Gastrointestinal Maturation is Accelerated in Turkey Poults Supplemented with a Mannan-Oligosaccharide Yeast Extract (Alphamune)

Early intestinal development and mucin transcription in the young poult with probiotic and mannan oligosaccharide prebiotic supplementation

Alternative and adjunctive approaches to decreasing the use of dietary antibiotics are becoming popular areas of study. Supplemental probiotics (commensal microbes) and prebiotics (indigestible complex carbohydrates) are 2 dietary approaches to facilitating the intestinal colonization of beneficial bacteria to compete with potential pathogens, thus creating a healthy mucosal environment. The intestinal mucosa is composed of mucin glycoproteins, which play a key role in preventing the attachment of pathogenic bacteria. At hatch, the neonatal turkey intestine is relatively aseptic and vulnderable to bacterial colonization by both commensal and pathogenic microbes. In the current study, we determined the transcription of MUC2, the primary mucin protein produced by goblet cells within the small intestine, and we also measured intestinal morphology immediately post-hatch through d 11. Poults were fed a conventional starter diet, the starter diet supplemented with one of 2 commercial probiotics (A, B), or a commercial mannan oligosaccharide. MUC2 transcription increased from d zero to d 4 post-hatch (P< 0.05), but there was no effect of probiotic or prebiotic supplementation. Villus height and villus area both increased with Probiotic B and mannan oligosaccharide supplementation (P<0.05) and there was a significant d X treatment interaction effect for crypt depth (P=0.007). These results suggest that probiotic and prebiotic supplementation can positively alter the intestinal microenvironment.

Effect of lactulose supplementation on growth performance, intestinal histomorphology, cecal microbial population, and short-chain fatty acid composition of broiler chickens

This study investigated the effects of dietary lactulose supplementation on broiler growth performance, intestinal histomorphology, cecal microflora, and cecal short-chain fatty acid (SCFA) concentrations. A total of 245 one-day-old male broiler chickens were randomly assigned to 5 different treatments, with 7 replicates including 7 birds each. The birds received the same basal diet based on corn--soybean meal, and lactulose was included in the diet at 0, 0.2, 0.4, 0.6, or 0.8% at the expense of corn and/or soybean meal. The body weight gain (linear, P=0.027) and feed conversion (linear, P=0.003) from 0 to 21 d showed significant improvement as dietary lactulose was increased from 0.2 to 0.8%. However, dietary lactulose did not affect broiler performance at the end of the experiment (42 d). Furthermore, intestinal measurements and the goblet cell count of broilers fed a lactulose-containing diet differed from those of birds fed a diet that did not contain lactulose. In addition, a significant quadratic response in the Lactobacillus count (P≤0.001) was observed at 42 d on increasing the level of lactulose. The cecal coliform bacterial population was not affected by the dietary treatments. Supplementation with lactulose significantly increased the concentrations of acetate, propionate, butyrate, and total SCFA measured on d 7 and d 42. In conclusion, inclusion of lactulose in the diet can enhance broiler performance and intestinal morphology by selectively stimulating intestinal microflora and increasing cecal SCFA concentrations.

Improved health and growth of fish fed mannan oligosaccharides: potential mode of action

Nowadays, aquaculture industry still confronts several disease-related problems mainly caused by viruses, bacteria and parasites. In the last decade, the use of mannan oligosaccharides (MOS) in fish production has received increased attention due to its beneficial effects on fish performance and disease resistance. This review shows the MOS use in aquaculture with a specific emphasis on the effectiveness of the several MOS forms available in the market related to disease resistance, fish nutrition and the possible mechanisms involved. Among the main beneficial effects attributed to MOS dietary supplementation, enhanced fish performance, feed efficiency and pathogen protection by potentiation of the systemic and local immune system and the reinforcement of the epithelial barrier structure and functionality are some of the most commonly demonstrated benefits. These combined effects suggest that the reinforcement of the intestinal integrity and functionality, together with the stimulation of the innate immune system, are the primary mode of action of MOS in fish. However, the supplementation strategy related to the structure of the MOS added, the correct dose and duration, as well as fish species, size and culture conditions are determinant factors to achieve improvements in health status and growth performance.

