Intestinal Absorptive Surface Research Articles

Growth performance, mucosal immunity and disease resistance in goldfish (Carassius auratus) orally administered with Escherichia coli Strain Nissle 1917.

The current research aimed to shed light on the efficacy of Escherichia coli strain Nissle 1917 (EcN) on goldfish (……) growth, gut immunity, morphology, bacterial nutritional enzyme activity and resistance to Aeromonas hydrophila infection. Fish fed with EcN at 106, 107 and 108CFU/g feed for 80days showed an enhancement in growth better than control fish. The gut innate immunity in terms of lysozyme activity, immunoglobulin and total protein levels was increased in the treatment fish with the best result being observed in fish fed EcN at 108CFU/ g. In addition, an increase was noted in the upregulation of immune-relevant genes, namely lysozyme, interleukin-1β, inducible nitric oxide synthase and tumor necrosis factor α of fish intestine. A marked surge in the number of proteolytic and heterotrophic bacteria was noted in the gut of fish nourished with the probiotic. Histological studies exhibited an improvement in the intestinal absorption surface area, intraepithelial lymphocyte count and goblet cell density. Significantly higher survival rate was obtained in fish fed EcN at 108CFU/g compared with the fish fed with the basal diet. These data exhibited the beneficial effect of EcN on goldfish growth, digestive enzymes, intestine heterotrophic bacteria and resistance against Aeromonas hydrophila challenge. This study confirmed the favorable outcomes resulting from the administration of EcN at108 CFU/g.

Exploring fibrous ingredients for fish: The case of feeding sugar beet pulp to tambaquí (Colossoma macropomum)

For a long time, co-products of food processing have been used in animal feed, but far less in fish because of their assumed inability to cope with high-fiber diets. Research on feeding co-products to fish species that naturally consume fibrous diets are yet lacking. We here evaluated the impact of sugar beet pulp in the diet of tambaquí on nutrient metabolism, oxidative stress, inflammation, and intestinal histomorphometry. A total of 18 tambaquí fish (1616 ± 107 g; 2 years old) were randomly divided over 6 similar tanks with 3 fish per tank and randomly attributed to one of the six dietary treatments 0, 5, 10, 15, 20 and 25 % beet pulp addition and reared for 8 weeks. Water quality parameters (pH, NH3–N, EC, TDS, DO, and temperature) were assessed and recorded twice a week for each tank. A quadratic increase in intestinal villus length, paravilli and absorptive surface were observed with beet pulp addition. Ammonia and pH as quality indicators were significantly changing with beet pulp addition. A higher supply of glucogenic substrate to the citric acid cycle was noticed with beet pulp addition due to the positive correlation with blood propionylcarnitine: acetylcarnitine ratio while there was no effect on ketone body synthesis as measured through the 3-hydroxybutyrylcarnitine: acetylcarnitine ratio. No pronounced change of serum and whole fish histamine and lowered concentrations of serum malondialdehyde were observed with beet pulp addition. In conclusion, beet pulp induced a marked increase in intestinal villus architecture without signs of inflammation or oxidative stress. Large-scale studies need to clarify if these features lead to improved growth performance but this work opens options for further study. The non-linear pattern of some blood components with increasing beet pulp may call for future optimal dosing and feed form of beet pulp together.

Endoscopic reversal of roux-en-Y gastric bypass prevents worsening of nutritional outcomes in patients with severe malnutrition

