Intestine Of Broiler Chickens Research Articles

Age-related Regulation of Active Amino Acid Transport in the Ileum of Broiler Chickens.

Broiler chickens grow rapidly within a short period; in this regard, our group had previously reported a decrease in the active transport of glucose in the intestines of broiler chickens with their growth. Therefore, in this study, we compared the active transport process of amino acids in the intestines between 1- and 5-week-old broilers using everted sac, Ussing chamber techniques, and real-time quantitative polymerase chain reaction (RT-PCR). The everted sac experiment showed that amino acids were absorbed from all segments of the small intestine in both age groups. There were no significant differences in the serosal to mucosal ratio between 1- and 5-week-old broilers. The Ussing chamber experiment showed that amino acid-induced short-circuit current (ΔIsc) in the ileal epithelium was significantly greater in the 5-week-old chickens than in the 1-week-old chicks (P=0.035). Membrane conductance, an indicator of ion permeability, showed no significant difference between the two groups. Moreover, the mRNA expression levels of amino acid transporters (ASCT1, EAAT3, B0AT1, and y+LAT1) were significantly elevated in the distal ileum of the 5-week-old broilers compared to those in the 1-week-old broilers (P<0.05), while no significant differences were observed in the mRNA levels of ATB0'+, B0/+AT, rBAT, CAT1, and CAT2 in both groups. Our study provides clear evidence that age-dependent increase in the active transport of amino acid across the ileal epithelium is caused by the high expression of Na+-dependent amino acid transporters in broiler chickens.

Effects of Glutamine on the Mucosal Structure and Immune Cells in the Intestines of Broiler Chickens Challenged with Salmonella Enteritidis

The aim of this study was to investigate the effects of glutamine (Gln) on the intestinal mucosal structure and immune cells of broilers infected with Salmonella Enteritidis. 160 1-d-old commercial Arbor Acres (AA) broilers were randomly selected to receive one of four treatments, each of which had 5 replicates. Each replicate consisted of 8 chicks subjected to a 21-d feeding trial. Group I served as the unchallenged (CON). All birds in groups II (SCC) - IV were challenged with 2.0 × 104 CFU/mL of S. Enteritidis. The birds in groups III and IV were treated with 0.5% and 1.0% Gln. The results showed that S. Enteritidis infection led to a decrease in the relative length and weight, villus height:crypt depth (VH:CD) of the jejunum and ileum, the number of intraepithelial lymphocyte cells, and number of goblet cells and an increase in the number of mast goblet cells compared with the measurements of these parameters in the CON group (p<0.05). In addition, the Gln groups had increased relative length and weight, VH:CD of the jejunum and ileum, numbers of intraepithelial lymphocyte cells, and numbers of goblet cells and decreased crypt depth in the jejunum and ileum and numbers of mast goblet cells compared with the measurements of these parameters in the SCC group (p<0.05). It was concluded that Gln added to broiler diets can effectively alleviate the intestinal mucosal damage caused by S. Enteritidis infection and improve its normal defense barrier function.

Effects of ochratoxin A on membrane phospholipids of the intestine of broiler chickens, practical consequences

Ochratoxin A (OTA) is a mycotoxin produced by various species of Aspergillus and Penicillium. Ochratoxin A was classified as a group 2B carcinogen and is one of the major intestinal pathogenic mycotoxins. One of the most frequent modes of intoxication is consumption of contaminated food with mycotoxins. Feed represents the major cost and has a direct impact on the economical viability of broiler’s production system, since it must contain the necessary elements that allow the animal to express the maximum genetic potential while providing its nutritional requirements. Thus, the animal has to digest the feed and absorb its nutrients, which is in direct correlation with the gastrointestinal tract, especially the small intestine and the development of the mucosal surface area. Once ingested, OTA is absorbed by passive diffusion, mainly the jejunum. Ochratoxin A’s presence affects lipid membranes and could lead to the degradation of their normal structure and functionality. All of these effects contribute to the development of malabsorption. It was very interesting to study the effect of OTA on the layer of phospholipids of the bowel. The experimental group received OTA (0.05 to mg/kg BW) through an intra-peritoneal injection, every other day for 21 days. We noted that feed conversion ratio and average daily gain were reduced. Histological studies showed important alterations at the level of the mucosal membrane of the intestine (villosities, crypts) following intra-peritoneal administration of the mycotoxin. Thinning and enlargement at the base of the villosities, hyperplasia and crypts in irregular forms, blunting and denudation were observed through the examination of intestinal morphology. Biochemical studies, such as total lipid and phospholipid compositions, allowed us to have more detailed results. All identified mucosal phospholipids were modified, particularly the phosphatidylcholine (PC) and the phosphatidylethanolamine (PE) in the jejunum mucosa. In fact, there was a decrease by 55.81% for PC, 56.66% for PE, while a significant increase by 32.91% was noted for phosphatidylserine in the jejunum. It was very interesting to study the effect of OTA on the phospholipids layer of the bowel, as the mucous membrane of the small intestine represents the main site of absorption and transformation of nutriments. To avoid such disturbances and prevent the effects of the OTA, precautions must be taken to inhibit mold growth at the level of the feed manufactory units. Phosphatidylcholine and PE administrations may represent an option that could allow reestablishment of phospholipid equilibrium in the intestine.

