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Two dietary sources of zinc (ZnSO4 or organic Zn) were tested in chickens challenged with coccidiosis (Co) or coccidiosis plus Clostridium perfringens (CoCPF). On day 14, the chickens were orally gavaged with ∼5,000 Eimeria maxima sporulated oocysts. On day 19, 20, and 21 chickens challenged with C. perfringens were given a broth culture containing 108 cfu of this bacterium. Productive performance parameters were determined at d 14, 21, and 28. On day 21, necrotic enteritis (NE) lesions were scored, and intestinal permeability was evaluated. Jejunum and cecal tonsils were collected for morphology and gene expression analysis. On day 21, organic Zn improved BW gain by 18.6% (P = 0.07), and FCR by 12% (P = 0.09) in CoCPF challenged chickens vs. birds fed ZnSO4. From 1 to 28, organic Zn increased BW gain (P = 0.02), and improved FCR (P = 0.03) vs. birds fed ZnSO4. At 21 d, NE lesions were only observed in CoCPF birds (P < 0.001), and mortality due to NE was only observed when CoCPF birds were fed ZnSO4 (P = 0.001). Organic Zn fed birds had increased villus height in the jejunum (P = 0.005) and decreased intestinal permeability (P = 0.01) vs. ZnSO4. In the jejunum, organic Zn fed birds showed a downregulation of expression of IL-8 (P = 0.02), and upregulation of IL-10 (P = 0.05) in CoCPF birds vs. ZnSO4- CoCPF birds. As main effect, birds supplemented with organic Zn had higher mRNA expression of TLR-2 (P = 0.02) and IgA (P = 0.01). In the cecal tonsils, organic Zn fed birds showed upregulation of iNOS (P = 0.008) in CoCPF birds vs. ZnSO4-CoCPF birds. Organic Zn supplementation reduced intestinal permeability and attenuated intestinal inflammation of broilers co-challenged with coccidia and C. perfringens. [ABSTRACT FROM AUTHOR]

The objective of the current study was to determine the effect of nitrogen-free diets formulated with 2 ratios of corn starch and dextrose and 2 levels of dietary electrolyte balance (DEB; calculated as Na + K- Cl-, in mEq/kg of diet) on ileal endogenous amino acid (EAA) losses in 48-d-old broiler chickens. On d 43, 240 broiler chickens were allotted to 4 di-etary treatments with 6 replicate cages per diet in a completely randomized design. Each experimental diet was fed for 5 d (d 43-48). All diets were free of nitrogen with 2 ratios of corn starch-to-dextrose (0.31 and 1.04) and 2 levels of DEB (108 and 219 mEq/kg of diet). Final BW and BW loss between birds fed the 2 corn starch-to-dextrose ratios and between birds fed 2 levels of DEB were not different (P > 0.05). Birds fed the diet containing a high level of DEB consumed less (P < 0.05) feed than birds on the low-DEB diet. Birds on the high-corn starch-to-dextrose (1-04) diet showed a tendency for higher (P = 0.08) feed intake. High dietary dextrose level (corn starch-to-dextrose ratio of 0.31) resulted in higher (P < 0.05) ileal DM and energy digestibility. A high level of DEB resulted in higher (P < 0.05) ileal endogenous nitrogen loss. Arginine, lie, Leu, Phe, Val, Ala, Glu, Gly, Pro, and Tyr secretion into the gut increased (P = 0.05) with an increasing-level of DEB. Endogenous His, Lys, Thr, Asp, Cys, and Ser showed a tendency for increased (P = 0.1) losses with a high level of DEB. Mean ileal EAA losses for the indispensable and dispensable amino acids for the low-DEB diet were 81 and 82%, respectively, that of the birds fed the high-DEB diet. The 4 amino acids with the lowest endogenous flow were Met, His, Tyr, and Cys, whereas the highest endogenous flow was found in Glu, Asp, Val, and Leu. Data from the current study showed that EAA losses in the ileum of broiler chickens are significantly affected by DEB, but not by the ratio of corn starch to dextrose. [ABSTRACT FROM AUTHOR]