Roux-en-Y gastric bypass (RYGB) can precipitate protein-calorie malnutrition and micronutrient deficiencies. Sonographically guided endoscopic reversal (ER) via deployment of a stent from the gastric pouch to the remnant stomach in RYGB anatomy has emerged as a novel option for increasing both intestinal transit time and absorptive surface area. In this investigation, short-term nutritional outcomes after ER of a RYGB in patients (age ≥ 18) with severe protein-calorie malnutrition from a single academic health center in Minneapolis, Minnesota over a seven-year period (2015-2021) were retrospectively reviewed pre-procedurally, and at six and twelve months post-procedurally. 17 patients underwent ER for severe protein-calorie malnutrition, or dependence on tube feeds (TF) or total parenteral nutrition (TPN). At 6 months post-ER, two patients were no longer malnourished and only on oral nutrition; three patients were liberated from TPN. Laboratory markers of protein-calorie malnutrition, renal function, and micronutrients were not significantly different at six- or twelve-month follow-up (P > 0.05). In all patients, access to the gastric remnant was maintained via stent placement through the gastric pouch or proximal Roux limb throughout the study period and no complications were noted after ER. Despite the small sample size, this investigation revealed that ER of RYGB may prevent progressive deleterious weight loss, and worsening macro- and micro-nutrient deficiencies, though improvement in weight and nutritional parameters was not observed. Overall, ER was found to be a nuanced and safe, advanced technique useful for when remnant access is desired in RYGB patients.

Individual and combined effects of dietary supplementation of probiotic and essential oil on the growth performance, immunity status, gut health and jejunal histomorphology of broiler chickens

The present study was conducted to evaluate the individual and combined effects of probiotic and essential oils on the performance of broilers. Day-old broiler chicks (240) were allocated to 5 groups in completely randomized design to give 6 replications per treatment group with 8 birds in each replicate. The birds of different groups were supplemented with antibiotic growth promoter (CTC 15%) at the level of 335 mg/kg (T1), essential oil formula (TCLVC 1.5×) (T2), L. fermentum NKN51 (107 cfu/g) along with MOS (0.3%) and sodium butyrate (0.03%) (T3), and combination of L. fermentum NKN51 (107 cfu/g) and essential oil formula (TCLVC 1.5×) in presence of MOS (0.3%) and sodium butyrate (0.03%) (T4). The control group was provided basal diet only with no other supplementation. The birds were reared for a period of 6 weeks and examined for growth performance including weekly body weight, average daily gain, weekly FCR, average feed intake, cell mediated and humoral immunity, gut microbiology, jejunal histology and stress parameters including heterophil-lymphocyte ratio and serum corticosterone levels. The group supplemented with combination of probiotic and essential oil formula (TCLVC 1.5×) had significantly better growth performance, cell mediated and humoral immunity and improved jejunal histology in terms of villus height, villus width, VH: CD ratio and intestinal absorptive surface area. No significant difference was observed in stress levels of different groups in terms of heterophil-lymphocyte ratio and serum corticosterone levels. The study depicted that combined supplementation of probiotic and essential oil had affirmative response on performance parameters of broiler chickens.

Adequate levels of dietary sulphur amino acids impart improved liver and gut health in juvenile yellowtail kingfish (Seriola lalandi).

The sulphur amino acids methionine (Met) and cysteine (Cys) and their derivative taurine (Tau) are metabolically active molecules with interlinked roles in nutritional requirements. Deficiencies in these nutrients are linked to poor growth and health; however, the impacts of these deficiencies on organ structure and function are largely unknown. This study examined the effects of dietary Met, Cys and Tau fed at different levels on yellowtail kingfish (YTK) liver histology and surface colour, plasma biochemistry and posterior intestine histology. Samples were collected from two dose-response feeding trials that quantified (1) the Tau requirement and sparing effect of Met by feeding YTK diets containing one of seven levels of Tau at one of two levels of Met and (2) the Met requirement and sparing effect of Cys by feeding YTK diets containing one of five levels of Met at one of two levels of Cys. YTK fed inadequate levels of dietary Met, Cys and Tau exhibited thicker bile ducts, less red livers, more intestinal acidic goblet cell mucus and supranuclear vacuoles and less posterior intestinal absorptive surface area. Further, thicker bile ducts correlated with less red livers (a*, R), whereas increased hepatic fat correlated with a liver yellowing (b*). Our results indicate a shift towards histological properties and functions indicative of improved intrahepatic biliary condition, posterior intestinal nutrient absorption and homoeostasis of YTK fed adequate amounts of Met, Cys and Tau. These findings may assist in formulating aquafeed for optimised gastrointestinal and liver functions and maintaining good health in YTK.