Technology Development to Suppress the Campylobacter Jejuni in Intestinal Microflora of The Broilers by Lactobacilli

This article presents a method for determining the microflora of the blind processes of the intestines of broiler chickens receiving heterologous lactobacilli with anti-C.jejuni activity as a feed additive in comparison with intact chickens. In the course of a scientific and production experiment on the Cobb 500 cross broilers, an experiment was carried out to determine the total number of bacteria in the intestinal contents by quantitative PCR. Sequencing was performed on a MiSeq genomic sequencer (Illumina, Inc., USA) using the MiSeq Reagent Kit v3 kit (Illumina, Inc., USA). Data were obtained on the total number of bacteria and their taxonomic diversity. As a result of the studies, it was shown that the microflora of broilers throughout the entire maintenance period corresponded to the norm. The use of feed additives based on lactobacilli in general had a positive effect on the state of microflora of the blind processes of the intestine..

Molecular cloning, tissue distribution and the expression of cystine/glutamate exchanger (xCT, SLC7A11) in different tissues during development in broiler chickens.

The cystine/glutamate exchanger (xCT, SLC7A11) is a component of the system Xc amino-acid antiporter that is able to export glutamate and import cysteine into cells. The xCT amino acid exchanger has received a lot of attention, due to the fact that cysteine is an essential substrate for the synthesis of glutathione (GSH), an endogenous antioxidant in cells. The objective of this research was to clone the full-length cDNA of chicken xCT, and to investigate the gene expression of xCT in different tissues, including intestinal segments of broiler chickens during development. The full-length cDNA of chicken xCT (2,703 bp) was obtained from the jejunum by reverse transcription-PCR and sequenced. Homology tests showed that chicken xCT had 80.4%, 80.2%, and 71.2% homology at the nucleotide level with humans, cattle, and rats, respectively. Likewise, amino acid sequence analysis showed that chicken xCT protein is 86.4%, 79.3%, and 75.6% homologous with humans, cattle, and rats, respectively. Additionally, phylogenetic analysis indicated that chicken xCT genes share a closer genetic relationship with humans and cattle, than with rats. The chicken xCT protein has 12 transmembrane helixes, 6 extracellular loops, and 5 intracellular loops. The mRNA of xCT was detected in all tissues, including intestinal segments, in which the mRNA expression of xCT was significantly higher (P < 0.05) within the colon, compared to the jejunum and ileum. During development, a linear pattern of changes regarding the levels of the xCT mRNA was found, indicating that there was an abundance of xCT within the duodenum (P < 0.05). Furthermore, there were changes of the xCT mRNA abundance in the colon during development, which displayed linear and cubic patterns (P < 0.05). These results indicated that xCT is widely expressed both in intestinal segments, as well as other organs that are not associated with nutrient absorption. Further investigation is needed to characterize the functional relevance of xCT activity in oxidative stress and inflammation in the small intestine of broiler chickens.

Microstructure of the small intestine in broiler chickens fed a diet with probiotic or synbiotic supplementation.