Effect of dietary supplementation of prebiotics and probiotics on intestinal microarchitecture in broilers reared under cyclic heat stress

This study was designed to evaluate the effect of dietary supplementation of prebiotics, mannanoligosaccharides (MOS) and/or probiotics (LBP) on intraepithelial lymphocytes (IEL) count, goblet cells (GC) count and differentiation and intestinal micro-architecture in broilers reared under cyclic heat stress. Day-old broilers (n = 250) were randomly divided into five groups. Fifty birds were reared within the thermoneutral zone (TNZ). Remaining birds were subjected to cyclic heat stress from day 21 to 42 (35° C, 75% RH, 8 h/d). The birds were fed corn-soy-based basal diet or the same diet supplemented with 0.5% MOS (HS-MOS), or 0.1% LBP (HS-LBP), or their combination (HS-SYN). The birds were slaughtered on day 42. Tissue samples were collected from mid-duodenum, jejunum and ileum, and stained with haematoxylin and eosin or combined Alcian blue and PAS technique. All differences were considered significant at p < 0.05. The IEL count increased in all intestinal segments of the HS group compared with the TNZ group and decreased in all supplemented groups compared with the HS group. Compared with the TNZ, heat stress reduced villus height, crypt depth and surface area in duodenum and ileum, and increased crypt depth in ileum. Villus width decreased in duodenum and jejunum compared with the TNZ group. Supplementation of LBP, MOS and SYN reversed all these changes in duodenum, while only increased villus height and surface area in ileum. In jejunum, the villus height and surface area increased with HS-LBP, and crypt depth increased with HS-MOS. The number of GC containing acid mucins (duodenum and ileum) and mixed mucins (ileum) were increased in the HS compared with the TNZ. Supplementation of MOS, LBP and SYN maintained the enhanced activity of goblet cells. In conclusion, dietary supplementation of MOS and/or LBP may be helpful in alleviating some of the detrimental effects of heat stress on microstructure of the broiler gut.

Performance, histomorphology, and toll-like receptor, chemokine, and cytokine profile locally and systemically in broiler chickens fed diets supplemented with yeast-derived macromolecules

The turnover of intestinal epithelial cells is a dynamic process that includes adequate cell proliferation and maturation in the presence of microbiota and migration and seeding of immune cells in early gut development in chickens. We studied the effect of yeast-derived macromolecules (YDM) on performance, gut health, and immune system gene expression in the intestine of broiler chickens. One thousand eighty 1-d-old birds, with 60 birds per pen and 6 pens per treatment, were randomly assigned to 3 treatment diets; a diet containing monensin (control), control diet supplemented with bacitracin methylene disalycylate (BMD), and BMD diet supplemented with YDM. Feed intake, BW, mortality, ileum histomorphology, and gene expression of Toll-like receptors (TLR2b, TLR4, and TLR21), cytokines [interferon (IFN)-γ, IFN-β, IL-12p35, IL-1β, IL-6, IL-10, IL-8, IL-2, IL-4, and transforming growth factor (TGF)-β4], and cluster of differentiation (CD)40 in the ileum, cecal tonsil, bursa of Fabricius, and spleen were assessed. No significant overall difference in performance in terms of feed intake, BW gain, and G:F was observed among treatments (P > 0.05). The YDM diet resulted in significantly higher villi height and villi height:crypt depth ratio compared with BMD and control diets (P < 0.05). A significantly lower mortality was observed in the YDM treatment compared with both control and BMD treatments. Compared with the control, gene expression analysis in YDM treatment showed no major change in response in the ileum, whereas higher CD40, IFN-β, IL-β, IL-6, TGF-β4, IL-2, and IL-4 in the cecal tonsil; TLR2b, TLR4, TLR21, and TGF-β4 in the bursa of Fabricius; and TLR4, IL-12p35, IFN-γ, TGF-β4, and IL-4 in the spleen was observed (P < 0.05). In conclusion, supplementation of YDM supports pro- and anti-inflammatory cytokine production via T helper type 1 and 2 (Th1 and Th2) cell-associated pathways both locally and systemically with a stronger additive effect in the cecal tonsil in the presence of BMD in the diet of chickens.