Intestinal Morphometric Changes Induced by a Western-Style Diet in Wistar Rats and GSPE Counter-Regulatory Effect.

Western-style diet is an obesogenic diet for rodents and humans due to its content of saturated fat and refined sugars, mainly sucrose and, in consequence, sucrose-derived fructose. This type of diets relates with intestinal disturbances when consumed regularly. The aim of this work was to analyse the adaptive morphologic and functional changes at intestinal level derived from the unhealthy components of a Cafeteria diet in rats. The effect of grape seed proanthocyanidin extract (GSPE) in the prevention of diet-induced intestinal dysfunction was also analysed. Rats were fed a 17-week cafeteria diet (CAF) without or with oral-GSPE supplementation, either intermittent GSPE administration (SIT-CAF); last 10-day GSPE supplementation at doses of 100 mg/kg and 500 mg/kg day (CORR-100) and (CORR-500) or pre-supplementation with 500 mg/kg GSPE (PRE-CAF). GSPE-CAF supplemented groups showed similar results to CAF diet group regarding morphology and inflammatory score in the duodenum. As an adaptive response to diet, CAF increased intestinal absorptive surface (1.24-fold) all along the intestinal tract and specifically in the small intestine, duodenum, due to increase villus height and a higher villus/crypt ratio, in addition to increase in Goblet cell percentage and inflammatory index. Animals fed GSPE at the current doses and times had higher villus heights and absorptive surface similar to Cafeteria diet group. In the duodenum, villus height correlated with body weight at 17 week and negatively with MLCK gene expression. In the colon, villus height correlated with the percentage of goblet cells. In conclusion, the CAF diet produced adaptive modifications of the intestine by increasing the absorptive area of the small intestine, the percentage of goblet cells and the inflammatory index at the duodenal level. GSPE supplementation can partially reverse the intestinal morphological changes induced by the high fat/sucrose diet when administered intermittently.

Intestinal Deletion of 3-Hydroxy-3-Methylglutaryl-Coenzyme A Reductase Promotes Expansion of the Resident Stem Cell Compartment.

The intestine occupies the critical interface between cholesterol absorption and excretion. Surprisingly little is known about the role of de novo cholesterol synthesis in this organ, and its relationship to whole body cholesterol homeostasis. Here, we investigate the physiological importance of this pathway through genetic deletion of the rate-limiting enzyme. Mice lacking 3-hydroxy-3-methylglutaryl-coenzyme A reductase (Hmgcr) in intestinal villus and crypt epithelial cells were generated using a Villin-Cre transgene. Plasma lipids, intestinal morphology, mevalonate pathway metabolites, and gene expression were analyzed. Mice with intestine-specific loss of Hmgcr were markedly smaller at birth, but gain weight at a rate similar to wild-type littermates, and are viable and fertile into adulthood. Intestine lengths and weights were greater relative to body weight in both male and female Hmgcr intestinal knockout mice. Male intestinal knockout had decreased plasma cholesterol levels, whereas fasting triglycerides were lower in both sexes. Lipidomics revealed substantial reductions in numerous nonsterol isoprenoids and sterol intermediates within the epithelial layer, but cholesterol levels were preserved. Hmgcr intestinal knockout mice also showed robust activation of SREBP-2 (sterol-regulatory element binding protein-2) target genes in the epithelium, including the LDLR (low-density lipoprotein receptor). At the cellular level, loss of Hmgcr is compensated for quickly after birth through a dramatic expansion of the stem cell compartment, which persists into adulthood. Loss of Hmgcr in the intestine is compatible with life through compensatory increases in intestinal absorptive surface area, LDLR expression, and expansion of the resident stem cell compartment.