The aim of the study was to determine the effect of dietary supplementation of a probiotic and a synbiotic on the morphometric parameters of the small intestine of broiler chickens. The experiment was conducted on three hundred sixty, one-day-old female Ross 308 chicks, which were randomly selected from 20,000 birds and divided into three treatment groups (n=120) with ten replicates per treatment. The control group (C) was fed a commercial diet, the probiotic group (PRO) was fed the same diet with an added 1% of the probiotic Lavipan® (Lactococcus lactis, Carnobacterium divergens, Lactobacillus casei, Lactobacillus plantarum and Saccharomyces cerevisiae), and the synbiotic group (SYN) was fed the commercial diet with an added synbiotic: 0.8% of the prebiotic RFO (extracted from lupin seeds) and 1% Lavipan®. According to the manufacturer's data, apart from the typical probiotic action,microorganisms contained in the preparation release anti-bacterial substances (hydrogen peroxide and bacteriocins) and, therefore, are antagonistic towards pathogenic bacteria present in the gut of animals. Supplementation took place in the first seven days of rearing, and all birds had ad libitum access to water and feed during the 42days of the experiment. On the last day, all birds were slaughtered and samples from three segments of the small intestine were taken. Villi area, height, width and crypt depth ratios were read using Multiscan software. Synbiotic supplementation increased the BWG of broilers from first to tenth day of rearing, compared to the control group. The PRO group had improved villi morphometric parameters of the duodenum. In the jejunum and ileum, both bioactive substances improved villus width and villus surface area. Crypts were deeper in the small intestine of birds supplemented with bioactive substances, which allows greater renewal of the villi. As expected, the intestinal morphometric parameters of broiler chickens benefited from bioactive substance supplementation.

Effect of piperine and quercetin alone or in combination with marbofloxacin on CYP3A37 and MDR1 mRNA expression levels in broiler chickens

After oral route of administration, drug absorption is unpredictable and is governed by various factors such as multi drug resistance-1 (MDR1) an efflux transporter and drug metabolizing enzymes (like CYP3A4, CYP3A37, CYP2D6) at intestine and liver. Naturally available phyto chemicals like piperine and quercetin as well as some floroquinolones are known to inhibit MDR1 and CYP3A37 activity and increases bioavailability of co-administered drugs. This study was carried out to investigate the effect of piperine and quercetin alone or in combination with marbofloxacin on CYP3A37 and MDR1 mRNA expression levels in liver and intestine of broiler chicken. After oral administration of piperine and quercetin for 3 consecutive days followed by with or without oral administration of marbofloxacin for 5 days, CYP3A37 and MDR1 mRNA expression levels were determined using quantitative real-time PCR. Total of 36 broiler chickens in seven individual groups were treated with different regimen and the mRNA expression levels at duodenum and liver were analyzed with apt statistical tools. After piperine and quercetin combined treatment with marbofloxacin, CYP3A37 mRNA expression levels were significantly down regulated by 20.57 (p = .034) and 25.95 (p = .003) folds; and MDR1 mRNA expression levels were also significantly down regulated by 11.33 (p = .012) and 33.59 (p = .006) folds in liver and duodenum, respectively. Down regulation of CYP3A37 and MDR1 mRNA in liver and duodenum indicate the combined pretreatment of piperine and quercetin may be useful for improving the pharmacokinetics of orally administered drugs which are substrates for CYP3A37 and MDR1.

Antibiotic Resistance of Escherichia Coli Isolated from Broiler Chickens

Abstract The purpose of this study was to detect the antibiotic resistance of forty-one Escherichia coli isolates from the intestinal contents of slaughtered broiler chickens using the disk diffusion method according to Kirby-Bauer. Mueller-Hinton agar plates were inoculated with 0.1 ml overnight broth cultures of individual E. coli isolates and the disks with the following concentrations of antibiotics were applied onto them: ampicillin (10 μg), cefotaxime (30 μg), gentamicin (10 μg), streptomycin (10 μg), azithromycin (15 μg), tetracycline (30 μg), ciprofloxacin (30 μg) and levofloxacin (3 μg). After the incubation at 37 °C for 16—18 hours, the inhibition zones were measured and interpreted in accordance with the Clinical and Laboratory Standard Institute (CLSI) zone diameter breakpoints. Almost all E. coli isolates showed resistance to tetracycline (92.68 %), most of them were resistant to gentamicin (75.61 %) and levofloxacine (70.73 %). Phenotypic resistance to tetracycline was further confirmed with the help of the Polymerase Chain Reaction (PCR) procedure focused on the presence of specific tet(A) and tet(B) genes. These genes were detected in all 41 E. coli isolates. On the contrary, E. coli isolates were highly susceptible to both azithromycin and streptomycin. In conclusion, the study highlighted the role of commensal E. coli bacteria isolated from the intestines of broiler chickens as an important reservoir of tetracycline resistance genes.

