Responses of growth performance,antioxidant function,small intestinal morphology and mRNA expression of jejunal tight junction protein to dietary iron in yellow-feathered broilers

This study aimed to investigate the dose-effect of iron on growth performance,antioxidant function.intestinal morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.A total of 7201-d-old yellow-feathered maleb roilers were allocated to 9 treatments with 8 replicate cages of 10 birds per cage.The dietary treatments were consisted of a basal diet(contained 79.6 mg Fe kg^(-1))supplemented with 0,20,40,60,80,160,320,640,and 1,280 mg Fe kg^(-1)in the form of FeSO_(4)·7H_(2)O.Compared with the birds in the control group,birds supplemented with 20mg Fe kg^(-1)had higher average daily gain(ADG)(P<0.0001).Adding 640 and 1,280 mg Fe kg^(-1)significantly decreased ADG(P<0.0001)and average daily feed intake(ADFI)(P<0.0001)compared with supplementation of 20mg Fe kg^(-1).Malondialdehyde(MDA)concentration in plasma and duodenum increased linearly(P<0.0001),but MDA concentration in liver and jejunum increased linearly(P<0.05)or quadratically(P<0.05)with increased dietary Fe concentration.The villus height(VH)in duodenum and jejunum,and the ratio of villus height to crypt depth(V/C)in duodenum decreased linearly(P?0.05)as dietary Feincreased.As dietary Fe increased,the jejunal relative mRNA abundance of claudin-1 decreased linearly(P=0.001),but the jejunal relative mRNA abundance of zona occludens-1(ZO-1)and occludin decreased linearly(P?0.05)or quadratically(P?0.05).Compared with the supplementation of 20 mg Fe kg^(-1),the supplementation of640 mg Fe kg^(-1)or higher increased(P?0.05)MDA concentrations in plasma,duodenum,and jejunum,decreased VH in the duodenum and jejunum,and the addition of 1,280 mg Fe kg^(-1)reduced(P?0.05)the jejunal tight junction protein(claudin-1,ZO-1,occludin)mRNA abundance.In summary,640 mg of supplemental Fe kg^(-1)or greater was associated with decreased growth performance,increased oxidative stress,disrupted intestinal morphology,and reduced mRNA expression of jejunal tight junction protein.

Impacts of dietary supplementation of bamboo vinegar and charcoal powder on growth performance,intestinal morphology,and gut microflora of large-scale loach Paramisgurnus dabryanus

Although accumulating data demonstrate that dietary supplementation of bamboo vinegar and charcoal powder(BVC)can significantly strengthen the immunity and boost the growth of domestic animals,its application potency still awaits verification in commercial fish species such as the large-scale loach Paramisgurnus dabryanus.The impacts of 90-day dietary supplementation of 1%and 2%BVC on survival and growth performance of the loach,and on the intestinal morphological characteristics and gut microflora were analyzed.Our data show that the large-scale loach supplied with BVC at the experimental doses had significant higher survival rates and better growth performance(indicated by greater weight gain(1.13–1.14 times),higher specific growth rate(1.04 times),and lower feed conversion ratio(0.88–0.89 times))compared to that of the control(P<0.05).Histological examination revealed significant longer villus(3.22–5.54 times),deeper crypt(1.77–1.87 times),and thicker muscle(1.59–3.17 times)in the intestines of large-scale loach fed with BVC(P<0.05).Furthermore,we found that the gut microflora consisted of significantly fewer proportions of potential pathogenic bacterial species(Aeromonas veronii and Escherichia coli),but significantly greater proportions of beneficial microbes(Lactococus raffinolactis and Faecalibacterium prausnitzii).Therefore,dietary intake of BVC can promote intestinal tract development and optimize gut microflora,by which the survival and growth of large-scale loach may be improved.

Alginate oligosaccharide-induced intestinal morphology, barrier function and epithelium apoptosis modifications have beneficial effects on the growth performance of weaned pigs