Growth Hormone Overexpression Induces Hyperphagia and Intestinal Morphophysiological Adaptations to Improve Nutrient Uptake in Zebrafish.

The excess of circulating growth hormone (GH) in most transgenic animals implies mandatory growth resulting in higher metabolic demand. Considering that the intestine is the main organ responsible for the digestion, absorption, and direction of dietary nutrients to other tissues, this study aimed to investigate the mechanisms by which gh overexpression modulates the intestine to support higher growth. For this purpose, we designed an 8-weeks feeding trial to evaluate growth parameters, feed intake, and intestinal morphometric indices in the adult gh-transgenic zebrafish (Danio rerio) model. To access the sensitivity of the intestine to the excess of circulating GH, the messenger RNA (mRNA) expression of intestine GH receptors (GHRs) (ghra and ghrb) was analyzed. In addition, the expression of insulin-like growth factor 1a (igf1a) and genes encoding for di and tripeptide transporters (pept1a and pept1b) were assessed. Gh-transgenic zebrafish had better growth performance and higher feed intake compared to non-transgenic sibling controls. Chronic excess of GH upregulates the expression of its cognate receptor (ghrb) and the main growth factor related to trophic effects in the intestine (igf1a). Moreover, transgenic zebrafish showed an increased intestinal absorptive area and higher expression of crucial genes related to the absorption of products from meal protein degradation. These results reinforce the ability of GH to modulate intestinal morphology and the mechanisms of assimilation of nutrients to sustain the energy demand for the continuous growth induced by the excess of circulating GH.

Impact of Intestinal Urinary Diversion on the Risk of Fracture and Loss of Bone Mass: A Systematic Review.

Patients undergoing intestinal urinary diversion (IUD) may have a higher risk of osteoporosis and risk of fractures due to metabolic acidosis and decrease of intestinal absorption surface. We performed a systematic review of the available literature on the impact of IUD on bone demineralization. We systematically searched PubMed®, for original articles published before April 2020. Primary end points were the risk of fracture and loss of bone density. Secondary outcomes were the metabolic changes in biochemical and urine parameters related to calcium metabolism and histological changes. Our electronic search identified a total of 2417 articles. After a detailed review, we selected 11 studies that addressed the impact of IUD on bone health in 10369 patients. The risk of bone fracture was studied in 3 articles, showing a higher risk in the IUD population. Of the 9 articles evaluating the relation between intestinal urinary diversion and bone density, 5 did find a positive association. One article evaluated the bone metabolism at a cellular level after IUD showing a decrease in bone turnover in this population. Three of the eight studies reporting data on serum parameters related to calcium and phosphate metabolism showed differences. Finally, a correlation between concentration of pyridolines in urine and loss of bone density was found in two of the three studies. Although published data on BMD are contradictory, patients undergoing IUD seem to be at higher risk of bone fractures. Our finding support the need to implement accessible strategies on osteoporosis screening and prevention in IUD patients.

Short communication: Bacillus subtilis C-3102 improves biomass gain, innate defense, and intestinal absorption surface of native Brazilian hybrid Surubim (Pseudoplatystoma corruscans x P. reticulatum)

The aim was to evaluate the effect of a diet supplemented with B. subtilis for a period of 10 days and to verify its effects on the zootechnical performance, hematological parameters, and intestinal histomorphometry of fish. The present study was designed to verify the effects of a commercial product containing Bacillus subtilis C-3102 for short administration period in the diet of Brazilian catfish Pseudoplatystoma sp. The experimental design was completely randomized with five treatments (0, 10, 20, 30, and 40 g of CALSPORIN® kg feed−1) and six replicates. Supplementation with B. subtilis did not influence (p > 0.05) on erythrogram and plasma glucose of fish. However, probiotic supplementation for 10 days was effective and caused beneficial changes in productive performance of the 30 g kg feed−1 group compared to the other groups. In addition, improvements in the immune system, such as an increase in the number of neutrophils, lymphocytes, thrombocytes, and total blood leukocytes were observed in the treated groups, besides increased height and width of the intestinal villi was possibly related with an improvement in nutrient absorption. This study shows the feasibility in to use short time of feeding in the Pseudoplatystoma sp. diet that improved the fish health.

