Effects of feed form and dietary coarse ground corn on broiler live performance, body weight uniformity, relative gizzard weight, excreta nitrogen, and particle size preference behaviors.

In this 14-d cage study, the effects of feed form (mash and crumble) and 6 coarse ground corn ( CC: ) inclusions [0, 10, 20, 30, 40, and 50% CC that replaced fine corn ( FC: )] on broiler live performance, BW uniformity, gizzard weight, excreta nitrogen, and particle size preference were investigated. The geometric mean diameter by mass ( DGW: ) of mash diets increased from 422 µm to 431, 471, 509, 542, and 640 µm, respectively, as the percentage of CC increased. Feed intake and BW were decreased by CC and mash at 7 d. Interactions between feed form and CC were observed for feed conversion ratio ( FCR: ) at 7 d of age (P < 0.01), and feed intake (P < 0.05), BW (P < 0.01), and gizzard weight (P < 0.01) at 14 d of age. Feed intake for all CC inclusions in crumble diets was similar and exceeded (P < 0.01) that of mash diets at 14 d. Among mash diets, the 10 and 30% CC feed intake was greater (P < 0.05) than 40 and 50% CC with 0 and 20% CC intermediate. Crumble diets produced a similar BW but greater 14-d BW than mash diets (P < 0.01). Within mash diets, 40 and 50% CC produced a smaller BW (P < 0.01). The FCR at 7 d of CC inclusions in crumble diets was improved (P < 0.01) versus the same CC in mash diets. Within mash diets, 40% CC performed poorer than 0, 10, 20, and 30% CC diets with 50% CC diet intermediate (P < 0.01). Crumble diets improved FCR at 14 d, but CC worsened FCR. Gizzard weight at 14 d was not affected by CC in crumble diets, while it increased with CC in mash diets (P < 0.01). Excreta nitrogen was increased (P < 0.01) by crumble diets. These data demonstrated that pelleting and crumbling reduced the impact of CC, produced a more consistent feed intake, and reduced selective feeding, and that CC stimulated gizzard weight in a linear manner in mash diets.

Effect of dietary coarsely ground corn on broiler live performance, gastrointestinal tract development, apparent ileal digestibility of energy and nitrogen, and digesta particle size distribution and retention time.

Dietary structural material has been reported to improve broiler live performance and gastrointestinal tract (GIT) function. In this 50 d cage study, the effects of coarsely ground corn (CC) inclusion on broiler live performance, GIT development, apparent ileal digestibility (AID) of energy and nitrogen (N), and digesta particle size distribution and retention time were investigated. This study included 3 CC inclusions (0, 25, and 50% fine corn [FC] replaced by CC), with 6 replicate cages of 10 birds per treatment. The feed conversion ratio (FCR) at 35 and 42 d was improved (P<0.01) as the dietary inclusion of CC increased without effect on feed intake. The 50% CC diet increased absolute and relative gizzard weight at 42 d of age as compared to diets with 0 and 25% CC (P<0.01). Dietary CC increased absolute proventriculus weight at 28 d of age (P<0.05). A numerically lower gizzard digesta pH (P<0.08) was observed at 28 d but not 42 d of age, and there was no difference in proventriculus, jejunum, or ileum digesta pH at 28 or 42 d of age. The 25 and 50% CC treatments increased the digesta retention time at 30 and 45 d of age (P<0.05 and P<0.01, respectively). The 25 and 50% CC treatments improved AID of energy by 7.1 and 8.2%, respectively, when compared with the 0% CC treatment, and they improved AID of N by 12.2 and 12.4%, respectively (P<0.01). The digesta particles in the jejunum exhibited a similar distribution, with a dgw (geometric mean diameter by mass) of 218, 204, and 181 µm when 0, 25, of 50% CC diets were consumed, respectively. In conclusion, birds fed pelleted and screened diets that contained 25 and 50% CC exhibited increased BW, improved FCR, and increased AID of energy and N, which was probably due to enhanced gizzard development and greater digesta retention time.

Effects of dietary coarsely ground corn and litter type on broiler live performance, litter characteristics, gastrointestinal tract development, apparent ileal digestibility of energy and nitrogen, and intestinal morphology.