Background: Alginate oligosaccharide(AOS), produced from alginate by alginate lyase-mediated depolymerisation, is a potential substitute for antibiotics and possesses growth-enhancing effects. Nevertheless, the mechanisms by which AOS regulates porcine growth remain to be elucidated. Therefore, we investigated the AOS-mediated changes in the growth performance of weaned pigs by determining the intestinal morphology, barrier function,as well as epithelium apoptosis.Methods: Twenty-four weaned pigs were distributed into two groups(n = 12) and received either a basal diet(control group) or the same diet supplemented with 100 mg/kg AOS. On d 15, D-xylose(0.1 g/kg body weight)was orally administrated to eight randomly selected pigs per treatment, and their serum and intestinal mucosa samples were collected 1 h later.Results: Our results showed that inclusion of AOS in the diet for 2 wk increased(P < 0.05) the average daily body weight gain in weaned pigs. Notably, AOS supplementation ameliorated the intestinal morphology and barrier function, as suggested by the enhanced(P < 0.05) intestinal villus height, secretory immunoglobulin A content and goblet cell counts. Compared to the control group, AOS ingestion both decreased(P < 0.05) the total apoptotic percentage and increased(P < 0.05) the proportion of S phase in the intestinal epithelial cells. Furthermore, AOS not only up-regulated(P < 0.05) the B-cell lymphoma-2(BCL2) transcriptional level but also down-regulated(P < 0.05) the B-cell lymphoma-2-associated X protein(BAX), cysteinyl aspartate-specific proteinase-3(caspase-3) and caspase-9 transcriptional levels in the small intestine.Conclusions: In summary, this study provides evidence that supplemental AOS beneficially affects the growth performance of weaned pigs, which may result from the improved intestinal morphology and barrier function,as well as the inhibited enterocyte death, through reducing apoptosis via mitochondria-dependent apoptosis.

Effects of Dietary Stachyose on Growth Performance, Digestive Enzyme Activities and Intestinal Morphology of Juvenile Turbot(Scophthalmus maximus L)

A 12-week feeding trial was conducted to evaluate the effects of dietary stachyose on the growth performance, digestive enzymes activities and intestinal structures of juvenile turbot(Scophthalmus maximus L). Five isonitrogenous(49.58% crude protein) and isolipidic(10.50% crude lipid) diets were formulated to contain 0(Control), 0.625%(S-0.625), 1.25%(S-1.25), 2.5%(S-2.5) and 5%(S-5) stachyose, respectively. With the increase of stachyose level, the growth performance and feed utilization of turbot, such as the specific growth rate, final mean body weight, weight gain rate and feed efficiency, increased significantly(P < 0.05) and then stabilized. The feed intake of fish fed S-5 was significantly higher(P < 0.05) than that of fish in other groups. The activities of trypsin, intestinal caseinolytic, stomach and intestinal amylase were significantly influenced by stachyose(P < 0.05). The highest values of trypsin and intestinal caseinolytic activities were observed in group S-1.25, while the highest activity of stomach amylase and the lowest activity of intestine amylase were observed in group S-5. No lesion or damage was found on the distal intestine structures of fish from all treatments, while the height of simple folds in the distal intestine was significantly increased(P< 0.05) when 1.25% or 2.5% stachyose was added in the diets. These results indicated that moderate level of stachyose(1.25%) improves the growth performance, feed utilization, digestive enzyme activities and the distal intestine structures of juvenile turbot.

Effects of different proportions of two Bacillus sp. on the growth performance, small intestinal morphology, caecal microbiota and plasma biochemical profile of Chinese Huainan Partridge Shank chickens

A total of 900 one-d-old Chinese Huainan Partridge Shank chickens were randomly allocated into nine groups with five replicates of 20 each.Birds were fed with basal diet,basal diet supplemented with 150 mg kg^（–1） aureomycin,basal diet supplemented with different proportions of Bacillus licheniformis and Bacillus subtilis,which was 0：1.0×10~6,2.5×10~5：7.5×10~5,3.3×10~5：6.6×10~5,5.0×10~5：5.0×10~5,6.6×10~5：3.3×10~5,7.5×10~5：2.5×10~5 and 1.0×10~6：0,respectively.The duration of the experiment was 56 d.The results indicated that dietary supplementation of 6.6×10~5：3.3×10~5 of B.lichenifornis：B.subtilis improved final body weight,increased the average daily gain,and reduced feed/gain ratio（P〈0.05）.The numbers of total Lactobacillus and Bifidobacterium sp.in the caecum significantly increased,and the numbers of Escherichia coli and Salmonella sp.significantly declined compared to that of the control（P〈0.05）.Intestinal villous height and villous height to crypt depth ratio of the duodenum,jejunum,and ileum were significantly higher than that of the control,and intestinal crypt depth of the duodenum and ileum was significantly lower（P〈0.05）.The total antioxidant capacity,total superoxide dismutase,and glutathione peroxidase ability in plasma significantly improved,while the malondialdehyde concentration in plasma decreased（P〈0.05）.Compared to the control,plasma concentrations of ammonia,uric acid and urea nitrogen and the activity of xanthine oxidase were reduced（P〈0.05）.In conclusion,an inclusion of 6.6×10~5：3.3×10~5 of B.licheniformis：B.subtilis to the diet improved the growth performance,caecal microbiota,plasma biochemical profile,and significantly improved the small intestine morphology,while reducing the mortality rate.