Effect of Shirazi thyme on oxidant status and absorptive surface area of the intestine in cold-induced pulmonary hypertensive broiler chickens.

The effects of Shirazi thyme as a medicinal plant on oxidant status (lipid peroxidation, protein oxidation, total antioxidant capacity, and catalase activity) and absorptive surface area were measured in three segments of the small intestine in cold-induced pulmonary hypertensive chickens. Birds were reared at four groups (thyme 0, 0.25, 0.50, and 1.00 % of diet) for 42 days. To induce pulmonary hypertension, the temperature was gradually decreased. The body weight was increased in thyme-0.25% birds compared to control ones, while it was decreased in thyme-1% of birds. The feed consumption was only increased in thyme-1.00% birds. The feed conversion ratio was lower in thyme-0.25% birds and higher in thyme-1.00% birds than control ones. The duodenal and jejunal villus surface area was lower in thyme-1.00% birds than control ones, while it was greater in the thyme-0.50% birds. The ileal villus surface area and duodenal lamina propria thickness were also greater in thyme-0.50% birds. Lipid peroxidation was only decreased in the duodenum and ileum of thyme-0.50% birds compared to control ones, whereas it was increased in the duodenum and jejunum of thyme-1.00% birds. Catalase activity was only elevated in the duodenum and jejunum of thyme-1.00% fed chickens. Total antioxidant capacity was increased in the duodenum, jejunum, and ileum of thyme-0.50% birds. It is concluded that the Shirazi thyme has beneficial effects on growth performance, intestinal absorptive surface area / secretory system, and pulmonary hypertension response at low doses (0.25 and 0.50% of diet), whereas high dose (1.00% of diet) of this plant may be toxic.

Mechanisms, mishaps and manipulation of iron uptake

Mechanisms, mishaps and manipulation of iron uptake

Intestinal Morphology in Broiler Chickens Supplemented with Propolis and Bee Pollen.

Simple SummaryConsumers are becoming more aware of the nutritional value of foods, and they want to consume food that provides health benefits beyond the provision of essential nutrients. Chicken meat could fulfil the above requirements due to its high nutrient content and relatively low caloric value, and it serves as an interesting basis for functional foods. In this study, we evaluated the effects of propolis and bee pollen, as potential additives, on the intestinal morphology and absorptive surface areas of broiler chickens. The results of this study showed that supplementation of broilers with propolis and/or bee pollen has a profoundly beneficial effect on intestinal morphology and absorptive surface areas. Thus, these natural additives could be used as alternative additives in modern broiler production, while chicken meat can be even more beneficial for human health.The aim of this study was to determine the influence of dietary supplementation with propolis and bee pollen on the intestinal morphology and absorptive surface areas of chickens. Two hundred day-old Ross 308 chickens (100 male and 100 female) were equally allocated into five groups. Throughout the whole study, the control group of chickens was fed with a basal diet, while the experimental groups of chickens were fed with the same diet supplemented with propolis and bee pollen: P1 = 0.25 g of propolis/kg + 20 g of bee pollen/kg; P2 = 0.5 g of propolis/kg; P3 = 1.0 g of propolis/kg; P4 = 20 g of bee pollen/kg. The duodenal villi of chickens from all experimental groups were significantly higher and wider (p < 0.001), while their duodenal villi crypts were significantly deeper (p < 0.001) in comparison with these parameters in chickens from the control group. The villus height to crypt depth ratio, as well as the absorptive surface areas of broiler chickens, were significantly increased (p < 0.001) in experimental groups of chickens in comparison with the control group. These findings suggest that dietary supplementation with propolis and bee pollen has a beneficial effect on broilers chickens’ intestinal morphophysiology.