The selection for growth and carcass traits in poultry meat species has contributed to in-creased interest in understanding and characterizing skeletal growth as the birds struggle to balance skeletal development with increased BW and muscle mass. The objective of this study was to compare the physical characteristics and mineralization of the tibia and fe-mur from commercial Pekin ducks representing circa 1993 and 2010 commercial strains. In 1993, the femur and tibia were collected from 8 ducks at 11 ages between 11 and 53 d. A similar study was done in 2010 in which the femur and tibia were collected from 8 ducks at 12 sample ages between 10 and 49 d. All bones were weighed and the length and width at 50% of length were measured. Each bone was subsequently cut into epiphyseal (top 25% of length) and diaphyseal (midregion at 50% of length) sections. Each bone segment was extracted with ether, hot weighed, and ashed. The 2010 contemporary ducks reached market weight faster than the 1993 ducks. Therefore, statistical comparisons were made at common BW as well as at common ages. The mean tibia length of the 2010 duck was 0.75 cm greater (P < 0.05) at similar ages and similar BW. The percentage ash in the diaphyseal region of the tibia was 3% greater (P < 0.05) in the 2010 versus 1993 ducks. The percentage epiphyseal ash in the femur was 10% lower (P < 0.01) at 10 d and 14 d in the 2010 ducks but there were no significant differences by 18 d of age. The lower epiphyseal ash values at both younger ages and smaller BW in the 2010 contemporary ducks suggests that it is critical to monitor those factors that influence bone mineralization in contemporary ducklings that can achieve market BW at earlier chronological ages. [ABSTRACT FROM AUTHOR]

This experiment evaluated rate of passage (ROP) and apparent ileal amino acid digestibility (AIAAD) of 4 diets varying in ingredient composition fed to broilers from 14 to 22 d of age. Two hundred and 88 Ross X Ross 708 chicks (12 birds per cage; 0.45 m per bird) were randomly assigned to 24 cages (6 replicate cages per treatment) at 1 d of age. Experimental diets were 1) corn-soybean meal-based (CSM) diet containing porcine meat and bone meal (MBM; 5% inclusion), 2) CSM diet containing distillers dried grains with solubles (DDGS; 5% inclusion), 3) semipurified (SP) diet containing MBM (38% inclusion), and 4) SP diet containing DDGS (76% inclusion). Diets were formulated to contain 20% CP and were adequate for vitamins and minerals. Experimental diets were provided from d 14 to 22. On d 18, a total excreta collection was conducted every hour for 12 h from 0800 to 1900 h to determine ROP, and AIAAD was determined on d 22. Time of 1% T1O2 excretion (Tl), 50% TiO2 excretion (T50), and mean retention time (MRT) were used to express ROP. The SP-MBM diet reached Tl (P < 0.05) faster than the SP-DDGS or 2 CSM diets. However, T50 indicated a faster (P < 0.05) ROP for SP-DDGS than the 2 CSM diets, and no significant difference was observed between the 2 SP diets. The MRT of the SP-DDGS diet (5.13 h) was less (P < 0.05) than the MRT of the SP-MBM, CSM-MBM, and CSM-DDGS diets, which resulted in values of 5.48, 5.62, and 5.58 h, respectively. In general, the AIAAD values were higher (P < 0.05) for the 2 CSM diets than for SP diets. Except for His, no statistical differences were observed between the AIAAD of the 2 CSM diets. Comparing the 2 SP diets, AIAAD was usually similar or higher [P < 0.05) for SP-DDGS, except for His, Lys, and Gly, which were higher (P < 0.05) for SP-MBM. Based on T50 and MRT, SP diets containing DDGS had a faster ROP in broilers than CSM diets or SP diets containing MBM. [ABSTRACT FROM AUTHOR]

ABSTRACT The negative effects of aflatoxins (AFLA) on hepatic necrosis and total tract digestibility of energy, N, and amino acids have been well documented. However, the question remains if this is an effect on nutrient metabolizability alone or an effect on the intestine, or both, resulting in increased endogenous nutrient loss or reduced nutrient retention, or both. There- fore, a 2-wk feeding study with a crude AFLA culture was conducted with laying hens to measure endogenous losses and digestive functionality of the intestine. HyLine W36 hens were fed 1 of 4 experimental diets containing a crude AFLA culture from 20 to 22 wk of age. Diets were analyzed to contain 0, 0.6, 1.2, or 2.5 mg/kg of AFLA B1. Dietary AFLA concentration had no effect on BW, egg production, or feed intake. Intestinal crypt depth (but not villus length) increased linearly with in- creasing AFLA concentration. Similarly, specific activity of the intestinal disaccharidase, maltase, increased quadratically by feeding up to 1.2 mg/kg of AFLA and declined at 2.5 mg/kg of AFLA (P ⩽ 0.022). Although there was no effect of AFLA on goblet cell number, density, or crude mucin excretion (P> 0.05), sialic acid excretion increased quadradically such that it was increased 12% when 0.6 and 1.2 mg/kg of AFLA was fed versus the control (P ⩽ 0.025). Digestibility of DM and N per hen per day were unaffected by AFLA. Feeding of 0.6 and 1.2 mg/kg reduced the apparent digestible and AMES of the hen by 10 and 4%, respectively (P ⩽ 0.025). Because intestinal characteristics (intestinal morphology, sialic acid production, and apparent digestible energy) were altered by AFLA feeding, it can be surmised that AFLA can have a direct or indirect effect, or both, on functionality of the gastrointestinal tract. [ABSTRACT FROM AUTHOR]