Effect of ginger (Zingiber officinale Roscoe) on growth performance, nutrient digestibility, serum metabolites, gut morphology, and microflora of growing guinea fowl

A 56-day feeding trial was conducted to investigate the effect of dietary supplementation of dried ginger meal (DGM) on the growth performance, nutrient digestibility, serum parameters, gut morphology, and microflora of growing helmeted guinea fowl (Numidia meleagris). One hundred sixty 28-day-old male keets were assigned to four dietary treatments. There were 40 birds per treatment replicated four times with 10 keets each. The experimental diets consisted of the basal diet (control), ginger-supplemented diets containing 20, 40, and 60 g/kg DGM, respectively. Guinea fowls fed diet supplemented with DGM had higher (P <0.05) final body weight, body weight gain and lower (P <0.05) feed intake. Optimum weight gain was obtained with supplementation level of 36.15-g DGM (R (2) = 0.923). Guinea fowls fed diet supplemented with 40 g/kg DGM recorded the highest (P <0.05) coefficient of total tract apparent digestibility of dry matter, ether extract and longest (P <0.05) duodenal and ileal villus heights. The crypt depth of the duodenum and ileum reduced (P <0.05) with increasing level of dietary supplementation of DGM. Dietary supplementation of DGM resulted in increased (P <0.05) total serum protein, serum albumin and low (P <0.05) serum cholesterol concentration. Ileum content of birds fed diet supplemented with 40 g/kg DGM recorded the highest (P <0.05) lactobacillus count. In conclusion, dietary inclusion of 40-g DGM per kilogram diet is hereby recommended for improved growth, apparent nutrient digestibility, gut morphology, serum chemistry, and stimulation of balanced intestinal microflora in growing guinea fowl.

A natural carbohydrate fraction Actigen™ fromSaccharomyces cerevisiaecell wall: effects on goblet cells, gut morphology and performance of broiler chickens

A study was conducted to evaluate a natural carbohydrate fraction Actigen™ (NCF), derived from mannanoligosaccharide, in feed on growth performance, intestinal morphology and goblet cell number and area of male broilers'. Dietary treatments included: 1) control diet (antibiotic and NCF free), 2) NCF at 200 g/t, 3) NCF at 400 g/t, and 4) NCF 800 g/t. Two hundred and forty birds were placed into 12 replicate pens per treatment (5 birds/pen), sixty birds per treatment. Body weight and feed intake were recorded weekly up to day 42. At this time a 2.5cm section of jejunum and duodenum were excised post mortem for morphological analysis. Birds fed 200 g/t and 800 g/t NCF were significantly (P < 0.01) heavier from day 14 onwards than the control birds. Feed intake was significantly higher in birds fed 200 g/t NCF compared to those fed the control at 21 and 35 days (P < 0.05). Diets containing 200 g/t and 800 g/t of NCF significantly decreased broiler feed conversion ratio (FCR) compared to the control in the first phase (1–14 days) (P < 0.01) and levels of NCF decreased FCR (P < 0.05) in the second phase (15–28 days). NCF had no significant effect on villus height, villus width, crypt depth or villus to crypt ratio in either duodenum or jejunum. NCF did not significantly affect goblet cell area or goblet cell number in the duodenum, however, in the jejunum, 800 g/t NCF significantly (P < 0.05) increased goblet cell area over the control. In conclusion, NCF showed a positive effect on broiler performance in the starter and grower phases, and increased goblet cell area in the jejunum, suggesting higher levels of mucin production. This indicated that the performance benefit of NCF could be age-dependent, with younger birds responding more than the older ones. There were no additional benefits to performance when feeding NCF for a longer period (after 28 d of age), however it is postulated that birds fed NCF would have greater defence to pathogenic challenge through increased storage capacity of mucin.