Proteomics alterations in chicken jejunum caused by 24 h fasting.

The small intestine is the longest part of the chicken (Gallus gallus) gastrointestinal system that is specialized for nutrient absorption. It is known that decrease in intestinal villi area or height in early age can cause a reduction in essential nutrient intake, which may lead to delayed growth and consequently poorer performance of broiler chickens. The small intestinal absorptive surface is known to be affected by various factors, among others things the nutritional state. In our experiment, we aimed to investigate the possible protein expression alterations that lie behind the villus area and height decrease caused by feed deprivation. A total of 24 chickens were divided into three groups, namely ad libitum fed, fasted for 24 h, fasted for 24 h then refed for 2 h. The morphometric parameters were also measured in the duodenum, jejunum and ileum tissue sections using image analysis. Differential proteome analyses from jejunum samples were performed using two-dimensional difference gel electrophoresis followed by tryptic digestion and protein identification by matrix-assisted laser desorption/ionization mass spectrometry. Overall 541 protein spots were detected after 2D. Among them, eleven showed 1.5-fold or higher significant difference in expression and were successfully identified. In response to 24 h fasting, the expression of nine proteins was higher and that of two proteins was lower compared to the ad libitum fed group. The functions of the differentially expressed proteins indicate that the 24 h fasting mainly affects the expression of structural proteins, and proteins involved in lipid transport, general stress response, and intestinal defense.

Orally Dosed Citalopram Stimulates Small Intestinal Mucosal Growth

BackgroundParenterally administered selective serotonin reuptake inhibitors, such as citalopram, increase intestinal mucosal absorptive surface by day 7 of treatment. We hypothesized that enteral citalopram would also induce intestinal mucosal growth, thus allowing for therapy with an oral agent. Materials and methodsFollowing a habituation period, C57BL/6 mice received peanut butter pellets containing 10, 50, or 100 mg/kg/d citalopram for 7 d (n = 5); or 25 mg/kg/d citalopram for 14 (n = 3) or 21 (n = 5) d; or plain peanut butter pellets for 7 (n = 2), 14 (n = 2), or 21 d (n = 3). Two-centimeter ileal segments were harvested and prepared for microscopic assessment of villus height (VH), crypt depth, villus width (VW), and crypt width. Mucosal surface area (MSA) was calculated and data were compared using Student's t-test. ResultsEnteral administration of citalopram had virtually no effect on VH, VW, or crypt depth after 7 d; crypt width decreased significantly (P value range 0.0002 to <0.0001), likely contributing to the increases in MSA (P value range 0.0578 to 0.0006). After 14 d of treatment, citalopram significantly increased VH (P < 0.0001), VW (P = 0.0058), and ileal MSA per mm2 (P = 0.0007). The increase in MSA was sustained at 21 d (P < 0.0001). ConclusionsEnteral citalopram given for 14 d results in increased VH and ileal MSA, which remains increased by day 21. Selective serotonin reuptake inhibitors show potential as oral therapy for serious intestinal disorders such as short bowel syndrome.

Growth performances, carcass traits, meat quality, and blood metabolic parameters in rabbits of local Algerian population and synthetic line.

Aim:The objective of this work was to study the growth performance, slaughter traits, meat quality, and metabolic profile in rabbits of local Algerian population and a synthetic line.Materials and Methods:In total, 120 weaned rabbits were used (60 per group). Growth traits were recorded from weaning (35 days) to slaughter (91 days). At slaughter, carcass traits, meat quality, and metabolic profiles were measured.Results:The synthetic line showed heavier total weight and faster daily weight gain than the local population (+15% and +19%, respectively), better feed conversion (3.92 vs. 4.81 g/g), and heavier weight of cold carcass, and perirenal fat (+15%). No differences were found between the two groups in dressing out percentage, muscular pH, weight of liver, or scapular fat. Wider intestinal villi were found in the synthetic line (+20%, p<0.0001) allowing better absorption surface in this line. The synthetic line also showed higher fat content (3.41% vs . 2.22%, p<0.0001) in the meat and lower protein content (22.02% vs . 18.98%, p=0.0002). Glucose level was 19% higher in the local population than in the synthetic line.Conclusion:The synthetic line is well adapted to the local conditions of Algeria. This line has shown better growth, daily gain, and feed conversion, due to its better intestinal absorption surface.