Two experiments were conducted with a co-product of corn endosperm fermentation. The first experiment determined nutrient digestibility of high- protein corn distillers dried grains (HP-DDG; 54% CP) after feeding semi-purified diets from 15 to 22 d of age. The AME1, of HP-DDG was 2,526 kcal/kg, whereas standardized ileal Lys, Met, and Thr digestibilities were 73.0, 84.9, and 73.0%, respectively. In a second experiment, an industry control diet (I) regimen was compared with that of either an approximate 25 or 50% replacement for the level of 48% CP soybean meal (SBM) inclusion in the diet utilizing the amino acid digestibility and AMEII determined from the first experiment. From 0 to 14, 14 to 28, and 28 to 42 d of age, the HP-DDG in the 50% SBM replacement diet was added at 25, 23.5, and 21% of the diet, respectively. To meet digestible amino acid needs, the diet containing 50% SBM replacement with HP-DDG contained 3.2, 3.6, and 4.4% units more CP than the I diet regimen from 1 to 14, 14 to 28, and 28 to 42 d of age, respectively. Dietary replacement of up to 50% of SBM inclusion with HP-DDG had no effect on bird performance at 14 or 42 d of age or breast fillet yield at 42 d of age; however, it decreased BW gain and increased feed:gain ratio from 14 to 28 d of age. Birds consuming a diet with 50% replacement of SBM with HP-DDG consumed 17.1% more N compared with those consuming I diets. This additional N and fiber consumed resulted in birds being fed the 50% replacement for SBM diet excreting 21.9 and 31.8% more manure DM and N, respectively. Due in large part to the amino acid profile and digestibility of HP-DDG, use of this feedstuff as a large proportion of the diet is feasible but results in more manure and manure N from broilers. [ABSTRACT FROM AUTHOR]

An experiment was conducted to study the effects of high dietary Cu and Cu source on the pH of digesta from the gizzard, duodenum + jejunum, ileum, and complex size of Ca, Zn, and Cu in the duodenum + jejunum digesta of broiler chickens. Ross 308 male broiler chicks were randomly assigned to 32 cages and fed 1 of 4 treatments: control, 250 ppm Cu from sulfate, 250 ppm Cu from lysinate, and 250 ppm tribasic Cu from chloride from 15 to 21 d of age. Copper supplementation and Cu source had no effects on pH of gizzard or duodenum + jejunum contents. Copper supplementation, however, increased the pH of the ileal contents (P < 0.05) but was not affected by Cu source. Neither Cu supplementation nor Cu source had significant effects on the solubility of Ca in the duodenum + jejunum contents, and the portions of Ca existing in different soluble complex sizes: >100,000, 100,000 to 30,000, 30,000 to 5,000, and <5,000 molecular weight (MW) in the duodenum + jejunum digesta. About 80% of soluble Ca, Cu, and Zn was associated with either large complexes (>100,000 MW) or small complexes (<5,000 MW). The solubility of supplemental Cu in digesta was from 59 to 61% (P < 0.05), but solubility was not affected by Cu source. No effects on portions of Cu existing in different sizes of complexes in the supernatant were noted. Copper lysinate decreased the Zn solubility in the digesta (P < 0.05), but Cu sulfate and tribasic Cu chloride supplementation did not. Copper supplementation increased (P < 0.05) the percentage of Zn associated with large complexes (>100,000 MW) and decreased (P < 0.05) the percentage of Zn associated with small complexes (<5,000 MW; P <0.05), thereby suggesting an antagonism between Cu and Zn. [ABSTRACT FROM AUTHOR]