β-1,3/1,6-Glucan alleviated intestinal mucosal barrier impairment of broiler chickens challenged with Salmonella enterica serovar Typhimurium

This study investigated the protective effect of β-1,3/1,6-glucan on gut morphology, intestinal epithelial tight junctions, and bacterial translocation of broiler chickens challenged with Salmonella enterica serovar Typhimurium. Ninety Salmonella-free Arbor Acre male broiler chickens were randomly divided into 3 groups: negative control group (NC), Salmonella Typhimurium-infected positive group (PC), and the Salmonella Typhimurium-infected group with dietary 100 mg/kg of β-1,3/1,6-glucan supplementation (T) to determine the effect of β-1,3/1,6-glucan on intestinal barrier function. Salmonella Typhimurium challenge alone significantly decreased villus height (P < 0.001), villus height/crypt depth ratio (P < 0.05), and the number of goblet cells (P < 0.001) in the jejunum at 14 d postinfection (dpi), but significantly increased the number of intestinal secretory IgA (sIgA)-expressing cells at 14 dpi (P < 0.01) and total sIgA levels in the jejunum at 7 (P < 0.05) and 14 dpi (P < 0.01) compared with the unchallenged birds (NC). Dietary β-1,3/1,6-glucan supplementation not only significantly increased villus height, villus height/crypt depth ratio, and the number of goblet cells (P < 0.01), but also increased the number of sIgA-expressing cells (P < 0.05) and sIgA content in the jejunum at 14 dpi (P < 0.01) in birds challenged with Salmonella Typhimurium in comparison with Salmonella Typhimurium challenge alone. β-1,3/1,6-Glucan addition had significant inhibitory effects (P < 0.05) on cecal Salmonella colonization levels and liver Salmonella invasion of the Salmonella Typhimurium-infected birds compared with the PC group. Intestinal tight junction proteins claudin-1, claudin-4, and occludin mRNA expression in the jejunum at 14 dpi was significantly decreased by Salmonella Typhimurium challenge alone (P < 0.01) compared with that of the NC group, whereas β-1,3/1,6-glucan supplementation significantly increased claudin-1 and occludin mRNA expression (P < 0.01) at 14 dpi in the jejunum of the Salmonella Typhimurium-infected birds in comparison with the PC group. Our results indicate that dietary β-1,3/1,6-glucan can alleviate intestinal mucosal barrier impairment in broiler chickens challenged with Salmonella Typhimurium.

Chronic exposure to the mycotoxin T-2 promotes oral absorption of chlortetracycline in pigs

The aim of this study was to investigate whether T-2 toxin, a potent Fusarium mycotoxin, affects the oral absorption of the antibiotic chlortetracycline in pigs. Animals were allocated to blank feed without T-2 toxin (controls), feed containing 111 μg T-2/kg feed, T-2-contaminated feed supplemented with a yeast-derived feed additive, or blank feed supplemented solely with the feed additive, respectively. After 21 days, an intragastric bolus of chlortetracycline was given to assess potential alterations in the pharmacokinetics of this commonly used antibiotic. A significantly higher area under the plasma concentration-time curve and maximal plasma concentration of chlortetracycline was observed after intake of T-2-contaminated feed compared with control. Thus, exposure to T-2-contaminated feed can influence the oral bioavailability of chlortetracycline. This effect could have consequences for the withdrawal time of the drug and the occurrence of undesirable residues in edible tissues.