The objectives of this study were to evaluate the effects of the dietary inclusion of 2 coarsely ground corn (CC) levels (0 or 50%) in diets of broilers reared on 2 litter types (new wood shavings or used litter) on live performance, litter characteristics, gastrointestinal tract (GIT) development, apparent ileal digestibility (AID) of energy and nitrogen (N), and intestinal morphology. No interaction effects between CC level and litter type were observed on live performance. No litter effect was observed on live performance. Dietary inclusion of 50% CC increased BW at 35 d (P<0.01) and improved cumulative feed conversion ratio (FCR) at 35 and 49 d of age (P<0.01). The 50% CC treatment increased absolute and relative gizzard weight (P<0.01) and decreased jejunum unit weight (g/cm) (P<0.01). The new litter treatment (litter N) increased absolute and relative proventriculus weight (P<0.05) but did not affect gizzard weight. An interaction effect between CC level and litter type was observed for litter N, where the 50% CC treatment reduced litter N regardless of litter type (P<0.01), but litter N was reduced by new litter only among birds fed 0% CC (P<0.05). The 50% CC inclusion increased litter pH (P<0.05) and improved the AID of energy and N by 6.8% (P<0.01) and 3.5% (P<0.05), respectively. The 50% CC treatment increased jejunum villi tip width (P<0.05) and villi surface area (P<0.01), and decreased the muscularis layer thickness (P<0.01), whereas new litter increased jejunum villi and ileum villi height (P<0.05), jejunum villi surface area (P<0.01), and the ratio of jejunum villi height to crypt depth (P<0.01). This study showed that birds fed pelleted and screened diets containing 50% CC exhibited improved BW, FCR, and AID of energy and N, in conjunction with altered morphology of the GIT and intestinal mucosa. Litter type affected some GIT traits and functions but did not affect live performance.

Evaluation of litter type and dietary coarse ground corn inclusion on broiler live performance, gastrointestinal tract development, and litter characteristics.

Two 49 d floor pen studies were conducted to evaluate the effects of litter type and dietary coarse ground corn (CC) inclusion on broiler live performance, gastrointestinal tract (GIT) development, and litter characteristics. Experiment 1 was a 2×2 factorial arrangement of 2 genders (male or female) and 2 CC levels (0 or 50%). From 15 to 35 d, the addition of CC decreased feed intake (P<0.01) and BW gain (P<0.05) of males but not females. The inclusion of CC decreased feed intake (P<0.01) and BW gain (P<0.01) from 0 to 49 d but improved adjusted feed conversion ratio (AdjFCR) from 35 to 49 d (P<0.05). Male broilers exhibited better live performance than females during the study as evidenced by greater feed intake (P<0.01) and BW gain (P<0.01), and improved FCR (P<0.01), but with increased mortality (P<0.05). The inclusion of CC increased relative gizzard weight (P<0.01) and decreased relative proventriculus weight (P<0.01) at 49 d. Experiment 2 was a 2×2 factorial arrangement of 2 CC levels (0 or 50%) and 2 litter types (ground old litter or new wood shavings litter). The inclusion of CC decreased feed intake throughout the experiment without affecting final BW when only males were used and improved FCR after 25 d (P<0.01). New litter improved FCR from 1 to 14 d (P<0.01). At 49 d, the birds fed the CC diet had reduced excreta nitrogen (P<0.05) and litter moisture (P<0.05). In conclusion, 50% CC inclusion initially produced negative effects on live performance that became positive as BW increased. The effects of CC became evident at an earlier age for males. New litter had only a marginal benefit on broiler live performance.

Effects of trypsin inhibitor and particle size of expeller-extracted soybean meal on broiler live performance and weight of gizzard and pancreas.

Soybean meal (SBM) is a co-product that remains after the oil is removed from whole soybeans by either solvent extraction or mechanically pressing soybeans using an expeller. Expeller-extracted soybean meal (ESBM) contains more fat and less protein than solvent-extracted soybean meal (SSBM), but has higher trypsin inhibitors (TI) that limit its inclusion in poultry diets. We hypothesized that increasing the particle size of ESBM could enhance chick tolerance to dietary TI. The experiment consisted of a 2 × 6 factorial arrangement of 2 ESBM particle sizes (coarse, 1,300 µm, and fine, 530 µm) and 6 TI levels (6, 9, 12, 15, 18, and 21 TIU/mg). A total of 672 male broiler chicks was randomly assigned among the 12 treatment combinations with 8 replicates per combination. The birds were provided with 1 kg/bird of starter diet in a crumble form. The pancreas and gizzard were excised and weighed at 16 d of age and organ weights relative to BW calculated. Feed consumption, BW, and feed conversion ratio (FCR) were determined at 7 and 14 d of age. Increasing TI level produced a quadratic effect (P < 0.01) on BW and FCR at 14 d of age. The best performance was obtained when chicks were fed diets containing ESBM at intermediate TI levels. Increasing the particle size of the ESBM from 530 to 1,300 µm improved BW and feed intake (P < 0.01) without affecting FCR. The relative weight of the pancreas increased linearly as TI level increased (P < 0.001). The results of this study indicated that chicks performed better when fed coarse ESBM at an intermediate TI level.

Effects of Clostridium butyricum on growth performance, immune function, and cecal microflora in broiler chickens challenged with Escherichia coli K88.