In an effort to reduce carcass contamination and consequent reprocessing, market-age broilers are often subjected to feed withdrawal (FW) before processing to reduce intestinal content and intestinal ruptures during processing. However, little is known regarding the effects of FW on mucus content and intestinal morphology. Therefore, 2 experiments were conducted to determine the effects of FW on intestinal characteristics. Male broilers were raised in floor pens on standard industry diets to 42 and 39 d of age for Experiments (Exp.) 1 and 2, respectively. In Exp. 1, feed was removed 24, 12, 8, and 0 h before sampling, respectively (n = 5 birds/time). Birds remained on litter with access to water for the first 4 h of the FW period and were then placed in crates. Body weights, left pectoralis major weights, and distal ileal and jejunal segments were collected for determination of morphological characteristics. For Exp. 2, birds (n = 8 birds/time) were subjected to 0, 12, and 24 h of FW. Birds were injected with 5-bromo-2′-deoxyuridine and thymidine at 24 and 21 h, respectively, before sampling to determine epithelial cell migration rates. One-centimeter distal ileal segments were collected for mucus quantification at 0, 12, and 24 h. In Exp. 1, ileal villi heights were unaffected by FW, but villus width and crypt depth decreased with increasing FW time (P ≤ 0.05). Jejunal villus height increased as FW progressed. Jejunal crypt depths increased until 12 h of FW and then declined at 24 h. Mucus content decreased linearly and was reduced by 46% from 0 to 24 h FW (P < 0.05). The intestinal morphology alterations and the depletion of intestinal mucus that occur during a short-term FW may reduce the integrity of the intestine. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to determine the nutritional value and impact of dehulled degermed corn (DDC) in diets of broiler chickens. In the first experiment, 4 experimental diets were fed from 14 to 21 d of age with increasing quantifies of DDC replacing corn as the sole source of energy and protein (93.4% of diet). The AMEn was determined to be 3,267 and 3,364 kcal/kg for the corn grain and DDC, respectively. Apparent ileal amino acid digestibility was determined with birds at 21 d of age. Digestibility of threonine, lysine, arginine, and tryptophan was significantly less in birds fed the DDC versus a corn diet (P < 0.05). In the subsequent experiment, birds were fed diets from hatch to 42 d of age with corn or DDC as the primary grain source. By 42 d of age, BW and feed consumption between birds fed the corn or DDC diet were similar (P > 0.05). However, birds fed the DDC diet excreted 78.1 g less DM and 1.54 g less P by 42 d of age (P < 0.05). In conclusion, replacement of corn with DDC resulted in similar performance of broilers to 42 d of age with reduced excretion of DM and P. [ABSTRACT FROM AUTHOR]

Turkey poults and Pekin ducklings hatch from eggs of similar weights and have the same incubation periods and body weights at hatch. The male Pekin duckling, however, can attain a market weight of 3.2 kg in approximately 6 wk, whereas at the same age, male turkeys only weigh approximately 2.1 kg. For this study, fertile turkey eggs (n 400, mean weight: 87.2 g, range: 85 to 89.9 g) and Pekin duck eggs (n = 565, mean weight: 88.6 g, range: 85 to 92.0 g) were weighed and incubated. Embryos and hatchlings were sampled during the last week of incubation, at hatch, and through 7 d of age. Yolk-free BW of poults were 2.7 g heavier than ducklings at hatch. Yolk-free BW of ducklings, however, were greater than poults at 1 d of age (P ≤ 0.06), and by 7 d of age ducklings were 140 g heavier (P ≤ 0.01). Yolk sac weight was similar at 21 and 25 d of incubation, yet was significantly lower in ducks at hatch, 1, and 2 d of age (P ≤ 0.05). In the duckling, jejunum and ileum weights (3.7x heavier), length (1.6× longer), and density (g/cm; 2.3x more dense) were consistently heavier than in the turkey from hatch through 7 d (P ≤ 0.01). Histological sections of the distal jejunum revealed more rapid villus growth in the duck from 0 to 3 d of age. The combination of increased intestinal growth (weight and length) and maturation (villus length) allowed ducks to achieve an additional 143 g of BW gain during the critical hatch through 7 d of growth. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the effect of whole corn inclusion before pelleting on performance, processing yield, and microbiome modulation of broilers from 1 to 42 d of age. One thousand male Ross 708 broilers were randomly distributed among 4 treatments, with 10 replicate pens per treatment and 25 broilers per pen. Treatments consisted of 4 levels of whole corn (0, 2.5, 5.0, and 7.5%) replacing ground corn. Feed intake and BW were determined at 14, 28, and 42 d, and feed conversion ratio (FCR) was calculated by considering the weight of the mortality. At 42 d, ileal and cecal contents were analyzed to determine intestinal microbiota. At 43 d, 10 birds per pen were processed for yield determination. Data were evaluated using the ANOVA procedure (PROC GLM), and means were separated using Tukey's honestly significant difference procedure. Inclusion of whole corn did not influence BW and feed intake (P < 0.05) until 42 d of age. However, broilers consuming diets with 2.5, 5.0, and 7.5% whole corn had lower FCR from 28 to 42 d of age (1.93, 1.95, and 1.94 vs. 2.00, P, 0.05) than in broilers fed with diets containing 0% whole corn. Broilers fed with diets containing 5% whole corn had higher breast meat yield (29.11 vs. 28.40%, P, 0.05) than broilers fed with 7.5% whole corn, but yields were similar to broilers fed with diets without whole corn. Diets with 7.5% whole corn showed a trend toward increased Faecalibacterium (P = 0.07) and decreased Lactobacillus (P = 0.08) in cecal microbiota compared with diets with 5% whole corn. The results of this experiment indicated that up to 5% whole corn can replace ground corn in broiler diets from 1 to 42 d. [ABSTRACT FROM AUTHOR]