Effect of yeast cell product (CitriStim) supplementation on broiler performance and intestinal immune cell parameters during an experimental coccidial infection

This experiment studied the effects of whole yeast cell product supplementation on broiler production parameters, fecal coccidial oocyst counts, and local and systemic immune parameters following an experimental coccidial infection. Birds were fed 0, 0.1, or 0.2% whole yeast cell product (CitriStim). At 21 d of age, birds were challenged with live coccidial oocysts. Supplementation with whole yeast cell product increased BW gain between 0 and 12 d (P = 0.01) postcoccidial challenge. Birds supplemented with 0.2% Citristim had better (P = 0.01) feed efficiency between 0 and 12 d postcoccidial infection. Supplementation with whole yeast cell product decreased (P = 0.01) the fecal coccidial oocyst count at 7 d postcoccidial challenge. Citristim supplementation at 0.2% increased (P < 0.01) macrophage nitric oxide production by 93 and 193% at 5 and 12 d postcoccidial challenge. Supplementation with whole yeast cell product at 0.2% increased cecal tonsil interleukin-1 mRNA amounts approximately 4.5- and 3.7-fold at 5 and 12 d postcoccidial challenge, respectively, over the group with no whole yeast cell product supplementation. Citristim supplementation downregulated cecal tonsil interleukin-10 mRNA amounts compared with the unsupplemented groups at both 5 (P = 0.01) and 12 d (P < 0.01) postcoccidial challenge. Supplementation with whole yeast cell product did not alter (P > 0.05) serum anticoccidial IgG contents or cecal tonsil CD4(+) and CD8(+) cell percentages at 5 and 12 d postcoccidial infection. It could be concluded that supplementing whole yeast cell product (CitriStim) to broiler diets can improve production parameters, decrease fecal oocyst count, and increase inflammatory cytokine production postcoccidial infection.

Efficacy and safety testing of mycotoxin-detoxifying agents in broilers following the European Food Safety Authority guidelines

Contamination of feeds with mycotoxins is a worldwide problem and mycotoxin-detoxifying agents are used to decrease their negative effect. The European Food Safety Authority recently stated guidelines and end-points for the efficacy testing of detoxifiers. Our study revealed that plasma concentrations of deoxynivalenol and deepoxy-deoxynivalenol were too low to assess efficacy of 2 commercially available mycotoxin-detoxifying agents against deoxynivalenol after 3 wk of continuous feeding of this mycotoxin at concentrations of 2.44±0.70 mg/kg of feed and 7.54±2.20 mg/kg of feed in broilers. This correlates with the poor absorption of deoxynivalenol in poultry. A safety study with 2 commercially available detoxifying agents and veterinary drugs showed innovative results with regard to the pharmacokinetics of 2 antibiotics after oral dosing in the drinking water. The plasma and kidney tissue concentrations of oxytetracycline were significantly higher in broilers receiving a biotransforming agent in the feed compared with control birds. For amoxicillin, the plasma concentrations were significantly higher for broilers receiving an adsorbing agent in comparison to birds receiving the biotransforming agent, but not to the control group. Mycotoxin-detoxifying agents can thus interact with the oral bioavailability of antibiotics depending on the antibiotic and detoxifying agent, with possible adverse effects on the health of animals and humans.

Effects of dietary yeast extract on turkey stress response and heterophil oxidative burst activity

1. Effective nutritional approaches to counteract the negative effects of stress may provide food animal producers with useful alternatives to antibiotics. In this study, turkeys were fed on a standard diet, or the same diet supplemented with yeast extract (YE), to determine if YE would improve disease resistance in a stress model. 2. At 16 weeks of age, half of the birds were exposed to a bacterial challenge using a coarse spray of the pen environment. A subset of control and challenged birds was also treated with dexamethasone (Dex) prior to challenge (Dex/challenge). At 18 weeks, another subset was subjected to a 12?h transport stress protocol (Challenge/transport). All birds were bled and necropsied the morning after transport. The numbers and proportions of blood cells and the heterophil oxidative burst activity (OBA) were determined. Serum corticosterone (Cort) levels of male birds were measured using a commercial ELISA kit. Body weight and gain were increased by YE during week 1. 3. YE decreased mortality and bacterial isolation following Dex/challenge only in females. Cort levels in male turkeys were decreased by YE and Dex treatment. OBA was higher in males and in birds given YE and was reduced by challenge and transport. 4. These results suggest there may be gender differences in the turkey stress response and that dietary YE has potential for modulating the impact of stress on innate immunity of turkeys.