Histochemistry of goblet cells and micro-computed tomography to study the digestive system in the long-snouted seahorse Hippocampus guttulatus

Sygnathids are agastric teleosts (no stomach), relying on a digestive tract using different mechanisms to process and absorb nutrients. This results in a low digestion efficiency at early stages, forming a mayor bottleneck in the rearing of these fish. In agastric species, the numerous goblet cells present in the oesophagus could be considered as a morphological adaptation that replaces a functional stomach, although the specialization and number of these cells is species-specific and vary throughout the development and intestinal region. The present study aim to characterize the biochemical composition of goblet cells and investigate the morphology of the digestive system during the ontogeny of Hippocampus guttulatus seahorses (from 0 to 60 days post-partum, dpp) in order to understand the mechanisms of nutrient digestion in a species that lacks gastric glands.Goblet cells (GC) appear in the digestive tract of Hippocampus guttulatus from birth on, secreting a large amount of acid (carboxylated) and neutral glycoconjugates (GCs) released in the buccopharyngeal cavity and oesophagus, while sulphated and neutral GCs are detected throughout the complete digestive tract of the seahorses. The midgut mainly secretes neutral and acid (carboxylated) GCs at the early stages (<15 dpp) and acid (sulphated) GCs at later stages, while the hindgut is characterized by the presence of carboxylated and highly sulphated GCs throughout development.Based on the development of the digestive tract observed by 3D reconstructed μCT data, an increase in the intestinal absorption surface can be assumed. This increase is in correspondence with a change in the type of acid GCs observed in the midgut from 15 dpp. The present study demonstrates that the digestive system of H. guttulatus is functional at first feeding, although not fully developed. The different GCs secreted by the goblet cells in the digestive tract of H. guttulatus revealed that the glycosylation patterns vary according to the digestive region and stage of development. Neutral GCs could be involved in the digestion of simple substances (e.g. short chain fatty acids) in early stages of development, while in more advanced stages the change to acid GCs would promote the absorption of proteins. A change in the secretion of goblet cells from 15 dpp, in coincidence with the observation of a progress increase in the intestinal absorption surface, would explain the better digestive efficiency observed from that age.

Egg perivitelline fluid of the invasive snailPomacea canaliculataaffects mice gastrointestinal function and morphology