This study was conducted to investigate the effects of Clostridium butyricumon growth performance, immune function, and cecal microflora in broiler chickens challenged with Escherichia coli K88. Three hundred sixty 1-d-old broiler chickens were randomly divided into 4 treatments: negative control (NC) birds were fed a basal diet and not challenged with E. coli K88; positive control (PC) birds were fed a basal diet and challenged with E. coli K88; C. butyricum treatment (CB) birds were fed a diet containing 2 × 10(7) cfu C. butyricum/kg of diet and challenged with E. coli K88; and colistin sulfate treatment (CS) birds were fed a diet containing 20 mg of colistin sulfate/kg of diet and challenged with E. coli K88. Birds fed CB had greater (P < 0.05) BW than the PC birds from 3 to 21 d postchallenge. Birds fed CB had greater (P < 0.05) serum IgA and IgY at 14 d postchallenge, greater (P < 0.05) serum IgM at 21 d postchallenge, and greater (P < 0.05) mucosal secreted IgA at 3 and 7 d postchallenge than the PC birds. Birds fed CB had greater concentrations of serum complement component 3 at 14 d postchallenge, and greater (P < 0.05) concentrations of serum complement component 4 at 3, 7, and 14 d postchallenge than the PC birds. Birds in the CS or CB treatments had less cecal E. coli population at 3, 7, and 21 d postchallenge, and less cecal Clostridium perfringens counts at 21 d postchallenge compared with the PC birds. The CB treatment increased (P < 0.05) the population of cecal Lactobacillus at 3 d postchallenge and the number of cecal Bifidobacterium at 3, 14, and 21 d postchallenge in comparison with the PC treatment. The results indicate that dietary supplementation of CB promotes growth performance, improves immune function, and benefits the cecal microflora in Escherichia coli K88-challenged chickens.

Evaluation of soybean meal source and particle size on broiler performance, nutrient digestibility, and gizzard development.

Although there have been several reports concerning the effects of particle size of cereal grains on productive performance of poultry, there is limited information about the effects of soybean meal (SBM) particle size on broiler performance. The objective of the present experiments was to evaluate the effects of SBM source and particle size on broiler performance, gizzard weight, and nutrient digestibility. The first experiment was a 2 × 2 factorial arrangement of 2 SBM sources: expeller-extracted (ESBM) and solvent-extracted (SSBM), and 2 particle sizes: coarse grind, 971 µm, and fine grind, 465 µm. The second experiment was a 2 × 2 factorial arrangement of 2 ESBM particle sizes: coarse grind, 1,290 µm, and fine grind, 470 µm, and 2 corn particle sizes: coarse grind, 1,330 µm, and fine grind, 520 µm. In the first experiment, there was an interaction (P < 0.05) between SBM source and particle size on BW at 49 d of age. No differences in BW were observed when birds were fed coarse SSBM or ESBM, whereas birds fed diets containing fine ESBM exhibited lower BW than birds fed diets containing fine SSBM. In the second experiment, fine-grind ESBM (P < 0.05) and corn (P < 0.01) produced greater 19-d BW than did coarse grind. A significant interaction (P < 0.01) between ingredient type and particle size revealed that chicks fed coarse particles of corn or ESBM exhibited higher protein digestibility compared with chicks fed only fine particles. Corn particle size had a greater effect on gizzard weight than ESBM particle size. Birds fed diets that contained coarse corn had larger gizzards than birds fed fine corn (P < 0.01), but differences in gizzard weight were not observed when birds were fed coarse or fine ESBM. Particles greater than 1,300 µm depressed BW but improved protein digestibility.

Metabolic profiling of late-term turkey embryos by microarrays.

The last stages of embryonic development are crucial for turkeys as their metabolism shifts to accommodate posthatch survival and growth. To better understand the metabolic change that occurs during the perinatal period, focused microarray methodology was used to identify changes in the expression of key genes that control metabolism of turkey embryos from 20 d of incubation (E) until hatch (E28). Gene expression patterns were evaluated in liver, pectoral muscle, and hatching muscle and were associated with measured embryonic growth and tissue glycogen concentration. Within the studied period, the expression of 60 genes significantly changed in liver, 53 in pectoral muscle, and 51 in hatching muscle. Genes related to lipid metabolism (enoyl-CoA hydratase, 3-hydroxyacyl-CoA dehydrogenase, 3-hydroxymethylglutaryl-CoA reductase, acetyl-CoA carboxylase, lipoprotein lipase, and thyroxine deiodinase) had reduced expression between E22 and E26, corresponding to the period of expected limited oxygen supply. In contrast, genes related to opposing pathways in carbohydrate metabolism, such as glycolysis and gluconeogenesis (hexokinases, glucose-6 phosphatase, phosphofructokinases, glucose 1-6 phosphatase, pyruvate kinase, and phosphoenolpyruvate carboxykinase), or glycogenesis and glycogenolysis (glycogen synthase and glycogen phosphorylase) had rather static expression patterns between E22 and E26, indicating their enzymatic activity must be under posttranscriptional control. Metabolic survey by microarray methodology brings new insights into avian embryonic development and physiology.

