatments, however, the triglyceride content showed a decreasing trend after KPM supplement treatment. Further, activities of liver lipometabolic-related enzymes were investigated to determine the underlying factors that impacted physiological lipid metabolism. KPM treatment showed a significant reductive effect on the activity of lipogenesis-related enzymes, such as FAS and ACC, while a significant stimulative effect on the activity of lipolysis-related enzymes included the ATGL and CPT1 compared with CON (P < 0.05). Finally, gastrointestinal tract development and cecal microbiota community that correlated with body lipid degradation and absorption were measured to determine the underlying mechanism of KPM supplementation on physiological lipid metabolism. Results indicated that supplementation with KPM significantly enhanced cecal bacteria diversity which was reflected in the significant increase of Chao1 and ACE indexes. Besides, starch-degraded bacteria such as Faecalibacterium, Ruminococcaceae, and Streptococcus are significant decreased (P < 0.05), while cellulose-degraded bacteria including Parabacteroides, Prevotella, Lactobacillus, Clostridium, and Bifidobacterium are significantly increased (P < 0.05) after KPM supplement, which may further restrict the energy generation and therefore reduce the lipid deposition. In summary, kelp supplement helped increase the milk PUFAs content, enhance the bacterial diversity and relative abundances of probiotics, which finally modulated physiological lipid metabolism, and promote growth performances.

In ovo feeding of creatine monohydrate increases performances of hatching and development in breeder chicks

The current investigation was conducted to test the potential effects of in ovo feeding of creatine monohydrate (CMH) on hatchability, embryonic mortality, hatching weight, and development of heart and gastrointestinal tract (main organs and regions) of breeder chick embryos. Rhode Island Red fertile eggs were randomly distributed into seven experimental treatments: untreated egg (control), a sterile buffered solution (0.50% NaCl), and five solutions containing increased levels of CMH (0.50, 1.00, 1.50, and 2.00%) + 0.50% NaCl, being separated in four groups/replicates (three with 15 eggs and one with 16 eggs), totaling 61 eggs/treatment and a total of 427 fertile eggs used. All-in ovo injected groups with CMH decreased the hatchability and increased the intermediary embryonic mortality. At hatching, all-in ovo injected groups with CMH also increased the hatching weight and stimulated the development of the heart and the total length of the gastrointestinal tract, especially important organs for digestion of nutrients (yolk sac, pro-ventricle and gizzard) and regions for nutrient absorption (jejunum + ileum and colon + rectum). Conclusively, the in ovo feeding using CMH showed positive impacts on hatching weight and the development of gastrointestinal tract of chicks. However, caused negative impacts on hatchability.

Effects of dietary inclusion of Xanthoceras sorbifolia Bunge leaves on growth performance, gastrointestinal development, digestive function and gut microbial flora of rabbits

This study aimed to investigate the effects of dietary inclusion of Xanthoceras sorbifolia Bunge (X sorbifolia) leaves (XSL) or solid-state fermented X sorbifolia leaves (FXSL) on the growth performance, gastrointestinal tract development, serum metabolites, intestinal mucosa morphology, cecal fermentation and microflora enumeration of rabbits. A total of 192 healthy New Zealand White male rabbits weighing (940 ± 11 g) were randomly allocated to 3 dietary treatments, with 8 replicates of 8 rabbits each and designated as control, XSL, and FXSL groups. The rabbits in the XSL and FXSL groups were fed diets containing 150 g/kg XSL and FXSL in the basal diets to replace the same level of alfalfa hay, respectively for 42 days. Compared with the control or XSL group, the FXSL rabbits showed increased average daily weight gain (P < 0.05) and final body weight, as well as a decreased feed to gain ratio (P < 0.05). They had increased small intestine weight, small intestine relative weight (P < 0.05), cecum weight, cecum relative weight, and decreased urea nitrogen (UN) content (P < 0.05). Rabbits in the XSL and FXSL groups had lower serum alanine aminotransferase (ALT) (P < 0.05) and aspartate aminotransferase (AST) activities, as well as higher serum alkaline phosphatase (AKP) activity (P < 0.05). Compared to the other two groups, the total volatile fatty acids, the ratio of acetic acid, as well as Lactobacilli and Bifidobacterium populations in the cecal content was increased (P < 0.05) in the FXSL group, while the cecal pH, NH3-N, the ratio of butyric acid, Escherichia coli as well as Clostridium perfringens populations were decreased (P < 0.05). Further, the rabbits from the FXSL group showed higher (P < 0.05) villus height (VH) and VH/crypt depth (CD) both in the jejunum and duodenum. In conclusion, adding 150 g/kg XSL to the diet can replace the same amount of alfalfa powder, simultaneously, adding 150 g/kg FXSL can improve the growth and gastrointestinal tract development, as well as the cecal environment and microbiota balance.