BackgroundSpecies beloging to the genus Pomacea (Ampullariidae), often referred as apple snails, are freshwater, amphibious snails native to South, Central and North America. Some species such as P. canaliculata have become a driver of ecosystem changes in wetlands and an important rice and taro pest after its introduction to Asia and other parts of the world. Females deposit colored egg clutches above the waterline, a reproductive strategy that exposes the eggs to harsh conditions and terrestrial predation. However, eggs have no reported predators in their native range, probably because of the acquisition of unparalleled biochemical defenses provided by a set of proteins (perivitellins) that nourish embryos and protect them from predators and abiotic factors. Notably, ingestion of egg perivitelline fluid (PVF) decreases rat growth rate and alters their gastrointestinal morphology. The aim of the study is to determine the effect of apple snail egg PVF on mice gut digestive activity, morphology and nutrient absorption.MethodsCarbohydrate digestion by intestinal disaccharidases (sucrase-isomaltase and maltase-glucoamylase) was evaluated ex vivo in mice gavaged with 1 or 4 doses of PVF. Changes in gut morphological and absorptive surface were measured. In addition, alteration on nutrient absorption rates, transport pathways and intestinal permeability was evaluated by luminal perfusions of small intestine with radiolabeled L-proline (absorbed by paracellular and transcellular pathways) and L-arabinose (absorbed exclusively by paracellular pathway).ResultsPerivitelline fluid affected mice displayed significant morphological changes in the small intestine epithelium inducing the appearance of shorter and wider villi as well as fused villi. This resulted in a diminished absorptive surface, notably in the proximal portion. Likewise, the activity of disaccharidases diminished in the proximal portion of the intestine. Total absorption of L-proline increased in treated mice in a dose-dependent manner. There were no differences neither in the ratio of paracellular-to-transcellular absorption of L-proline nor in gut permeability as revealed by the clearance of L-arabinose.DiscussionOral administration of apple snail PVF to mice adversely alters gut morphophysiology by reducing the intestinal absorptive surface, affecting enzymes of sugar metabolism and increasing the absorption rate of nutrients without affecting the relative contribution of the absorption pathways or gut permeability. These results further support the role of PVF in passive anti-predator defenses in Pomacea snail eggs that target the digestive system.

Medical and surgical management of short bowel syndrome

Short bowel syndrome (SBS) is a rare disease, resulting from extensive resection of the small intestine. Depending on the severity of malabsorption, it will lead to intestinal failure, defined as the reduction of gut function below the minimum necessary for the absorption of macronutrients and/or water and electrolytes, resulting in a situation where intravenous supplementation is required. The risk of developing intestinal failure is related to the remaining length of small intestine and the anatomy of the remnant bowel. SBS incidence has been estimated to range from 5 to 10 patients per year per million population. The main consequence of SBS is a marked reduction of intestinal absorption surface and its main complication is undernutrition and hydro-electrolytic abnormalities. Parenteral nutrition (PN), the major treatment of intestinal failure, has long-term complications. In case of PN dependency, treatment with trophic factors can be proposed. Glucagon-like peptide-2 (GLP-2) analogs allow significant reduction of PN dependency and improve quality of life. Rehabilitative surgery should always be proposed, with the primary goal of restoring digestive continuity. Sometimes, an additional surgical procedure, such as an antiperistaltic reversal of a small bowel segment, is performed when restoring digestive continuity in patients with insufficient length of remnant small intestine to enhance the possibility of PN withdrawal. Intestinal transplantation is proposed as a last resort.

The effects of low-protein diets and protease supplementation on broiler chickens in a hot and humid tropical environment.

ObjectiveThis experiment was conducted to investigate the effects of dietary crude protein (CP) level and exogenous protease supplementation on growth performance, serum metabolites, carcass traits, small intestinal morphology and endogenous protease activity in broiler chickens reared under a tropical climate.MethodsA total of 480 day-old male broiler chicks were randomly assigned to eight dietary treatments in a 4×2 factorial arrangement. The main effects were CP level (21.0%, 19.7%, 18.5%, or 17.2% from 1 to 21 days and 19.0%, 17.9%, 16.7%, or 15.6% from 22 to 35 days) and protease enzyme supplementation (0 ppm or 500 ppm). All experimental diets were fortified with synthetic feed-grade lysine, methionine, threonine and tryptophan to provide the minimum amino acid recommended levels for Cobb 500.ResultsReducing dietary CP linearly reduced (p<0.05) growth performance, serum albumin, total protein, and carcass traits and increased (p<0.05) serum triglycerides and abdominal fat. There was no consistent effect of reducing dietary CP on morphological parameters of the intestine and on the pancreatic and intestinal endogenous protease activity (p>0.05). Protease supplementation improved (p<0.05) feed conversion ratio, body weight gain, carcass yield and intestinal absorptive surface area.ConclusionProtease supplementation, as measured by growth performance, intestinal morphology and carcass yield, may alleviate the detrimental effects of low protein diets in broiler chickens.