By-product of Tropical Vermicelli Waste as a Novel Alternative Feedstuff in Broiler Diets.

Two experiments were conducted to determine physical and chemical properties of vermicelli waste (VW) and effect of VW inclusion levels on growth performance of broilers. In experiment 1, VW samples were randomly collected from vermicelli industry in Thailand to analyze nutritional composition. Vermicelli waste contained 9.96% moisture, 12.06% CP, 32.30% crude fiber (CF), and 0.57% ether extract (EE), as DM basis. The ratio of insoluble:soluble non-starch polysaccharide (NSP) was 43.4:8.9. A total of 120 chicks (6 pens per treatment and 10 chicks per pen) were fed a corn-soybean meal-based diet or 20% VW substituted diet to determine the apparent metabolizable energy corrected for nitrogen retention (AMEn) of VW. The AMEn of VW was 1,844.7±130.71 kcal/kg. In experiment 2, a total of 1,200 chicks were randomly allotted to 1 of 4 dietary treatments for 42-d growth assay. There were 300 chicks with 6 pens per treatment and 50 chicks per pen. The dietary treatments contained 0%, 5%, 10%, or 15% VW, respectively. All diets were formulated to be isocaloric and isonitrogenous. From 0 to 18 d of age chicks fed VW diets had higher (p<0.001) feed conversion ratio (FCR) compared with those fed the control diet. No difference was observed during grower and finisher phase (19 to 42 d). Chicks fed VW diets had lower relative weight of abdominal fat (p<0.001) but higher relative weight of gizzard (p<0.05) than those of chicks fed the control diet. Increasing VW inclusion levels increased ileal digesta viscosity (p<0.05) and intestinal villus height of chicks (p< 0.001). For apparent total tract digestibility assay, there were 4 metabolic cages of 6 chicks that were fed experimental treatment diets (the same as in the growth assay) in a 10-d total excreta collection. Increasing VW inclusion levels linearly decreased (p<0.05) apparent total tract digestibility of DM and CF.

Effects of probiotic, Clostridium butyricum, on growth performance, immune function, and cecal microflora in broiler chickens.

Four hundred and fifty 1-d-old male Lingnan Yellow broiler chickens were used to investigate the effects of Clostridium butyricum on growth performance, immune function, and cecal microflora. The birds were randomly assigned to 5 treatments and offered the same antibiotic-free basal diets for 42 d. The treatments were as follows: no addition (control), 1 × 10(7) cfu C. butyricum/kg of diet (CB1), 2 × 10(7) cfu C. butyricum/kg of diet (CB2), 3 × 10(7) cfu C. butyricum/kg of diet (CB3), and 10 mg of colistine sulfate/kg of diet (antibiotic). Birds fed either CB2 or antibiotic had greater overall BW than those in the control group. During d 1 to 7, d 21 to 42, and d 1 to 42, birds fed either CB2 or CB3 or the antibiotic diet had greater ADG compared with those in the control group. No significant differences were observed in BW or ADG among the CB2, CB3, and antibiotic groups. Birds fed the CB2 or CB3 diet had greater concentrations of IgA and IgG in the serum from d 14 to 42 and greater IgM in the serum from d 21 to 42 than those in the control group. Birds fed the CB3 diet had a greater concentration of complement component 3 in the serum than those in the control group from d 7 to 42. Dietary C. butyricum decreased (P < 0.05) Escherichia coli in cecal contents on d 14 and 42, and both CB2 and CB3 decreased (P < 0.05) cecal Salmonella and Clostridium perfringen from d 14 to 42 compared with the control. Broilers fed either CB2 or CB3 had greater cecal Lactobacillus and Bifidobacterium counts from d 21 to 42, and birds fed C. butyricum had greater cecal C. butyricum counts during the whole period compared with those in the control group. The results indicate that C. butyricum promotes growth performance and immune function and benefits the balance of the intestinal microflora in broiler chickens.

Ultrastructural development of the small intestinal mucosa in the embryo and turkey poult: A light and electron microscopy study.