This study was conducted to determine whether protein solubility (PS) of rapeseed meals (RSM) can affect standardized ileal amino acid digestibility (SIDAA) in meat ducks. A total of 1,168, 14-days-old ducks were randomly allotted to 23 treatments (6 cages per diet, 8 ducks per cage) and 1 nitrogen-free diet treatment (8 cages, 8 ducks per cage) based on body weight. The 23 experimental diets consisted of a corn–soybean meal basal diet, and 22 diets containing 15% RSM: 85% basal diet. Titanium dioxide (0.5%) was included in all diets as an indigestible marker. On day 18, all ducks were euthanized by carbon dioxide asphyxiation and digesta samples from the ileum. The contents of PS, ether extract (EE), glucosinolate, isothiocyanate, and oxazolidine were significantly different (P < 0.05) in the 22 RSM, with the CV being 52.62, 49.23, 86.84, 90.19, and 81.98%, respectively. The content of lysine (Lys) and methionine in the 22 RSM samples ranged from 1.03 to 2.71% (CV 24.19%) and from 0.33 to 0.65% (CV 15.17%), respectively. The SIDAA, except for leucine (Leu) and tyrosine, of the 22 RSM samples varied significantly (P < 0.05). A positive correlation was observed (P < 0.05) between PS and standardized ileal digestibility (SID) of Lys, isoleucine, valine, phenylalanine, histidine, serine, cysteine, and tyrosine. The R² value of multiple linear regression equations for predicting the SID of amino acids (AA) was best for Lys (R2 = 0.958 using dry matter, crude protein, EE, crude fiber, acid detergent fiber, and PS) and least significant for Leu (R² = 0.348 using crude fiber and ash) with intermediate values for other AA (R² = 0.359–0.837, P < 0.05). These results suggest that PS varying from 15.06 to 98.08%, also varied considerably in the proximate nutrient content, AA composition, and antinutritional factor content, which was reflected in considerable differences in the duck's SID of AA in RSM. Therefore, PS value can partly reflect the quality of RSM. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to study the effects of dietary zinc (Zn) source on gene expression of Zn transporters (metallothionein [MT], ZIP 3, 5, 8, 9, 10, 11, 13, and 14, and ZnT 1, 4, 5, 6, 7, 9, and 10) in the jejunum and cecal tonsils of broilers challenged with coccidia or coccidia plus Clostridium perfringens. A 2 × 2 factorial design was used with 2 Zn sources (90 mg Zn/kg from either ZnSO4 or an organic Zn, Bioplex® Zn) and challenged with approximately 5,000 oocysts of Eimeria maxima at 14 d of age with or without C. perfringens (108 CFU/bird) at 18, 19, and 20 d of age (8 pens per treatment and 8 birds per pen) after which 1 bird/pen was sampled at 21 d of age. In the jejunum, co-infection resulted in higher ZnT 5 and 6 gene expression, while organic Zn fed birds had lower ZIP 5 and 11, and higher ZnT1. Additionally, an interaction of challenge by Zn source was noted wherein ZnT10 was unaffected by the C. perfringens in the organic Zn treatment but was 2.7-fold lower in the co-infected ZnSO4 fed birds. S100A9 gene expression, a biomarker of inflammatory response in necrotic enteritis, increased 2 and 2.8-fold in the cecal tonsils and jejunum with the co-infection, respectively. Supplementation with organic Zn lowered S100A9 by 1.9 and 4.4-fold in the cecal tonsils and jejunum, respectively, when birds were supplemented with ZnSO4. Notably, MT, ZIP 3, 8, 9, 10, 13, or 14, and ZnT 4, 7, and 9 were unaffected by Zn source and/or method of challenge. An interaction of challenge by Zn source was also noted for serum Zn concentration, which was reduced when birds were challenged with C. perfringens and fed ZnSO4 but no difference between challenge method when birds were fed organic Zn. Based on the expression of ZnT and ZIP genes, more Zn trafficking due to treatment occured in the jejunum than cecal tonsils, but further studies are needed to ascertain how Zn source regulates intracellular free Zn concentrations and whole-body Zn status during an enteric challenge. [ABSTRACT FROM AUTHOR]