In vivo and in vitro protective effect of arginine against intestinal inflammatory response induced by Clostridium perfringens in broiler chickens

BackgroundNecrotic enteritis is a widespread disease in poultry caused by Clostridium perfringens. We previously reported that dietary arginine supplementation protected the intestinal mucosa of broiler chickens with necrotic enteritis, but the related protective mechanisms remain unclear. The in vivo trial was designed as a 2 × 2 factorial arrangement to evaluated the effects of arginine supplementation on inflammatory responses, arginine transporters, arginine catabolism and JAK-STAT signalling pathway in broiler chickens challenged with C. perfringens or without C. perfringens. Furthermore, we validated the in vivo results using intestinal epithelial cells of chicken embryos.ResultsC. perfringens infection markedly increased gut gross pathological and histopathological lesion scores, promoted liver C. perfringens invasion, reduced serum arginine levels, and elevated jejunal mucosal lysozyme activities (P < 0.05), but these effects were significantly reversed by arginine supplementation in vivo (P < 0.05). The challenge significantly increased serum procalcitonin levels, jejunal mucosal iNOS activities and jejunal IL-6, TGF-β3, cationic amino acid transporter (CAT)-1, and CAT-3 mRNA expression (P < 0.05), whereas arginine supplementation significantly reduced jejunal IFN-γ, IL-1β, IL-6, IL-10, TGF-β3, and CAT-3 mRNA expression (P < 0.05). Arginine supplementation significantly attenuated the C. perfringens challenge-induced increases in jejunal iNOS, arginase 2, arginine decarboxylase, arginine:glycine amidinotransferase, JAK1, JAK3, STAT1, and STAT6 mRNA expression (P < 0.05). The in vitro experiment showed that C. perfringens challenge markedly increased cellular cytotoxicity and the mRNA expression of IL-1β, IL-8, IL-10, CAT-1 and CAT-3 (P < 0.05), which were significantly reversed by 50 μmol/L and/or 400 μmol/L arginine pre-treatment (P < 0.05).ConclusionsArginine prevented C. perfringens challenge-induced circulated arginine deficiency, normalized intestinal arginine transport and catabolism, down-regulated JAK-STAT signalling pathway and attenuated the inflammatory response, which exerted protective effects on the intestine of broiler chickens.

Effect of level of inclusion of clove (&lt;i&gt;Syzygium aromaticum&lt;/i&gt;) powder in the diet on growth and histological changes in the intestines and livers of broiler chickens

The study was designed to evaluate the effects of different levels of clove ( Syzygium aromaticum ) powder in the diet on growth performance and histological changes of the livers and intestines of broiler chickens at 21 and 35 days old. Three hundred and thirty-six one-day-old Ross (308) broilers were allocated to eight treatments, namely: NC: negative control and unvaccinated; PC: positive control and vaccinated; and treatments T1, T2, T3, T4, T5 and T6 supplemented with different levels of clove powder (10, 20, 30, 40, 50 and 60 g clove powder/kg of diet, respectively) and all vaccinated. At 21 and 35 days old, eight birds/treatment were weighed, and samples from the livers and intestines were collected to evaluate morphological and histological changes. The results showed that higher levels of clove powder (T3 to T6) resulted in a gradual decrease in the live body weight of the birds at 21 and 35 days old. Relative liver weight increased in T5 and T6 at 35 days, but not at 21 days. A shorter small intestine was recorded in birds that received 50 and 60 g (T5 and T6) clove powder, while the proportional length of small intestinal parts did not show differences among treatments at 21 and 35 days old. The supplementation in the T3 toT6 groups resulted in a gradual decrease in intestinal weight at 21 days, but was not evident at 35 days. Villus height, villus surface area and villus crypt depth showed a gradual decrease from T1 to T6 at 35 days old. Also, gradual loss was recorded of the intestinal epithelium structure by necrotic enteritis on the wall of villi with an increased level of clove powder (< T2). These results indicated that 10 g clove powder per kg diet could be used to improve the growth rate without affecting the health of the liver and intestines of broilers. Keywords: Gallus domesticus , morphology, histomorphometric, digestive system, vaccine

Heat stress, Eimeria spp. and C. perfringens infections alone or in combination modify gut Th1/Th2 cytokine balance and avian necrotic enteritis pathogenesis