The potential for growth and feed efficiency in turkey poults directly correlates with the early development of the intestinal epithelium. Although the metabolic aspects of enteric maturation have been studied, little is known about the ultrastructural development of the enteric epithelium in the turkey embryo and poult. Hence, the objective of this study was to document the morphological and ultrastructural development of the jejunum mucosa in turkeys, from 15 d of incubation (embryonic day; E) to 12 d posthatch. Intestinal samples from 4 embryos or poults were collected and analyzed by light and electron microscopy (transmission and scanning). In addition, amniotic fluid volume was determined in 6 eggs from E15 to E25. Longitudinal previllus ridges at E15 gradually formed zigzag patterns that led to the formation of 2 parallel lines of mature villi by E25. The volume of amniotic fluid was rapidly depleted as the embryo swallowed it between E19 and E25. During this period, a major increase occurs in villus height, the apical end of epithelial cells is gradually tightened by the junctional complex, and mature goblet cells are visible at the apical end of villi. Villus height steadily increases until reaching a plateau at 8 d. Villi morphology shifts gradually from finger-like projections before hatch to leaf-like projections by 12 d. At this age, the enteric epithelium is in intimate association with microbes such as segmented filamentous bacteria. The profound morphological adaptations of the turkey gut epithelium in response to amniotic fluid swallowing before hatch, and dietary factors and bacteria after hatch, demonstrate the plasticity of the enteric epithelium at this time. Hence, the supplementation of enteric modulators before hatch (in ovo feeding) and after hatch has the potential to shape gut maturation and enhance the growth performance of turkey poults.

Effect of methionine chelated Zn and Mn and corn particle size on Large White male turkey live performance and carcass yields.

Most turkey research has been conducted with a regular corn particle size set through phase-feeding programs. This study's first objective was to determine the effect of increasing corn particle size through the feed phases on performance, processing yield, and feed milling energy usage in Large White commercial male turkey production. Zinc (Zn) and manganese (Mn) are essential microminerals for animals' healthy growth. The source in which these elements are supplied to the bird will determine their bioavailability, effect on bird growth, and subsequent environmental impact. This study's second objective was to measure both inorganic and chelated Zn and Mn sources on turkey performance, turkey carcass processing yields, and subsequent litter residues. Twelve hundred Nicolas Select male poults were randomly assigned to 48 concrete; litter-covered floor pens. The experimental design was a completely randomized block design with a 2 × 2 factorial arrangement of 2 sources of minerals (organic blend vs. inorganic) formulated to match breeder recommendations and 2 types of corn mean particle size (coarse corn [1,000-3,500 µm] vs. fine corn [276 µm]). The ASABE S319.4 standard was used to measure corn mean particle size. Bird performance, carcass processing yield, litter content of Zn and Mn, and pellet mill energy consumption were analyzed in SAS 9.4 in a mixed model. There was a reduction of pellet mill energy usage of 36% when coarse corn was added post-pelleting. Birds fed increasing coarse corn mean particle size were 250 g lighter on average in body weight (BW) than birds fed a constant control mean particle size. No difference was found in feed intake (FI) or feed conversion ratio (FCR). Birds fed methionine chelated Zn and Mn blended with inorganic mineral sources were 250 g heavier on average than birds fed only an inorganic source of minerals. In addition, feeding an organic blend of Zn and Mn resulted in greater breast meat yield. Litter from birds fed the control corn mean particle size, and inorganic minerals had a higher concentration of Zn in the litter but were not different when the chelated Zn/Mn were fed. In conclusion, increasing the corn mean particle size and adding it post pellet could save money during feed milling; however, birds might have a slightly lower BW. A combination of inorganic and chelated Zn and Mn may improve performance and increase total breast meat yields.

Effects of functional oils on the growth, carcass and meat characteristics, and intestinal morphology of commercial turkey toms.

Two experiments were conducted to evaluate the effects of functional oils containing cashew nutshell and castor oil on turkey performance and intestinal morphology. In experiment 1, 585 hatchlings were randomly placed in 15 replicate floor pens, (13 poults/pen) with recycled litter and provided feed and water ad libitum. Birds were randomly assigned to 3 dietary treatments from 1 to 12 wk: nonmedicated control, 0.15% functional oils, and 66-ppm monensin. From wk 13 to 20, each initial treatment group was further divided into 3 treatments-control (no additive), 0.15% of functional oils, or 20 ppm of virginiamycin to produce 9 different treatments, 5 replicate pens per treatment. Data on feed weights were collected weekly, and body weight bi-weekly. At termination (20 wk), birds were euthanized, and their meat was processed to determine mass of carcass sections and meat quality, while intestinal samples were collected for histology. In experiment 1, toms fed monensin or functional oils were 10.5 and 4.5% heavier (P < 0.05), respectively, than the controls at 12 wk. Birds fed monensin had a 4% improvement (P < 0.05) in feed conversion as compared to the other treatments. Neither virginiamycin nor the functional oils affected bird performance when fed from 13 to 20 wk. The jejunum villi surface area at 3 wk was most enhanced (P < 0.05) for the poults fed monensin. Supplementation with functional oils significantly reduced leg yield and thiobarbituric-acid reactive substances of white meat after 7 D of storage (P < 0.05). There were no effects on performance or carcass characteristics in experiment 2. While additional confirmatory studies are needed, functional oils in the diet of turkey toms may be a viable alternative to antibiotic growth promotants.