Comparative efficacy of a yeast product and bacitracin methylene disalicylate in enhancing early growth and intestinal maturation in broiler chicks from breeder hens of different ages

The intestine of the newly hatched chick is immature at hatch. Yeast contains nucleotides and β-glucans that enhance intestinal development and chick growth. Accordingly, a 14-d experiment was conducted to evaluate the efficacy of a novel yeast product and bacitracin methylene disalicylate in enhancing early growth and intestinal maturation in chicks obtained from young (26-27 wk old) and old (58 to 59 wk old) breeder hens. Chicks (384) were randomly assigned to 8 dietary treatments. Treatment 1 (YH) consisted of chicks, from young hens, fed corn-soybean meal (SBM) diet alone. Treatment 2 (YHB) consisted of chicks, from young hens, fed corn-SBM basal into which BMD was added at 0.055 g/kg. Treatment 3 (YHE) consisted of chicks, from young hens, fed corn-SBM basal into which yeast extract (YE) was added at 0.075% level. Treatment 4 (YHED) consisted of chicks, from young hens, fed corn-SBM basal into which YE was added at 0.15% level. Treatments 5 (OH), 6 (OHB), 7 (OHE), and 8 (OHED) consisted of chicks from old hens fed diets similar to those given to YH in treatments 1, 2, 3, and 4, respectively. Growth performance (body weight gain and feed conversion ratio) was evaluated on d 7 and 14. Intestinal tissue samples were also analyzed for alkaline phosphatase (ALP) activity as an indicator of intestinal maturation on d 4 and 13 of experiment. Results showed that by d 14 of experiment, only BMD treatments (YHB and OHB) improved body weight gain (P < 0.05). However, the body weight gains of chicks in the yeast-supplemented treatments (YHE, YHED, OHE, and OHED) were statistically similar (P > 0.05) to those of the BMD treatments. Ileal ALP activity was consistently enhanced by BMD and yeast product supplemented at 0.075% of the diet. It was concluded that antibiotic BMD and our novel yeast product supplemented at 0.075% of the diet improved early chick growth and maturation of the ileal segment of the small intestine.

Reduced gut bacterial translocation in European sea bass (Dicentrarchus labrax) fed mannan oligosaccharides (MOS)

The objective of this study was to determine the effect of mannan oligosaccharides derived from the outer cell wall of a select strain of Saccharomyces cerevisiae (Bio-Mos, Alltech Inc, USA) on mucus production, selected mucus immune parameters activity, gut morphology and in vivo and ex vivo gut bacterial translocation for European sea bass (Dicentrarchus labrax). Specimens were fed 4 g kg⁻¹ dietary MOS level of inclusion in a commercial sea bass diet for eight weeks. At the end of this period, anterior gut mucosal folds height, width and folds surface area were increased by MOS supplementation (P < 0.05, n = 240). Posterior gut presented shorter folds (P < 0.05, n = 240) but wider that those fed control diet (P < 0.05, n = 240) resulting in increased total surface area (P < 0.05, n = 240). For rectum, feeding MOS reduced fold length (P < 0.05, n = 240). Gut morphological analyses showed an enhancement in the number of cells secreting acid mucins by area unit, higher density of eosinophilic granulocytes (ECGs) in the mucosa for fish fed MOS together with an improvement in gut mucus lysozyme activity which could be related to the reduced in vivo and ex vivo gut bacterial translocation found. No differences were found for the skin mucus immune parameters evaluated.