Effects of conditioners(single-layer, double-layer and retentionconditioner) on the growth performance, meat quality and intestinal morphology of growing and finishing pigs

This experiment was conducted to investigate the effects of feed conditioners(single-layer, double-layer and retentionconditioner) on the growth performance, meat quality and intestinal morphology of pigs throughout the growing to finishing phase. A total of 96 growing pigs((28.70±3.20) kg) were selected and randomized into three treatment groups with four replicates per group. Eight pigs were used per replicate for the 17-week feeding trial. The grower diet was given at 0 to 6 weeks and a finisher diet was given at 6 to 17 weeks. The treatments were as follows: SC diet(control; single-layer conditioning), DC diet(double-layer conditioning), and RC diet(retention-conditioning). Starch gelatinization was significantly higher(P<0.05) in the RC treatment than in the SC treatment, however, there was no significant difference in the starch gelatinization between the DC group and the RC group. In the growing phase, the feed to gain index(F:G) was significantly lower(P<0.05) in the RC group than in the SC and DC groups. Between growing and finishing, the F:G was the lowest(P<0.05) in the SC group compared to the RC or DC group. Drip loss, a measurement of meat quality, was significantly lower(P<0.05) in longissimus dorsi tissue collected from pigs fed the RC diet than in tissues collected from pigs fed the SC diet. The intestinal quality of the duodenum and jejunum tissues showed a significant increase(P<0.05) in the crypt depth and villus height in the RC group compared to the SC-or DC-treated pigs. These results demonstrated that the retentionconditioner treatment decreased the F:G in growing pigs, improved intestinal morphology and enhanced the meat quality in the finishing pigs. However, the retention-conditioner treatment had a negative impact on growth performance in the finishing pigs.

Effect of riboflavin deficiency on intestinal morphology,jejunum mucosa proteomics,and cecal microbiota of Pekin ducks

This study was to determine the effects of riboflavin deficiency(RD)on intestinal development,jejunum mucosa proteome,cecal short-chain fatty acids(SCFA)profiling,and cecal microbial diversity and community of starter Pekin ducks.Male white Pekin ducks(1 d old,n=240)were allocated into 2 groups,with 12 replicates and 10 birds per replicate in each group.For 21 d,all ducks had ad libitum access to either an RD or a riboflavin adequate(control,CON)diet,formulated by supplementing a basal diet with 0 or 10 mg riboflavin per kg of diet,respectively.Compared to the CON group,growth retardation,high mortality,and poor riboflavin status were observed in the RD group.Furthermore,RD reduced the villus height and the ratio of villus height to crypt depth of jejunum and ileum(P<0.05),indicating morphological alterations of the small intestine.In addition,dietary RD enhanced relative cecum weight and decreased cecal SCFA concentrations(P<0.05),including propionate,isobutyrate,butyrate,and isovalerate.The jejunum mucosa proteomics showed that 208 proteins were upregulated and 229 proteins were downregulated in the RD group compared to those in the CON group.Among these,RD mainly suppressed intestinal absorption and energy generation processes such as glycolysis and gluconeogenesis,fatty acid beta oxidation,tricarboxylic acid cycle,and oxidative phosphorylation,leading to impaired ATP generation.In addition,RD decreased the community richness and diversity of the bacterial community in the cecum of ducks.Specifically,RD reduced the abundance of butyrate-producing bacteria in the cecum(P<0.05),such as Eubacterium coprostanoligenes,Prevotella and Faecalibacterium.Dietary RD resulted in growth depression and intestinal hypofunction of Pekin ducks,which could be associated with impaired intestinal absorption and energy generation processes in intestinal mucosa,as well as gut microbiota dysbiosis.These findings contribute to our understanding of the mechanisms of intestinal hypofunction due to RD.

Dietary eubiotics of microbial muramidase and glycan improve intestinal villi,ileum microbiota composition and production trait of broiler

Background Optimal gut health is important to maximize growth performance and feed efficiency in broiler chickens.A total of 1,365 one-day-old male Ross 308 broiler chickens were randomly divided into 5 treatments groups with 21 replicates,13 birds per replicate.The present research investigated effects of microbial muramidase or a precision glycan alone or in combination on growth performance,apparent total tract digestibility,total blood carotenoid content,intestinal villus length,meat quality and gut microbiota in broiler chickens.Treatments included:NC:negative control(basal diet group);PC:positive control(basal diet+0.02%probiotics);MR:basal diet+0.035%microbial muramidase;PG:basal diet+0.1%precision glycan;and MRPG:basal diet+0.025%MR+0.1%PG,respectively.Results MRPG group increased the body weight gain and feed intake(P<0.05)compared with NC group.Moreover,it significantly increased total serum carotenoid(P<0.05)and MRPG altered the microbial diversity in ileum contents.The MRPG treatment group increased the abundance of the phylum Firmicutes,and family Lachnospiraceae,Ruminococcaceae,Oscillospiraceae,Lactobacillaceae,Peptostreptococcaceae and decreased the abundance of the phylum Campilobacterota,Bacteroidota and family Bacteroidaceae.Compared with the NC group,the chickens fed MRPG showed significantly increased in duodenum villus length at end the trial.Conclusion In this study,overall results showed that the synergetic effects of MR and PG showed enhancing growth performance,total serum carotenoid level and altering gut microbiota composition of broilers.The current research indicates that co-supplementation of MR and PG in broiler diets enhances intestinal health,consequently leading to an increased broiler production.