Effects of diets containing different concentrations of mannanoligosaccharide or antibiotics on growth performance, intestinal development, cecal and litter microbial populations, and carcass parameters of broilers.

The effects of 2 levels of mannanoligosaccharide (MOS) in feed were compared with antibiotic growth promoters on growth performance, intestinal morphology, cecal and litter microbial populations, and carcass parameters in broilers raised in a sanitary environment. Dietary treatments included: 1) antibiotic growth promoter-free diet (control), 2) VIRG (diet 1 + 16.5 mg/kg of virginiamycin), 3) BACT (diet 1 + 55 mg/kg of bacitracin), 4) LMOS (diet 1 + 0.2% MOS), and 5) HMOS (diet 1 + 0.5% MOS). Birds were randomly assigned to 3 replicate pens/treatment (n = 55/pen). Body weight and feed intake were recorded weekly throughout 38 d. At d 14, 24, and 34, a 1-cm segment of duodenum, jejunum, and ileum was used in morphological analysis (n = 9 birds/d per treatment). At the same bird ages, cecal contents were assayed for lactobacilli, bifidobacteria, Salmonella, Campylobacter, and Escherichia coli, whereas litter was analyzed for Salmonella, Campylobacter, and E. coli. Carcass yields (breast fillet and tenders, thigh, drumstick, and wing) were determined at d 38. Body weight, feed conversion, and carcass yields did not differ among treatments. In contrast to birds fed VIRG or BACT, LMOS and HMOS consistently increased (P < 0.05) villi height and goblet cell number per villus in all intestinal segments at d 24 and 34. Bifidobacteria concentrations were higher (P < 0.05) in LMOS- and HMOS-fed birds at all time points. Birds and litter from all treatments were free of Salmonella. At d 14 and 24, cecal E. coli and Campylobacter counts were not different among treatments. In comparison to birds fed control, at d 34, BACT, LMOS, and HMOS significantly reduced (P < 0.05) cecal E. coli concentrations, whereas Campylobacter counts were reduced (P < 0.05) by VIRG, BACT, and LMOS. Litter bacterial counts were not altered by dietary treatments. In conclusion, under conditions of this study, MOS conferred intestinal health benefits to chickens by improving its morphological development and microbial ecology. But, there were no additional benefits of the higher MOS dosage.

Prehatch intestinal maturation of turkey embryos demonstrated through gene expression patterns.

Some of the challenges faced by neonatal turkeys include weakness, reduced feed intake, impaired growth, susceptibility to disease, and mortality. These symptoms may be due to depleted energy reserves after hatch and an immature digestive system unable to replenish energy reserves from consumed feed. To better understand enteric development in turkeys just before hatch, a new method was used to identify the patterns of intestinal gene expression by utilizing a focused microarray. The duodenums of 24 turkey embryos were sampled on embryonic day (E)20, E24, E26, and hatch (E28). The RNA populations of 96 chosen genes were measured at each time point, from which 81 significantly changed (P < 0.01). These genes were clustered by gene expression pattern similarity into 4 groups. The expression pattern of hormone receptors revealed that intestinal tissues may be less responsive to growth hormone, insulin, glucagon, and triiodothyronine during the last 48 h before hatch, when developmental emphasis switches from cell proliferation to functional maturation. Based on gene expression patterns, we concluded that at hatch, poults should have the capacity to 1) digest disaccharides but not oligopeptides, due to increased expression of sucrase-isomaltase but decreased expression of aminopeptidases and 2) absorb monosaccharides and small peptides due to high expression of sodium-glucose cotransporter-4 and peptide transporter-1.

Organic trace minerals and 25-hydroxycholecalciferol affect performance characteristics, leg abnormalities, and biomechanical properties of leg bones of turkeys.