CellDrift: inferring perturbation responses in temporally sampled single-cell data.

Cells and tissues respond to perturbations in multiple ways that can be sensitively reflected in the alterations of gene expression. Current approaches to finding and quantifying the effects of perturbations on cell-level responses over time disregard the temporal consistency of identifiable gene programs. To leverage the occurrence of these patterns for perturbation analyses, we developed CellDrift (https://github.com/KANG-BIOINFO/CellDrift), a generalized linear model-based functional data analysis method that is capable of identifying covarying temporal patterns of various cell types in response to perturbations. As compared to several other approaches, CellDrift demonstrated superior performance in the identification of temporally varied perturbation patterns and the ability to impute missing time points. We applied CellDrift to multiple longitudinal datasets, including COVID-19 disease progression and gastrointestinal tract development, and demonstrated its ability to identify specific gene programs associated with sequential biological processes, trajectories and outcomes.

Effect of beak trimming at hatch and the inclusion of oat hulls in the diet on growth performance, feed preference, exploratory pecking behavior, and gastrointestinal tract traits of brown-egg pullets from hatch to 15 weeks of age

The influence of infrared beak trimming at hatch (IRBT) and the inclusion of oat hulls (OH) in the diet on growth performance, feed preference, exploratory pecking behavior, and gastrointestinal tract (GIT) development, was studied in brown-egg pullets from 0 to 15 wk of age. The experimental design was completely randomized with 4 treatments arranged as a 2 × 2 factorial with IRBT (sham vs. treated) and OH inclusion (0 vs. 3%) as main effects. Each treatment was replicated 20 times and the experimental unit was a cage with 10 pullets. Feed intake (FI), BW gain, feed conversion ratio (FCR), energy intake (EI, kcal AMEn/d), and energy conversion ratio (ECR, kcal AMEn/g of BW gain) were determined by feeding period (0 to 6, 7 to 10, and 11 to 15 wk of age) and cumulatively. Particle size preference was measured at 7 wk and exploratory pecking behavior of the pullets and at 8 to 14 wk of age. From 0 to 6 wk of age, beak trimming decreased FI (P < 0.01) and increased pullet mortality (P < 0.001) but did not affect BW gain. From 0 to 15 wk of age, OH inclusion improved BW uniformity (P = 0.090) but impaired FCR (P < 0.05) without showing any effect on BW gain or ECR. Preference for coarse particles was greater for the sham than for the treated pullets. Beak trimming and OH feeding reduced (P < 0.05) the exploratory pecking behavior of the pullets from 8 to 12 wk of age but not thereafter. Oat hulls increased the relative weights of the full gizzard and intestines at all ages (P < 0.05). In summary, beak trimming did not affect pullet performance at 15 wk of age or GIT development at any age. Oat hulls improved GIT development at all ages but did not affect BW or ECR. Both beak treatment and OH inclusion affected particle size preference and reduced the exploratory pecking behavior of the birds.

Aquaporin 8ab is required in zebrafish embryonic intestine development.

The aquaporin 8 (AQP8) is a small integral membrane protein that selectively transports water and other small uncharged solutes across cell plasma membranes. It has been demonstrated that AQP8 is ubiquitously present in various tissues and organs of mammals, and participates in many physiological and pathological processes. Recent studies showed that AQP8 is highly expressed in the columnar epithelial cells of mammalian colonic mucosa facing lumen, indicating that AQP8 plays potential roles in the physiology and pathophysiology of gastrointestinal tract. However, the role of AQP8 during gastrointestinal tract development is unclear. In the present study, RT-PCR results reveal that the zebrafish genome encodes three kinds of aqp8s ( aqp8aa, aqp8ab, and aqp8b). We use whole mount in situ hybridization to describe aqp8 genes spatiotemporal expression pattern, and the results show that aqp8ab mRNA is detectable mainly in the zebrafish embryonic intestine. To reveal the details of aqp8ab distribution, histological sections are employed. Transverse sections indicate that aqp8ab mRNA expression is more intense in the layer lining the intestinal cavity. Knockout of aqp8ab using the CRISPR/Cas9 system induces intestine development defects and abnormal formation of intestinal lumen. In addition, aqp8ab mRNA significantly rescues the intestine defects in the aqp8ab mutant. These results indicate that aqp8ab is required in the intestine development of zebrafish.

Mesenchymal-epithelial interaction regulates gastrointestinal tract development in mouse embryos.