Characterisation and response of intestinal microflora and mucins to manno-oligosaccharide and antibiotic supplementation in broiler chickens

1. An experiment was conducted to characterise and evaluate, in comparison to zinc bacitracin (ZnB), the response of intestinal microflora and mucins to manno-oligosacchares (MOS, Bio-MOS(R), Alltech Biotechnology, Nicholasville, Kentucky, USA). 2. Supplementation of MOS and ZnB selectively increased the intensity of sulphomucins. As revealed by the plate culture method, MOS accelerated the maturation of gut microflora by promoting the growth of lactobacilli in the ileal mucosa and vice versa on ileal and caecal clostridia. Unlike MOS, ZnB suppressed the growth of intestinal bacteria, especially those of lactobacilli and clostridia. Use of T-RFLP further revealed that MOS increased the diversity of lactobacilli in the ileum and ileal mucosa but the opposite was observed for ZnB. It also appears that MOS and ZnB possessed a common property in differentially favouring the growth of certain Lactobacillus species. There was also evidence to show that both MOS and ZnB also increased the homogeneity of the gut microflora, possibly through the regulation of the overall gut bacterial communities. 3. Improvement in intestinal microbial homogeneity and mucin synthesis, coupled with the differential selections for certain specific beneficial bacterial species, may ultimately be proven to be the target mechanisms in the search for more effective alternatives to antibiotics.

Evaluation of the efficacy of yeast extract in reducing intestinal Clostridium perfringens levels in broiler chickens

The etiological agent of necrotic enteritis is Clostridium perfringens. Traditionally, necrotic enteritis is controlled with in-feed antibiotics. However, increasing consumer demand for drug-free poultry has fostered the search for nonantibiotic alternatives. Yeast extract contain nucleotides that are immunomodulatory and also essential for cellular functions. An experiment was conducted to evaluate the efficacy of NuPro yeast extract (Alltech Inc., Nicholasville, KY) in reducing intestinal C. perfringens levels in broiler chickens. One hundred ninety-two 1-d-old male broiler chicks were obtained and randomly assigned to 6 treatments in a battery cage trial. Treatment 1 consisted of chicks fed a corn-soybean meal basal diet (BD) without added bacitracin methylene disalicylate or NuPro. Treatment 2 consisted of chicks fed BD into which bacitracin methylene disalicylate was added at 0.055 g/kg. Treatment 3 consisted of chicks fed BD supplemented with NuPro at a 2% level for the first 10 d of the experiment. Treatments 4 (PX), 5, and 6 (PN) consisted of chicks that were challenged with 3 mL of the C. perfringens inoculum (~10(7) cfu/mL) on d 14, 15, and 16 of the experiment and fed diets similar to treatments 1, 2, and 3, respectively. On d 1 and 7 postchallenge, intestinal C. perfringens levels, lesion scores, and alkaline phosphatase activity were assessed. On d 1 postchallenge, C. perfringens level in treatment 5 (2.09 log(10) cfu/g) was lower (P < 0.05) compared with the PX treatment (4.71 log(10) cfu/g) but similar to the PN treatment (2.98 log(10) cfu/g). A similar trend was observed on d 7 postchallenge. NuPro supplementation enhanced alkaline phosphatase activity (P < 0.05) in C. perfringens-challenged chicks and appeared to reduce intestinal lesion scores. Although dietary supplementation of NuPro in the PN treatment reduced C. perfringens levels by 1.73 and 0.68 log(10) cfu/g compared with the PX treatment on d 1 and 7 postchallenge, respectively, these reductions were not significant. Extending the period of NuPro supplementation beyond the first 10 d of life should be considered for achieving significant reduction in intestinal C. perfringensg levels.

Intestinal villus histological alterations in broilers fed dietary dried fermented ginger

To evaluate the effect of dietary dried fermented ginger (DFG) on intestinal villous histological alteration and growth performance, 64 Marshall Chunky male broilers were divided into four groups, each with four replicates of four chickens. Birds were fed the basal commercial mash diet supplemented with DFG at 0 (control), 5, 10 and 20 g/kg for 42 days. With increasing dietary DFG levels, feed intake tended to decrease and significantly decreased in the 20 g/kg DFG group (p < 0.05). Weight gain was higher in all the DFG groups, with the highest in the 10 g/kg DFG group (p < 0.05), resulting in an improved feed efficiency in all the DFG groups. Intestinal villus height, villus area, cell area and cell mitosis in all the intestinal segments were higher in all the DFG groups than in the control group. Protuberated cells and cell clusters were found in all the DFG groups, suggesting that the intestinal villi and cells might be hypertrophied. The present results indicate that dietary DFG can be used as a natural feed additive to induce broiler growth performance as a result of stimulation of morphological maturation and in consequence intestinal function.