Leg problems and resulting mortality can exceed 1% per week in turkey toms starting at approximately 15 wk of age. Dietary supplementation of organic trace minerals (MIN) and 25-hydroxycholecalciferol (HyD) may improve performance, decrease incidence of leg abnormalities, and increase bone strength. Nicholas 85X700 toms were assigned to 4 treatments consisting of a factorial arrangement of 2 concentrations of MIN (0 and 0.1% of Mintrex P(Se), which adds 40, 40, 20, and 0.3 mg/kg of Zn, Mn, Cu, and Se, respectively) and 2 concentrations of HyD (0 and 92 microg/kg of HyD). Diets were formulated to be equal in nutrient content and fed ad libitum as 8 feed phases. Feed intake and BW were measured at 6, 12, 15, 17, and 20 wk of age. Valgus, varus, and shaky leg defects were determined at 12, 15, 17, and 20 wk of age. Tibia and femur biomechanical properties were evaluated by torsion and bending tests at 17 wk of age. There were no treatment effects on BW. Only MIN significantly improved feed conversion ratio through to 20 wk of age. Cumulative mortality at 3 wk of age was greater among the MIN birds, but it was lower by 20 wk (P = 0.085). The MIN decreased the incidence of varus defects at 17 wk of age; shaky leg at 12, 15, and 17 wk of age; and valgus defects at 15, 17, and 20 wk of age. There were no MIN x HyD interaction effects on individual gait problems. Maximum load and the bending stress required for tibias to break in a 4-point assay were increased with MIN supplementation, especially when HyD was also added. Maximum shear stress at failure of femoral bones in a torsion assay was increased by supplementation with both MIN and HyD together. Dietary supplementation of MIN and HyD may improve biomechanical properties of bones. Dietary MIN supplementation may improve feed conversion of turkeys, likely by decreasing leg problems.

Dietary amino acids under hypoxic conditions exacerbates muscle myopathies including wooden breast and white stripping.

The occurrence of wooden breast (WB) and white striping (WS) of broiler breast myopathies may be associated with least-cost feed formulations and the inclusion of greater amounts of synthetic amino acids. Two experiments were conducted to evaluate the effects of supplemental glutamine (Gln-/+, 0 and 1%) and arginine (Arg-/+, 0 and 0.25%) in a 2 × 2 factorial arrangement. Experiment 1 consisted of 8 replicates using 32 pens and focused on live performance to 44 d of age, carcass yield, and meat quality evaluations at 45 d of age. Live performance parameters including feed intake, BW gain, mortality, and feed conversion were evaluated. Post-harvest carcass yield, breast muscle quality (including WB and WS), proximate analysis, and mineral analysis of breast muscle and tibia bone were also evaluated. Experiment 2 comprised 4 replicates using 8 pens with weekly measurements of blood physiology and muscle myopathy development from 21 to 45 d of age. Broilers fed supplemental Gln and Arg (Gln+/Arg+) produced broilers with greater BW and improved FCR. The WB and WS severity increased with Gln+ diets, while only WB increased using Arg+ diets. Weekly observations revealed the greatest increase in WB myopathies occurred between 28 to 35 d, while WS significantly increased one week later (35 to 42 d). When comparing broilers of similar BW at 45 d, Gln+ diets resulted in greater WS scores and percentage breast muscle fat. Further analysis of WB and WS scores (independent of treatment affect) revealed that increased myopathy scores were associated with increased blood CO2, H2CO3, and reduced O2 with increased meat pH, moisture content, and Ca concentration. These results indicated that increased muscle Ca is associated with increased WB, while increased dietary glutamine and lack of oxygen may have resulted in a reverse flux of the citric acid cycle and reduced electron transport chain activity resulting in increased WS.

Enrichment of the amnion with threonine in chicken embryos affects the small intestine development, ileal gene expression and performance of broilers between 1 and 21 days of age.

The effects of in ovo feeding with threonine (Thr) on intestinal morphology, ileal gene expression and performance of broiler chicken between 1 and 21 d of age (d) were assessed. On day 17.5 of incubation, fertile eggs were randomly allotted to 5 treatments of Thr injection in the amniotic fluid (0; 1.75; 3.5; 5.25; 7%, corresponding to 17.5; 35; 52.5 and 70 mg Thr/mL). After hatch, chicks were given a commercial corn-soybean diet up to 21 d. Daily feed intake (FI), body weight (BW), and food conversion ratio (FCR) were measured from 1 to 7, 14, and 21 d of age. The ileal gene expression of mucin (MUC2), peptide transporter (PepT1), and aminopeptidase enzyme (APN) were evaluated on day of hatch and at 21 d, as well as intestinal morphometric traits. In ovo feeding with threonine significantly increased final weight (FI) and weight gain (WG) and decreased FCR in the period from 1 to 21 d. Threonine levels affected beneficially the villus height, vilo: crypt ratio and villus area on day of hatch and at 21 d. At hatch, all Thr levels increased the expression of MUC2 and PepT1 compared to the control group. APN expression also increased, but for the lowest and the highest threonine levels (1.75 and 7%). At 21 d, there was no effect of threonine on the expression of MUC2, PepT1, and APN. In conclusion, in ovo threonine feeding beneficially affected the morphological and functional development of the intestinal mucosa, which ensured improved performance of chicks at hatch and at 21 d.

Influence of housing system, grain type, and particle size on Salmonella colonization and shedding of broilers fed triticale or corn-soybean meal diets.