After gut tube patterning in early embryos, the cellular and molecular changes of developing stomach and intestine remain largely unknown. Here, combining single-cell RNA sequencing and spatial RNA sequencing, we construct a spatiotemporal transcriptomic landscape of the mouse stomach and intestine during embryonic days E9.5-E15.5. Several subpopulations are identified, including Lox+ stomach mesenchyme, Aldh1a3+ small-intestinal mesenchyme, and Adamdec1+ large-intestinal mesenchyme. The regionalization and heterogeneity of both the epithelium and the mesenchyme can be traced back to E9.5. The spatiotemporal distributions of cell clusters and the mesenchymal-epithelial interaction analysis indicate that a coordinated development of the epithelium and mesenchyme contribute to the stomach regionalization, intestine segmentation, and villus formation. Using the gut tube-derived organoids, we find that the cell fate of the foregut and hindgut can be switched by the regional niche factors, including fibroblast growth factors (FGFs) and retinoic acid (RA). This work lays a foundation for further dissection of the mechanisms governing this process.

The Microbiome as a Gateway to Prevention of Allergic Disease Development

Allergic diseases exclusively affect tissues that face environmental challenges and harbor endogenous bacterial microbiota. The microbes inhabiting the affected tissues may not be mere bystanders in this process but actively affect the risk of allergic sensitization, disease development, and exacerbation or abatement of symptoms. Experimental evidence provides several plausible means by which the human microbiota could influence the development of allergic diseases including, but not limited to, effects on antigen presentation and induction of tolerance and allergen permeation by endorsing or disrupting epithelial barrier integrity. Epidemiological evidence attests to the significance of age-appropriate, nonpathogenic microbiota development in skin, gastrointestinal tract, and airways for protection against allergic disease development. Thus, there exist potential targets for preventive actions either in the prenatal or postnatal period. These could include maternal dietary interventions, antibiotic stewardship for both the mother and infant, reducing elective cesarean deliveries, and understanding barriers to breastfeeding and timing of food diversification. In here, we will review the current understanding and evidence of allergy-associated human microbiota patterns, their role in the development of allergic diseases, and how we could harness these associations to our benefit against allergies.

Effect of feeding calcium gluconate embedded in a hydrogenated fat matrix on feed intake, gastrointestinal fermentation and morphology, intestinal brush border enzyme activity and blood metabolites in growing lambs.

Gluconate salts have been identified as a butyrate precursor when fed to non-ruminant species and may increase the butyrate concentration in the large intestine supporting gastrointestinal health and development. The objective of this study was to evaluate the dose response of hydrogenated fat-embedded calcium gluconate (HFCG) on performance and gastrointestinal tract (GIT) development in growing lambs. Thirty-two wether lambs were used in a randomized complete block design and assigned to 1 of 4 treatments differing in the inclusion of HFCG: 0.0% (CON), 0.075% (LOW), 0.30% (MED), and 0.60% of the diet (HIGH). Lambs were allocated into individual pens and fed ad libitum with feed delivered twice daily. Feed intake was recorded daily, and body weight (BW) was assessed at the beginning and the end of the 29-d period. Blood was sampled on day 21, prior to feeding and 6 h post-feeding to evaluate changes in β-hydroxybutyrate, glucose, and insulin concentrations. Total fecal collection was conducted during days 25 to 28 to assess apparent total tract digestibility. On day 29, lambs were slaughtered, and the entire GIT was separated by region to enable sampling of tissue and digesta. Data were analyzed to assess linear, quadratic, and cubic effects of HFCG dose. Final BW, average daily gain, and dry matter intake decreased linearly (P ≤ 0.02) with increasing HFCG. Increasing inclusion of HFCG linearly decreased (P = 0.01) the thickness of the stratum corneum in ruminal papillae but did not affect other strata (P ≥ 0.34). Omasal digesta weight linearly decreased (P = 0.01) as the concentration of HFCG increased and abomasal digesta weight was cubically affected (P = 0.03) the increasing dose of HFCG. Short-chain fatty acid concentration in the cecum was cubically affected (P < 0.01) with increasing dose of HFCG where low dose had the greatest concentration. Moreover, increasing the dietary supply of HFCG linearly increased the proportion of acetate (P = 0.04) in the cecum and linearly decreased the proportion of propionate in the digesta of both the cecum (P < 0.01) and colon (P = 0.01). Colon crypt depth was quadratically (P = 0.03) affected with the increasing dose of HFCG, where lambs fed MED had greatest crypt depth. We conclude that feeding HFCG to growing lambs did not increase butyrate concentration in the large intestine and consequently does not increase the absorptive surface area of the whole tract, the size of the GIT, or the functionality of the intestine.