Information on the dynamics of the chicken immune system during bacterial or parasite challenge in the presence or absence of stressful situations may provide a better understanding of the complex mechanisms behind these diseases. Necrotic enteritis (NE) had been controlled previously by the proper use of antimicrobial agents; however, more recently, NE has reemerged in many countries. The imposed restrictions on antimicrobial use and/or the intensive productive programs implemented by producers are challenges the birds, leading to large host adaptive responses that in many instances are like those elicited by stressors. This study analyses the effects of heat stress on Th1/Th2 cytokine balance, pathological features, and Toll-like receptor expression in the small intestine of broiler chickens infected with Clostridium perfringens type A in the presence or absence of Eimeria spp. co-infection. This co-infection model was experimentally used because it reproduces the findings commonly observed in the field during avian NE. For this purpose, broiler chickens infected with C. perfringens and/or Eimeria spp. were reared in isolator chambers subjected or not to heat stress intermittently. It was observed that heat stress directs the expression of Th2-type cytokines, increases Toll-like receptor 4 expression in the intestine and reduces the disease severity induced by Eimeria spp. and C. perfringens infections alone or in combination, most likely as a consequence of stress-induced changes in brain-gut axis activity.

Effect of different cereal-based diets supplemented with multi-enzyme blend on growth performance villus structure and gene expression (SGLT1, GLUT2, PepT1 and MUC2) in the small intestine of broiler chickens

An experiment was conducted to evaluate the effect of corn, wheat and barley-based diets supplemented with COMBO® multi-enzyme (an enzyme blend with 1000 active unit of phytase and 480 active unit of glycanase per gram in form of powder) on physiological response of chickens. Growth performance (gain, feed intake, and feed conversion), villus structure (villus height, villus width, crypt depth) and expression of glucose and peptide transporters (SGLT1, GLUT2, PepT1) and mucin producer (MUC2) genes in the small intestine of chickens were measured. One-day old Ross 308 mixed broiler chickens (n = 625) were allocated to 5 treatments with 5 replicates, using a completely randomized design (CRD), statistical plan. The control diet produced the greatest live weight (2251.26 g) and the lowest live weight (2015.77 g), was for birds on the wheat diet (P < 0.01). Cumulative feed intake and the mean daily feed intake was the greatest for the barley + enzyme treatment (4392.37 g) and the lowest (4164.21 g) for the wheat treatment (P < 0.01). The birds of control diet had the lowest feed conversion (1.90), but wheat and barley diets had the highest value (2.06). The smallest crypt depth in the jejunum (95 μm) was associated with birds in the barley + enzyme treatment and the greatest crypt depth in the jejunum (116 μm) belonged to birds on the wheat treatment. Wheat and barley diets resulted in a reduced villus height but supplementation with a multi-enzyme blend resulted in an increased the villus height (P < 0.01). Barley and wheat treatments had the greatest expression of glucose transporter (1.85 and 1.78 for SGLT1, 1.80 and 1.72 for GLUT2 respectively), peptide transporter (2.82 and 2.50 for PepT1) and mucin producer (1.38 and 1.48 for MUC2) genes in the small intestine (P < 0.01). In conclusion, using economical diets of wheat and barley complement to a corn-soy based diet without multi-enzyme is likely to have adverse effects on growth performance, villus morphology, and gene expression of nutrient transporters in the small intestine.

Characterization of intestinal immune response to Clostridium perfringens infection in broiler chickens

ABSTRACTNecrotic enteritis toxin B (NetB)-producing Clostridium perfringens (CP) type A is the etiological agent of necrotic enteritis (NE) – an economically significant disease in broiler chickens. Understanding the immune response to CP infection in broiler chickens is becoming important to develop effective vaccines against NE. An experiment was conducted to determine the expression levels of selected cytokine genes in the intestine and cecal tonsil of CP-challenged broiler chickens. In a floor-pen housing, broiler chickens were randomly assigned to the following treatment groups: 1) bacitracin methylene disalicylate (BMD)-free control diet with no CP challenge (CX), 2) BMD-supplemented diet with no CP challenge (CM), 3) BMD-free control diet with CP challenge (PCX), or 4) BMD-supplemented diet with CP challenge (PCM). The establishment of CP infection was confirmed, with the treatment groups exposed to CP having a 1.5 to 2-fold higher CP levels (P < 0.05) compared to the non-exposed groups. On day 1 and 7 post-challenge, jejunal segments and cecal tonsils were collected from experimental chickens for quantitative real-time RT-PCR analysis to determine the expression levels of interleukin (IL)-1β, interferon-γ (IFN-γ), IL-2, IL-13, IL-17, IL-10, and transforming growth factor (TGF)-β genes. Levels of antibodies to CP recombinant proteins were also determined in the plasma of experimental chickens. Results indicated that on day 7 post-challenge, IL-1β (proinflammatory cytokine), IL-13 (Th2 cytokine), and IL-17 (Th17 cytokine) were upregulated (P < 0.05) in CP-challenged PCX and PCM treatments, compared to the unchallenged (control) CX and CM treatments. A reverse trend was observed for TGF-β (anti-inflammatory cytokine), while no change was observed in IFN-γ (Th1 cytokine). Levels of plasma antibodies (IgY) to CP recombinant proteins were higher in CP-challenged treatments (PCX and PCM; P < 0.05), compared to their corresponding controls (CX and CM). It was concluded that CP infection induced inflammatory response in the intestine of broiler chickens, and the mechanisms of inflammation are probably mediated via Th2 and Th17 cells.