Effects of yeast products on the intestinal morphology, barrier function, cytokine expression, and antioxidant system of weaned piglets

The goal of this study was to evaluate the effects of a mixture of yeast culture, cell wall hydrolysates, and yeast extracts（collectively ＂yeast products,＂ YP） on the performance, intestinal physiology, and health of weaned piglets. A total of 90 piglets weaned at 21 d of age were blocked by body weight, sex, and litter and randomly assigned to one of three treatments for a 14-d feeding experiment, including（1） a basal diet（control）,（2） 1.2 g/kg of YP, and（3） 20 mg/kg of colistin sulfate（CSE）. No statistically significant differences were observed in average daily feed intake, average daily weight gain, or gain-to-feed ratio among CSE, YP, and control piglets. Increased prevalence of diarrhea was observed among piglets fed the YP diet, whereas diarrhea was less prevalent among those fed CSE. Duodenal and jejunal villus height and duodenal crypt depth were greater in the control group than they were in the YP or CSE groups. Intraepithelial lymphocytes（IEL） in the duodenal and jejunal villi were enhanced by YP, whereas IEL in the ileal villi were reduced in weaned piglets fed YP. Secretion of jejunal and ileal interleukin-10（IL-10） was higher and intestinal and serum antioxidant indexes were affected by YP and CSE. In YP- and CSE-supplemented animals, serum D-lactate concentration and diamine oxidase（DAO） activity were both increased, and intestinal mR NA expressions of occludin and ZO-1 were reduced as compared to the control animals. In conclusion, YP supplementation in the diets of weaned piglets appears to increase the incidence of diarrhea and has adverse effects on intestinal morphology and barrier function.

Imbalanced dietary methionine-to-sulfur amino acid ratio can affect amino acid profiles, antioxidant capacity, and intestinal morphology of piglets

Animal protein sources such as fishmeal and plasma powder are excellent and indispensable sources of energy,amino acid s,and minerals in animal production.Amino acid imbalance,especially methionine-to-sulfur amino acid(Met:SAA)ratio,caused by an imbalance of animal protein meal leads to growth restriction.This study was conducted to evaluate the effects of imbalanced Met:SAA ratio supplementation of different animal protein source diets on growth performance,plasma amino acid profiles,antioxidant capacity and intestinal morphology in a piglet model.Twenty-four weaned piglets(castrated males;BW=10.46±0.34 kg),assigned randomly into 3 groups(8 piglets/group),were fed for 28 d.Three experimental diets of equal energy and crude protein levels were as follows:1)a corn-soybean basal diet with a Met:SAA ratio at 0.51(BD);2)a plasma powder diet with a low Met:SAA ratio at 0.41(L-MR);3)a fishmeal diet with a high Met:SAA ratio at0.61(H-MR).Results revealed that compared to BD,L-MR significantly decreased(P<0.05)the activities of plasma total antioxidant capacity and glutathione peroxidase,plasma amino acid profiles,and significantly reduced(P<0.05)villus height and crypt depth in the duodenum and jejunum.Additionally,L-MR significantly reduced(P<0.05)the mRNA expression level of solute carrier family 7 member 9(SIC7 A9)in the ileum,and significantly increased(P<0.05)mRNA expression levels of zonula occludens-1(ZO-1)in the duodenum,and Claudin-1,ZO-1,sodium-coupled neutral amino acid transporters 2(SNAT2)and SIC7 A7 in the j ejunum.HMR significantly increased(P<0.05)plasma SAA levels,and significantly reduced(P<0.05)average daily feed intake,villus height,and villus height-to-crypt depth(VH:CD)ratio in the ileum compared to BD.In conclusion,L-MR may result in oxidative stress and villous atrophy but proves beneficial in improving intestinal barrier function and the activity of amino acid transporters for compensatory growth.H-MR may impair intestinal growth and development for weaned piglets.The research provides a guidance on the adequate Met:SAA ratio(0.51)supplementation in diet structure for weaned piglets.