Salmonella colonization in poultry may be influenced by grain type and particle size. Broilers reared either in nonlitter cage-based housing or in a conventionally floored litter house from 0 to 42 d were assigned to 1 of 4 dietary treatments: 1) ground corn-soybean meal (C, 560 microm), 2) coarsely ground corn-soybean meal (CC, >1,700 microm), 3) ground triticale-soybean meal (T, 560 microm), or 4) whole triticale-soybean meal (WT). A 4-strain cocktail of Salmonella enterica was orally gavaged into each chick at placement. Growth performance, cecal and fecal Salmonella populations, gizzard and proventriculus pH, intestinal size, jejunum histomorphometry, and carcass yields were measured. Broilers responded differently to the dietary treatments according to the housing system used. At 42 d, birds reared on litter and fed ground grain had greater BW than those fed coarse grain (2.87 vs. 2.71 kg), whereas cage-reared broilers fed ground triticale were heavier than those fed corn (2.75 vs. 2.64 kg). Broilers raised on litter had a better feed conversion ratio than those raised in cages (1.71 vs. 1.81 g/g). Independent of the housing system, relative eviscerated carcass weights of birds fed T and C were heavier than those of CC- and WT-fed broilers (762 vs. 752 g/kg). Generally, the jejunum villus area and mucosal depth were larger, whereas the small intestine was lighter and shorter in broilers raised on litter. Relative gizzard weights of broilers raised on litter and fed the coarser diets were heavier than those of broilers reared in cages and fed finely ground diets. Feeding whole or coarsely ground grains decreased cecal Salmonella populations in 42-d-old broilers (3.8, 3.9, 4.4, and 4.4 log most probable number/g for CC, WT, C, and T, respectively). Additionally, 42-d-old broilers reared on litter had lower cecal Salmonella populations than those in cages (3.8 vs. 4.4 log most probable number/g). In conclusion, as a feed ingredient, triticale is a good alternative to corn, resulting in improved BW and reduced Salmonella colonization. Broilers raised on litter may have achieved lower cecal Salmonella populations than caged birds because access to litter may have modulated the intestinal microflora by increasing competitive exclusion microorganisms, which discouraged Salmonella colonization.

Change in the ileal bacterial population of turkeys fed different diets and after infection with Salmonella as determined with denaturing gradient gel electrophoresis of amplified 16s ribosomal DNA.

Changes in ileal bacterial populations of Salmonella-infected turkeys fed different diets were analyzed by using 16S-V3 PCR denaturing gradient gel electrophoresis. Turkeys raised on litter flooring were fed wheat- and corn-based diets with and without enzyme preparations (XY1 and XY2, respectively) from 0 to 126 d. Preparation XY1 contained exclusively endoxylanase, whereas preparation XY2 contained endoxylanase, protease, and alpha-amylase (Danisco, , Wiltshire, UK). The dietary activity levels of XY1 and XY2 were 2,500 and 650 endo-1,4-beta-xylanase units/kg of feed, respectively. Microbial DNA was extracted from the ileal content of 16-wk-old turkeys, and the 16S rDNA gene was amplified by PCR and analyzed by denaturing gradient gel electrophoresis. Diversity indexes, including richness (number of species, S), evenness (relative distribution of species, EH), diversity (using Shannon's index, H'), and Sorenson's pairwise similarities coefficient (measures the species in common between different habitats, Cs) were calculated. Additionally, diversity indexes were associated with Salmonella prevalence determined from fresh fecal droppings collected from each pen. On the basis of contrast analysis, the wheat-based diets resulted in higher microbial diversity indexes than the corn-based diets (S = 10 vs. 12; EH = 0.9 vs. 0.8; H' = 2.2 vs. 1.9, P < 0.05). Likewise, enzyme supplementation stimulated growth of the microbiota and increased the diversity indexes in comparison with unsupplemented treatments (S = 13 vs. 10; EH = 0.9 vs. 0.8; H' = 2.2 vs. 1.9, P < 0.05). Salmonella prevalence was higher (P < 0.05) at 15 wk in turkeys fed the corn-based diet (Salmonella prevalence = 50%) than in turkeys fed the corn-enzyme (Salmonella prevalence = 13%) and wheat-based (Salmonella prevalence = 0%) dietary treatments. Therefore, contrast analysis showed that birds fed the corn control diet had lower microbiota diversity but higher Salmonella prevalence than birds fed the enzyme-supplemented and wheat-based diets. In contrast, birds fed the wheat-based diets had higher diversity but lower Salmonella prevalence than birds fed the corn-based diets. High dietary nonstarch polysaccharides from wheat and dietary exogenous enzyme supplementation promoted microbial community diversity and apparently discouraged Salmonella colonization through competitive exclusion. Nonstarch polysaccharides and dietary exogenous enzyme supplementation may be practical tools to control enteric pathogens and benefit the intestinal health and food safety of the birds.