Bacterial clearance, heterophil function, and hematological parameters of transport-stressed turkey poults supplemented with dietary yeast extract

Yeast extracts (YE) contain biological response modifiers that may be useful as alternatives to antibiotics for controlling pathogens in poultry production and mitigating the deleterious effects of production stressors. The objective of the present study was to determine the ability of a commercial dietary YE (Alphamune) to modulate the immune response in male turkey poults challenged with Escherichia coli and subjected to transport stress. Alphamune was added to turkey poult diets at 0, 500, or 1,000 g/ton. Poults were challenged by air sac injection with 60 cfu of E. coli at 1 wk of age. At 3 wk of age, these challenged birds were subjected to transport stress and birds were bled and necropsied the following morning. Blood cell numbers and percentages, hematological parameters, and clinical chemistry values were determined. Oxidative burst activity of isolated heterophils was measured using stimulation with phorbol myristate acetate and a 2',7'-dichlorofluorescein diacetate assay. Data were analyzed using GLM and least squares means procedures of the SAS program. The numbers and percentages of heterophils in peripheral blood were increased and their oxidative burst activity was stimulated by YE. The stress challenge dramatically increased oxidative burst and this increase was significantly modulated by YE treatment. Serum levels of calcium, phosphorus, and triglycerides were decreased and uric acid levels, erythrocyte numbers, hemoglobin, and hematocrit were increased by YE supplementation. Bacteria were isolated from the air sac and liver of a lower percentage of birds provided with YE. These results suggest that dietary YE has potential as a nonantibiotic alternative for decreasing bacterial pathogens in turkey production.

Indigestible carbohydrates alter the intestinal microbiota but do not influence the performance of broiler chickens

AIMS

Prebiotics are a potential alternative to in-feed antimicrobials to improve performance of chickens. We investigated the effects of mannanoligosaccharide (MOS) and fructooligosaccharide (FOS) on growth, performance and the intestinal microbiota.

METHODS AND RESULTS

Cobb 500 birds were fed either: Control, starter diet without antimicrobials; ZnB, Control + 50 ppm zinc bacitracin; MOS, Control + 5 g kg(-1) MOS; or FOS, Control + 5 g kg(-1) FOS. An energy metabolism study was conducted and intestinal microbial communities assessed by T-RFLP and Lac PCR-DGGE. Diet did not influence performance. Ileal microbial communities were significantly different in ZnB-fed birds compared to all diets, and FOS-fed chickens compared to Control. MOS-fed chickens had a different caecal profile to ZnB and FOS-fed birds. Consensus Lac PCR-DGGE profiles indicated Lactobacillus communities clustered according to diet with Lactobacillus johnsonii characteristic of ZnB diet. Control and MOS-fed chickens displayed significantly different jejunal Lactobacillus profiles to each other whilst ileal profiles were different between MOS and FOS-fed birds.

CONCLUSION

Prebiotics influenced the intestinal microbiota, but did not affect performance.

SIGNIFICANCE AND IMPACT OF THE STUDY

In light of pressure for in-feed antimicrobial withdrawal, the impact of alternative compounds on the intestinal microbiota and bird performance is critical to the poultry industry.

Therapeutic supplementation of caprylic acid in feed reduces Campylobacter jejuni colonization in broiler chicks

Poultry colonized with Campylobacter species are a significant source of human food-borne illness. The therapeutic use of the medium chain fatty acid caprylic acid consistently reduced enteric C. jejuni colonization in chicks by 3 to 4 logs in three separate trials. These results support caprylic acid's potential to reduce Campylobacter carriage in poultry.