Delivery routes for probiotics: Effects on broiler performance,intestinal morphology and gut microflora

Four delivery routes, via, feed, water, litter and oral gavage, were examined for their efficacy in delivering a novel probiotic of poultry origin, Lactobacillus johnsonii, to broilers. Seven treatments of 6 replicates each were allocated using 336 one-day-old Cobb broiler chicks. The treatments consisted of a basal diet with the probiotic candidate, L. johnsonii, added to the feed, and three treatments with L. johnsonii added to the drinking water, sprayed on the litter, or gavaged orally. In addition, a positive control treatment received the basal diet supplemented with zinc-bacitracin(Zn B, 50 mg/kg). The probiotic strain of L.johnsonii was detected in the ileum of the chicks for all four delivery routes. However, the addition of L.johnsonii as a probiotic candidate did not improve body weight gain, feed intake and feed conversion ratio of broiler chickens raised on litter during the 5-week experimental period regardless of the route of administration. The probiotic treatments, regardless of the routes of delivery, affected(P < 0.05) the pH of the caecal digesta and tended(P = 0.06) to affect the p H of the ileal digesta on d 7, but the effect disappeared as the birds grew older. All probiotic treatments reduced the number of Enterobacteria in the caeca on d 21, and tended(P < 0.054) to reduce it in the ileum and caeca on d 7 and in the ileum on d 21 compared with the controls. The probiotic also tended to increase the number of lactic acid bacteria and lactobacilli in the ileum and caeca on d 7, but this trend was not evident on d 21. The trend appeared most pronounced when the probiotic was delivered orally or via litter. The probiotic also decreased(P <0.05) the population of Clostridium perfringens rapidly from an early age to d 21 in the caeca, leading to a3-fold decrease in the number of C. perfringens between d 7 and 21. It also showed that the probiotic treatment presented the lowest number of C. perfringens in the caeca. Delivery of the probiotic through feed, water and litter increased(P <0.01) the weight of the pancreas on d 21, but the probiotic did not affect other morphometric parameters of the gut. Furthermore, the probiotic did not affect the p H and the concentrations of short chain fatty acids and lactic acid in either the ileum or caeca.

Effect of Glutamine Supplementation on Intestinal Mucosal Protein,DNA and Mucosal Morphology of Early-Weaned Piglets

Forty piglets weaned at 21 days age were randomly assigned to one of two groups. The treatment group contained 1. 2% glutamine. The diets were calculated to be isonitrogenous and isoenergetic, each treatment contained five replicates of four piglets. Five piglets from each dietary treatment were killed at 35 days and 49 days age. The results showed that dietary glutamine supplementation increased jejunal DNA content of piglets in the treatment group at 35 days and 49 days age. There was no significant change of ileum DNA content and intestinal protein content between the treatment and control ones. Dietary glutamine supplementation increased mucosal thickness of piglets in treatment group markedly at 35 days age. The intestinal villus heights were significantly higher in treatment than that in control. The results of electron micrograph showed that dietary glutamine supplementation prevented deterioration of intestinal epithelium, and maintained normal intestinal microvillus structure. The results suggested that glutamine supplementation prevented villus atrophy, and had protective effect on intestinal structure.

Early inoculation with caecal fermentation broth alters small intestine morphology,gene expression of tight junction proteins in the ileum,and the caecal metabolomic profiling of broilers

Background:The establishment of stable microbiota in early life is beneficial to the individual.Changes in the intestinal environment during early life play a crucial role in modulating the gut microbiota.Therefore,early intervention to change the intestinal environment can be regarded as a new regulation strategy for the growth and health of poultry.However,the effects of intestinal environmental changes on host physiology and metabolism are rarely reported.This study was conducted to investigate the effects of early inoculation with caecal fermentation broth on small intestine morphology,gene expression of tight junction proteins in the ileum,and cecum microbial metabolism of broilers.Results:Our data showed that early inoculation with caecal fermentation broth could improve intestine morphology.The small intestine villus height was significantly increased(P<0.05)in the intervened broilers compared to the control group,especially on day 28.A similar result was observed in the ratio of villus height to crypt depth(P<0.05).Meanwhile,we found early inoculation significantly increased(P<0.05)the expression levels of zonula occludens-1(ZO1)on days 14 and 28,claudin-1(CLDN1)on day 28,whereas the gene expression of claudin-2(CLDN2)was significantly decreased(P<0.05)on days 14 and 28.Gas chromatography time-of-flight/mass spectrometry(GC-TOF/MS)technology was further implemented to systematically evaluate the microbial metabolite profiles.Principal component analysis(PCA)and orthogonal partial least squares discriminant analysis(OPLS-DA)displayed a distinct trend towards separation between the fermentation broth group(F group)and the control group(C group).The differentially expressed metabolites were identified,and they were mainly functionally enriched in beta-alanine metabolism and biosynthesis of unsaturated fatty acids.In addition,1,3-diaminopropane was selected as a key biomarker that responded to early inoculation with caecal fermentation broth.Conclusions:These results provide insight into intestinal metabolomics and confirm that early inoculation with caecal fermentation broth can be used as a potential strategy to improve intestinal health of broilers.