Effects of Glutamine on Digestive Function and Redox Regulation in the Intestines of Broiler Chickens Challenged with Salmonella Enteritidis

ABSTRACT The aim was to investigate the effect of glutamine (Gln) on broilers challenged with Salmonella Enteritidis. 240 1-day-old birds were divided into four groups in a completely randomized design, each of which included 6 replicates with 10 birds per replicate. Group I served as the unchallenged, untreated control (CON). All birds in groups II (SCC) - IV were challenged with 2.0 × 104 CFU/mL of S. Enteritidis. Birds in group III and IV were treated with 0.5% (Gln 1) and 1.0% (Gln 2), respectively, of Gln. The results indicated that S. Enteritidis infection led to a decrease in the average body weight at d 7, 14, and 21 (p<0.05). Chickens fed the Gln showed improved average body weights in comparison with the SCC group (p<0.05). At d 4, 7, 14, and 21, the Gln groups increased digestive enzyme (trypsin, lipase and amylase (except the amylase activity of jejunum at d 14 and d 21)) activities in the intestine (p<0.05), superoxide dismutase (SOD) (at d 14 jejunum; except at d 4, ileum) and catalase (CAT) (at d 4, and d 21, jejunum; d 4, ileum) activity in the serum (except at d 14) and intestinal mucosa (p<0.05), and the mRNA expression of SOD, CAT and nuclear respiratory factor 2 (Nrf2) of the intestinal mucosa compared with the SCC group (p<0.05). These results suggest that Gln as a feed additive could be effective for reducing the detrimental effects of S. Enteritidis infection of broilers.

Morphological features and morphometric indices of the mucous membranes of different parts of the intestines of broiler chickens for feeding feeds with probiotic additive

The article presents the results of histological, histochemical searches and histomorphometric indices of villous height, depth of the crypt of the mucous membrane of the duodenum, jejunum and caecum of broiler chickens, fed a feed with probiotic additive «Probion forte» at a dose of 1 g/kg for 42 days in a row. The experiments were carried out on broiler chickens of the «Kobb-500» breed under vivarium conditions. Two experimental groups of broiler chickens were formed, with a body weight of 37–40 g, with 30 heads in each: First group was received feed with the probiotic «Probion forte» at a dose of 1 g/kg, and the second-control group, which was fed the main ration without the addition of any preparation. At 15, 30 and 42 days of the experiment, 10 chicks from each group were withdrawn from the experiment, an autopsy was carried out and samples from the duodenum, jejunum and the i caecum were taken, which were fixed in 10% neutral formalin solution, Carnoua and Buena liquid, followed by paraffin filling. Gisto-cutters were made, stained with hematoxylin-eosin, by Stidman and McManus. For the histological, histochemical, histomorphometric search of the mucous membrane of the duodenum, jejunum and caecum of chickens of the experimental group, It was established that the use of «Probion forte» in a dose of 1 g/kg with food for chicken broilers in the process of growth and development was contributed to: activation of the mitotic and synthesizing functions of cells, active hyperplastic and hypertrophic processes in the structural elements of the mucous membrane of the investigated sections of the intestines of broiler chickens, as a result of which was expressed by an increase in the height of the villi and the depth of the crypts. In the broiler chickens of the experimental group it was most likely increased the height of the villi in the duodenum at 15 and 42 days; in the jejunum, the probable increase in the height of the villi was noted at 15 and 30 days, and in the caecum - at 30 and 42 days of the experiment. At the same time, the height of columnar epitheliocytes, which was located on the villi of the jejunum of animals of the I group, was 31.5 μm and 24.9 μm in control. At the same time, active formation of mucus-like cells of the duodenum, jejunum and caecum, rich in glycosaminoglycans and glycoproteins, has been established, which contributed to the formation of a thick mucosal biofilm. The latter serves as a liquid phase in which the movement of cells is carried out, as well as an important barrier to the action of enzymes, pathogens and conditionally pathogenic microorganisms. An increase in the number of columnar epithelial cells and cello-like cells of the villi of the intestinal mucus was aimed at improving parietal digestion, absorption and enhancement of the protective function.