The Dynamics of Chromatin Accessibility Prompted by Butyrate-Induced Chromatin Modification in Bovine Cells

Butyrate is produced by microbe fermentation in the rumen, and its supplementation results in rumen development. Butyrate-induced experiments are valuable in studying nutrient metabolism, cell growth, and functional genomics. This study aimed to characterize accessible chromatin regions and the dynamics of genomic accessibility prompted by butyrate-induced histone modifications in bovine cells. An average of 117,569 accessible chromatin regions were identified for all samples, and 21,347 differentially accessible regions (DARs) for butyrate. Most of the DARs were in distal intergenic regions, introns, and promoters. Gene ontology enrichment resulted in important terms related to the digestive system, regulation of epithelial cells, and cell adhesion. Ingenuity Pathway Analysis (IPA) identified critical networks (e.g., digestive system development, cell morphology and assembly, and cell cycle); canonical pathways (e.g., TGFβ, Integrin-linked kinase, and epithelial adherens junction); and upstream regulators (e.g., TGFβ1, FOS, JUNB, ATF3, and KLFs). Co-expression analysis further showcased the TGFβ and Integrin-linked kinase (ILK)-signaling pathways, which play roles in rumen development through cellular adhesions. This study is the first to provide a genome-wide characterization of differential, open chromatin regions for bovine cells by butyrate-induced treatment. These results provide valuable information for future studies of the butyrate functions in cattle gastrointestinal tract development.

Threshold concepts encountered by second year medical students in a Basic Health Science module; a qualitative study.

To explore threshold concepts in a Basic Health Sciences module. The qualitative study was conducted at the Islamabad Medical and Dental College, Islamabad, Pakistan, in March 2019, and comprised students and faculty members in the gastrointestinal tract module of spiral I of the integrated modular curriculum in Basic Health Sciences. Data on student experiences was collected using semi-structured interviews with open-ended questions. The data was coded and themes were identified by the researchers independently. A thematic matrix was produced, cross-referencing data relating to troublesome areas identified by the students against the threshold concept criteria. The identified themes were discussed among the researchers to reach consensus. Only the identified themes were taken as the expected threshold concepts in the gastrointestinal tract module. Of the 18 subjects, 14(77.8%) were students and 4(22.2%) were facilitators. There were 8 areas identified by the students as troublesome in the module; development of gastrointestinal tract, anatomical relations, electron transport chain, histology of gastrointestinal tract mucosa, peritoneal disposition, anal canal and ischioanal fossae, peristalsis, and absorption across gastrointestinal tract mucosa. Only development of gastrointestinal tract appeared to cross-match with all the criteria outlined for threshold concepts. The troublesome areas identified by the teachers were development of gastrointestinal tract, peritoneal disposition, anatomical relations, absorption across gastrointestinal tract and peristalsis. Development of gastrointestinal tract was found to be the threshold concept in the system-based integrated module of gastrointestinal tract. Most of the students found their previous knowledge inadequate in learning concepts of the module.

The impact of different inclusion levels of whole barley in feed on growth performance, carcass, and gastrointestinal traits of broiler chickens

The aim of the present research was to evaluate the effect of feeding graded levels of whole barley (WB) on broiler chicken growth and carcass performance, gastrointestinal morphology, and function. A total of 800 male Ross 308 broiler chickens (1-day-old) were randomly assigned to four treatment groups with four replicate pens of 50 birds each. Diets differed in their WB dosage: without WB (NO-WB); low WB amount (LOW-WB) dosages: 4% (1–7 days of age), 8% (8–21 days of age), 15% (22–35 days of age); medium WB amount (MEDIUM-WB) dosages: 6% (1–7 days of age), 12% (8–21 days of age), 20% (22–35 days of age); high WB amount (HIGH-WB) dosages: 8% (1–7 days of age) 16% (8–21 days of age), 25% (22–35 days of age). Body weight, average daily gain, and mortality of chickens did not statistically differ between treatments (P &amp;gt; 0.05). The feed conversion ratio was higher in the treatments diluted with WB. There were no differences in ammonia nitrogen concentration except for increased butyrate concentration in the caecum and reduced digesta viscosity in the broiler ileum in groups fed LOW-WB, MEDIUM-WB, and HIGH-WB diets (P &amp;lt; 0.05). The high WB amount in the diets increased Lactobacillus spp. in the ileal contents and improved ileum morphology (P &amp;lt; 0.05). The inclusion of graded levels of WB in the diets had no effect on carcass performance but it seemed to enhance the gastrointestinal tract development.