Effects of Starving and Re-feeding Strategies on the Growth Performance and Physiological Characteristics of the Juvenile Tongue Sole(Cynoglossus semilaevis)

Starving and re-feeding trials were conducted to evaluate the effects of starvation duration and recovery times on the growth performance and physiological characteristics of juvenile tongue sole Cynoglossus semilaevis, which included growth, body composition, intestinal morphology and digestive enzymes activities. The fish starved for one(D1), two(D2) and four(D4) days, respectively, were recovered for three(R3, R6, R12), seven(R7, R14, R28) and eleven(R11, R22, R44) folds of starvation days while the control fish were fed constantly. The experiment was conducted for 96 days. The fish individuals in D1R11, D2R14 and D2R22 caught up in weight with the control, indicating that complete compensatory growth existed in these fish individuals. The highest body weight gain and total specific growth rates were observed in D2R22. Food intake increased significantly in most treatments in comparison with that of the control except for D1R7 and D2R22(P < 0.05). Food conversion efficiency and apparent digest coefficient in D2R22 were significantly promoted, being higher than that of the control(P < 0.05). The activities of trypsin and lipase were found to be closely related to the growth performance. The activities of liver and hindgut trypsin, also midgut and hindgut lipase in D2R22 were significantly higher than those of the control(P < 0.05). The fold height(HF) of foregut and midgut increased significantly in D2R22, and HF decreased significantly in D1R3, D2R6 and D4R12(P < 0.05). On our findings, we may conclude that the optimum starving and re-feeding strategy is starving for 2 days and re-feeding for 22 days. And in this starving and re-feeding strategy, the compensatory growth could be mostly attributed to the promotion of food conversion efficiency and digestibility coefficiency.

Morphological Assessment of the Small Intestine of Broilers Fed Dietary Natural Zeolite Including Plant Extract

Many kinds of feed additives （e.g., probiotics, prebiotics, antibiotics, etc.） can be used in chicken diets to stimulate intestinal morphological maturation and, consequently, intestinal function. The aim of this trial was to investigate the possibility that natural zeolite including plant extract （ZEM） could encourage the hypertrophy of intestinal villi and the absorptive function of epithelial cells in broiler chickens. At 7 days old, 64 male Marshall Chunky broilers were divided into four groups, each with four replicates of four chickens. The birds were fed a basal mash diet supplemented with ZEM at 0% （control）, 0.05%, 0.1%, and 0.2% for 42 days. At 49 days old, four chickens from each treatment were killed to obtain intestinal samples. Morphological intestinal assessment was conducted using both a light and a scanning electron microscope. A tendency to increased villus height and cell area could be observed throughout the intestinal segments of the broilers fed ZEM. Particularly, the villus height in the duodenum was significantly increased （P 〈 0.05） in the 0.05% ZEM group when compared with the control group. The area of the villus cells tended to be higher in the ZEM groups in all intestinal regions and showed a significant increase （P 〈 0.05） in the ileal part of the 0.2% ZEM group. Also, the assessment of cells mitosis in the intestinal crypts showed significantly higher numbers （P 〈 0.05） in all levels of ZEM groups in the duodenum and a tendency to increase in value in the jejunum and ileum, as compared with the control group. More protuberated cells and multi-cell clusters were found in the ZEM groups than in the control group, resulting in a rough cellular surface. In conclusion, the present study might suggest that the intestinal villi and epithelial cells on the villus apical surface are hypertrophied in the ZEM groups, and that intestinal villi adapt to enhance their absorption capacity by increasing the absorptive surface area. These results are indicated that ZEM can provide effective nutritive value when used as a feed additive.

Dose-effect Study of Lipoic Acid Supplementation on Growth Performance in a Weaned Rat Model