Age, phosphorus, and 25-hydroxycholecalciferol regulate mRNA expression of vitamin D receptor and sodium-phosphate cotransporter in the small intestine of broiler chickens

Four experiments were conducted in this study. Experiment 1 was carried out to examine mRNA expressions of nuclear vitamin D receptor (nVDR), membrane vitamin D receptor (mVDR), and type IIb sodium-phosphate cotransporter (NaPi-IIb) in the small intestine of broiler chickens. Experiments 2, 3, and 4 were implemented to evaluate effects of age, non-phytate phosphorus (NPP), and 25-hydroxycholecalciferol (25-OH-D3) on mRNA expressions of nVDR, mVDR, and NaPi-IIb in the duodenum of chickens. Results showed that mRNA expression levels of nVDR and NaPi-IIb were highest in the duodenum of 21-day-old broilers, lower in the jejunum, and lowest in the ileum. By contrast, no differences in mRNA expression levels of mVDR were detected among the duodenum, jejunum, and ileum. Age quadratically affected mRNA expressions of nVDR, mVDR, and NaPi-IIb in the duodenum and 25-hydroxylase in the liver of 7- to 42-day-old broilers, with the highest levels observed at 21 d of age. By contrast, age linearly decreased mRNA expression level of 1α-hydroxylase in kidneys. Dietary NPP levels quadratically affected mRNA expression levels of nVDR and mVDR in the duodenum and 25-hydroxylase in the liver of 21-day-old broilers. The highest mRNA expression levels of nVDR and mVDR and lowest mRNA level of 25-hydroxylase were observed at 0.55% NPP. mRNA expression level of NaPi-IIb linearly declined when dietary NPP levels increased from 0.25 to 0.65%. Addition of 12.5μg/kg of 25-OH-D3 increased mRNA expression level of 1α-hydroxylase in kidneys and those of nVDR, mVDR, and NaPi-IIb in the duodenum of broilers compared with birds fed the diet without 25-OH-D3. These data indicate that mRNA expressions of nVDR and NaPi-IIb are highest in the duodenum, and the greatest mRNA levels of nVDR, mVDR, and NaPi-IIb are observed at 21 d of age. Dietary NPP levels quadratically increase mRNA expressions of nVDR and mVDR but linearly decrease NaPi-IIb mRNA level. 25-OH-D3 up-regulates the above gene transcription.

Responses in digestibilities of macro-minerals, trace minerals and amino acids generated by exogenous phytase and xylanase in canola meal diets offered to broiler chickens

Atypical diets based on canola meal (584 g/kg) and dextrose, supplemented with phytase and xylanase individually and in combination, were offered to 120 male Ross 308 broiler chicks with six replicates for each of the four treatments. The objective was to determine the effects of phytase and xylanase on the apparent digestibility coefficients of macro-minerals, trace minerals and amino acids along the small intestine of broiler chickens. The combination increased phosphorus digestibility by a two-fold factor (0.694 versus 0.324), calcium digestibility by a three-fold factor (0.527 versus 0.178), increased zinc from -0.141 to 0.324 and increased sodium digestibility coefficients from -1.402 to -0.359 in comparison to the control diet. Similarly, phytase and xylanase in tandem generated better responses in the apparent ileal digestibility coefficients of amino acids. The enzyme combination significantly increased the digestibility of nine essential amino acids by from 5.47% (methionine) to 35.4% (threonine), and seven non-essential amino acids by from 13.9% (glutamic acid) to 32.9% (proline). The better responses in apparent ileal digestibilities of phosphorus, calcium, sodium, zinc and five other trace minerals in broiler chickens offered the combination diet was confounded by its higher enzyme recovery activities in comparison to the individual supplemented diets and the study may suggest that the inclusions of phytase and xylanase in tandem should be considered in diets containing canola meal for broiler chickens.

Assessment of biotoxicity of Cu nanoparticles with respect to probiotic strains of microorganisms and representatives of the normal flora of the intestine of broiler chickens.