The present study investigated the doseeffect relationship of graded levels of lipoic acid supplementation on growth performance and small intestinal development in a weaned rat model. Seventy-two weaned Sprague-Dawley rats, were fed semipurified diets （ n = 12 ）, either unsupplemented （ group I） or supplemented with 12.5,25,125, or 250 mg/kg body weight （ BW ） lipoic acid （ groups HI, IV, V, and VI）, with 200 mg/kg BW aureomycin as the antibiot- ic control （ group II）. The experiment lasted 21 days. Growth performance was not significantly different （P 〉 0.05） between rats under the antibiotic control （group I） and rats fed low levels （12. 5 and 25 mg/kg BW） of lipoic acid （groups III and IV）. In contrast,high level （125 and 250 mg/kg BW） lipoic acid supplementation （groups V and VI） （P 〈 0.05 ） reduced weight gain, feed consumption, and feed efficiency. In addition, high levels （125 and 250 mg/kg BW） of lipoic acid significantly （P 〈 0.05） reduced the villus height/crypt depth ratio, as well as the numbers of lactobacillus, total aerobes, and total anerobes in the gastrointestinal tract compared with the other treatments, which meant that high levels of lipoic acid impaired intestinal morphology and disordered the balance of intestinal microbiology. Furthermore,the results showed that high levels of lipoic acid supplementation （ P 〈 0.05 ） elevated interferon- γ and interleukin-2, but dramatically （ P 〈 0.05 ） depressed interleukin-4 and interleukin-10 compared with the low levels of lipoic acid supplementation and the control group, which indicated that high levels of lipoic acid would induce bias of Th1/Th2 lymphocytes. Taken together, the results indicate that lipoic acid supplementation can＇ t improve growth performance and intestinal development of normal animals, especially,high levels （ ≥ 125 mg/kg BW） of lipoic acid supplementation restrained growth performance and intestinal development, in association with unbalance of certain cytokines.

Dietary butyrate,lauric acid and stearic acid improve gut morphology and epithelial cell turnover in weaned piglets

This study was to evaluate the effects of the supplementation of saturated fatty acids with different chain lengths on growth performance,intestinal morphology,epithelial cell proliferation,differentiation and apoptosis in weaned piglets.Thirty-two weaned piglets(Duroc×Landrace×Yorkshire,BW=7.81±0.26 kg)were weaned at 21 d and randomly assigned to 1 of 4 experimental treatments:(1)a basal diet(control);(2)control+0.3% butyrate(BT);(3)control+0.3%lauric acid(LA);(4)control+0.3% stearic acid(SA).All piglets were then slaughtered for tissue sampling after having been fed experimental diets for 28 d after weaning.Supplementation of BT increased the gain-to-feed ratio(G:F)(P<0.05)compared to piglets fed the control diet from 14 to 28 d.In addition,the villus height(VH)to crypt depth(CD)ratio(VH:CD ratio)of the ileum were higher in the BT and LA diets than that of the control diet(P<0.05).The SA-supplemented diet increased ileal VH(P<0.05),whereas the BT-supplemented diet increased jejunal CD(P<0.05).Compared to the control,diets supplemented with BT,LA,or SA all tended to increase jejunal proliferation(Ki67/crypt positive cells)(P=0.190);diets supplemented with BT or SA significantly increased the number of ki67-positive cells in the ileal crypt(P<0.05).Furthermore,in the jejunum,the protein expression of activated caspase 3 and villin were increased in piglets fed BT,LA,or SA diets compared to those on the control diet(P<0.05).In the ileum,compared with the control diet,the BT diet tended to increase the protein level of mammalian phosphorylation target of rapamycin(p-m TOR,P<0.10);LA or SA diets significantly increased p-m TOR protein expression(P<0.05).These results show that dietary supplementation of BT,LA,or SA promotes jejunal cell renewal in weaned piglets.At the same time,increased proliferation of ileal crypt cells by promoting p-m TOR expression has beneficial effects on ileal morphology in weaned piglets.

Piglet growth performance improved by dietary supplementation of porous or nano particles of zinc oxide may be related to the gut microbiota

Previous studies on porous or nano particles zinc oxide(ZnO)in the piglets have mainly focused on growth performance and intestinal inflammation,but have scarcely explored the efficacy on gut microbiota.In addition,the efficacy of nano particles ZnO,which is related to its product quality,remains undefined.This study aimed to determine the efficacy of dietary 500 mg/kg porous or nano particles ZnO on the growth performance and gut microbiota of the weaned piglets.A total of 128 weaned piglets were randomly assigned to the dietary groups:NC(basal diet),PC(basal diet+3,000 mg/kg conventional ZnO),500HiZ(basal diet+500 mg/kg porous particles ZnO),and 500ZNP(basal diet+500 mg/kg nano particles ZnO).Compared with the NC diet group,both 500HiZ and 500ZNP increased(P<0.05)average daily feed intake(1 to 28 d)and average daily gain(1 to 28 d),and the 500ZNP tended to decrease feed to gain ratio(F:G ratio,1 to 28 d)(P=0.09).Both 500HiZ and 500ZNP decreased crypt depth of the ileum and increased claudin-2 in the duodenum and zonula occludens-1 in the ileum(P<0.05).Moreover,both 500HiZ and 500ZNP decreased IL-1βand tumor necrosis factor-a(TNF-a)in the jejunum and decreased TNF-a and IL-6 in the ileum(P<0.05).Both 500HiZ and 500ZNP increased microbialβ-diversity index in the ileum and microbial a-diversity indices in the colon of piglets(P<0.05).The probiotic genera Coprococcus(500ZNP)and Blautia(500HiZ)were positively correlated with the F:G ratio(1to 28 d)in colon of piglets(P<0.05).In addition,500HiZ promoted mitochondrial fusion protein 1(MFN1)and zinc transporter-1(ZnT-1)in the jejunum(P<0.05),whilst 500ZNP decreased MFN1 in the jejunum and ZnT-1 in the ileum(P<0.05).In summary,both 500HiZ and 500ZNP improved the growth performance of piglets,which is likely via the genera Blautia and Coprococcus,respectively.Both 500HiZ and 500ZNP improved barrier function and inflammation of the intestine,and 500HiZ achieved better efficacy than 500ZNP on intestine mitochondrial functions.

Effects of stocking density on growth performance, blood parameters and immunity of growing pigs

This study was conducted to evaluate the effects of different stocking densities on growth performance,blood parameters,intestinal morphology and intestinal immunity of growing pigs.A total of288 male pigs(44.35±0.50 kg)were randomly assigned to groups with stocking densities of 2.46,1.23 and 0.82 m2/pig for a month.The results showed that there was no significant difference on growth performance among groups.Pigs in the stocking density of 0.82 m2/pig had the lowest backfat thickness and spleen weight index among groups(P<0.05).With increasing stocking density,the serum concentrations of blood urea nitrogen(BUN),transglutaminase(TGG),alkaline phosphatase(AKP)and immunoglobulin A(Ig A)were increased,and albumin(ALB),albumin-to-globulin ratio(ALB:GLO),insulin-like growth factor-1(IGF-1)and immunoglobulin(Ig M)were decreased(P<0.05),and cortisol tended to increase and glucose tended to decrease(0.05<P<0.1).Compared with the stocking density of 2.46 m2/pig,the ileal villus height and jejunal villus width decreased in stocking densities of 1.23 and 0.82 m2/pig(P<0.05).The duodenal villus height and ileal villus width in the stocking density of 0.82 m2/pig were the lowest among 3 groups(P<0.05).The content of immunoglobulin A in duodenum,jejunum and ileum mucosa increased along with increasing density(P<0.05).The contents of interleukin(IL)-2 in the spleen or liver and IL-10 in the spleen were higher in the stocking density of 0.82 m2/pig than in other 2 groups.These results showed that stocking density could affect the metabolism,intestinal morphology,and immunity of growing pigs and 1.23 m2/pig may be the suitable stocking density for the growing pigs in the present study.

Effects of varying dietary folic acid during weaning stress of piglets

The present study was conducted to evaluate the effect of dietary folic acid on the growth performance,intestinal morphology,and intestinal epithelial cells renewal in post-weaning piglets.Twenty-eight piglets(weaned at day 21,initial body weight of 6.73±0.62 kg)were randomly allotted to 4 treat-ments with 7 pens per diet and 1 piglet per pen.The piglets were fed the same antibiotic-free and zinc oxide-free basal diets supplemented with folic acid at 0,3,9,and 18 mg/kg for 14 days.The results showed that dietary supplementation with folic acid increased villus height(VH)(P=0.003;linear,P=0.001),VH-to-crypt depth(VH:CD)ratio(P=0.002;linear,P=0.001),villus surface area(VSA)(P=0.026;linear,P=0.010).The analyzed parameters ADG,serum urea nitrogen(BUN)content,VH,VSA,and serum folate(SF)concentration responded linearly to the dietary folic acid concentration when the dietary folic acid concentration was below 4.42,5.26,4.79,3.47,and 3.53 mg/kg respectively(R2=0.995,0.995,0.999,0.999,0.872,P=0.09,0.07,0.09,0.09,0.36,respectively),as assessed by a two-linear broken-line regression.Above these breakpoints,the response of ADG,VH,VSA,and SF plateaued in response to changes in dietary folic acid concentration.Moreover,dietary supplementation with folic acid significantly increased the lactase(P=0.001;linear,P=0.001)and sucrase activities(P=0.021;linear,P=0.010)in the jejunal mucosa of weaned piglets.The mRNA expression of solute carrier family 6 member 19(SLC6a19),solute carrier family 1 member 1(SLC7a1),tumor necrosis factor-α(TNF-α),the number of Ki67 positive cells,and cell shedding rate had a significant linear contrast(P=0.023,0.021,0.038,0.049,and 0.008,respectively)in dietary folic acid groups.In conclusion,our results indicate that folic acid supplementation can improve the growth performance and intestinal morphology of weaned piglets by maintaining the balance of epithelial cell renewal.