Copper nanoparticle Cu (d = 55 ± 15nm) and CuO nanoparticles (d = 90 ± 10nm) were used in the studies (OOO Platina, Russia). Using the method of pure cultures, we extracted Lactobacillus, Enterococcus, and Enterobacterium from the intestines of broilers. Additionally, strains of Bacillus subtilis 10641 and Bifidobacterium were involved in probiotic strains. The data obtained in the course of the study testify to the insignificant biotoxicity of copper nanoparticles with respect to representatives of the genera Lactobacillus (30 to 15μg/ml) and Bifidobacterium (30μg/ml), with the most sensitive bacteria being the genus Lactobacillus, for which a concentration of 7.5μg/ml was subinhibitory. The second stage was the study using method of agar wells. In the course of the experiment, we obtained results confirming the data of the research by the serial dilution method. In this case, as in the first case, the data indicate the insignificant biotoxicity of copper nanoparticles in relation to representatives of the genera Lactobacillus and Bifidobacterium. We have studied the bioaccumulating ability of microorganisms of the studied metals. In all the studies carried out, as in the first series of experiments, representatives of the genera Lactobacillus and Bifidobacterium with the lowest bioaccumulative ability were the most sensitive to copper nanoparticles and were 3.1 and 8.2%, respectively. The use of nanoparticles as a component of the fodder additive in small concentrations does not adversely affect not only the probiotic strains, but also the main representatives of the normoflora (Lactobacillus, Enterococcus, and Enterobacterium) of the poultry, the positive effect of the copper nanoparticles being directly related to low level of dissociation of nanoparticles, since biologically active ions will be released much more slowly, thereby creating a prolonged effect of exposure.

Histopathological Injuries, Ultrastructural Changes, and Depressed TLR Expression in the Small Intestine of Broiler Chickens with Aflatoxin B₁.

To explore AFB1-induced damage of the small intestine, the changes in structure and expression of TLRs (Toll-like Receptors) in the small intestine of chickens were systematically investigated. Ninety healthy neonatal Cobb chickens were randomized into a control group (0 mg/kg AFB1) and an AFB1 group (0.6 mg/kg AFB1). The crypt depth of the small intestine in the AFB1 group was significantly increased in comparison to the control chickens, while the villus height and area were evidently decreased, as well as the villus:crypt ratio and epithelial thickness. The histopathological observations showed that the villi of the small intestine exposed to AFB1 were obviously shedding. Based on ultrastructural observation, the absorptive cells of small intestine in the AFB1 group exhibited fewer microvilli, mitochondrial vacuolation and the disappearance of mitochondrial cristae, and junctional complexes as well as terminal web. Moreover, the number of goblet cells in the small intestine in the AFB1 group significantly decreased. Also, AFB1 evidently decreased the mRNA expression of TLR2-2, TLR4, and TLR7 in the small intestine. Taken together, our study indicated that dietary 0.6 mg/kg AFB1 could induce histopathological injuries and ultrastructural changes, and depress levels of TLR mRNA in the chicken small intestine.

Histological and biochemical evaluation of supplementing broiler diet with β-hydroxy-methyl butyrate calcium (β-HMB-Ca).

Two hundred and sixteen day-old Ross-308 broiler chicks were allocated into 4 groups to study the impacts of different concentrations (0.0, 0.1, 0.15 and 0.2%) of β-hydroxy-methyl butyrate calcium (β-HMB-Ca), on values of tri-iodothyronin (T3) and tetra-iodothyronin (T4) hormones, liver enzymes [aspartate aminotransferase (AST) and alanine aminotransferase (ALT)], uric acid, peroxide, malondialdihyde (MDA), fatty acids and some histological parameters of small intestine (thickness of mucosa, height of villi, thickness of villi, depth of epithelial crypts and epithelial height). The biochemical results did not show any significant effect on T3 and T4 hormones and ALT while there was significant (P<0.01) decrease of AST in groups 2 and 3 and significant (P<0.05) decrease in uric acid in groups 2, 3 and 4 in comparison to control. In the liver, peroxide value (PV) and free fatty acids (FFA) were significantly (P<0.05 and P<0.01 respectively) decreased in groups 2 and 3 compared to control. The histological changes indicate significant values (P<0.05) in all parameters of duodenum in group 2 and 3, while those parameters of jejunum showed significant values (P<0.05) in most parameters of groups 2 and 4. In conclusion, the addition of β-HMB-Ca to the broiler diet from age 1 to 35 days has improved the levels of liver function enzymes and uric acid in the serum and lowered the parameters of oxidation in the liver with improved the maturity, performance and secretory activities of the small intestine in broiler chickens.