An abstract of the article "Developmental Changes in Enterocyte Morphology in the Small Intestine of Avian Embryos," by M. E. Freeman and colleagues is presented.

An abstract of the article "Replacement of soybean meal with high-protein corn distillers grain in broiler diets," by and colleagues is presented.

In 2003, the US Environmental Protection Agency (EPA) released new guidelines for Concentrated Animal Feeding Operations (CAFO). Under the new guidelines, permitted CAFOs will be required to develop a Nutrient Management Plan (NMP). In most cases, with minor additions, a USDA, Natural Resources Conservation Service (NRCS) Comprehensive Nutrient Management Plan (CNMP) will satisfy the requirements of an NMP. One of the Core Elements of the CNMP is feed management. In 2005, a national feed management education project was funded by the NRCS Conservation Innovation Grant program (CIG). The project will develop, test, and implement a National Feed Management Education Program and Assessment Tools into a Comprehensive Nutrient Management Plan. The goal of the project is to increase the understanding of feed management to agricultural professionals, with an emphasis on environmental and financial sustainability of livestock and poultry operations. A team consisting of consulting animal nutritionists, technical service providers (TSPs), Extension Specialists, and research scientists will accomplish the following program objectives: 1) develop and evaluate a two-tier tool for assessing the impacts of feed management practices on whole farm nutrient balance for animal nutritionists, NRCS staff and TSP advisors, 2) develop the content of a Feed Management chapter for the NRCS Agricultural Waste Management Field Handbook (AWMFH), and 3) develop and implement an education program targeting integration of feed management into a CNMP. Specific outcomes are: 1) develop educational materials that are applicable at the national level, 2) provide training for NRCS staff, agricultural professionals, and TSPs in feed management concepts and practices that minimize import of nutrients to the farm, 3) provide training in the use of computer models and software for strategic ration balancing, whole farm nutrient balance, and nutrient excretion estimates based upon feed and animal performance inputs, and 4) develop a chapter for the NRCS AWMFH on Feed Management. [ABSTRACT FROM AUTHOR]

The effect of coccidial vaccine challenge (CVC, Coccivac®B; challenged, CHA; or unchallenged, NCH) on ileal endogenous amino acid (IEAA) losses and standardized ileal AA digestibility (SIAAD) in 21- and 42-day-old broilers fed a corn-soybean meal-dried distillers’ grains with solubles-poultry by-product meal-based diet (Expt. 1) and the effect of supplemental AA in ameliorating the effect of CVC (Expt. 2) were evaluated. Expt. 1 was designed as a 2 (d 21 or 42) x 2 (NCH or CHA) factorial arrangement of treatments with 8 replicates in a complete randomized design. The CVC birds were gavaged with 12 x coccidial vaccine on d 15 and 36 and were sampled on 6 d post challenge. SIAAD was determined by correcting apparent ileal AA digestibility for IEAA losses. Feed intake (FI) and BW gain were higher (P ≤ 0.05) in 21-day-old NCH birds compared to the 21-day-old CHA birds while 42-day-old birds had higher FI and BW gain than 21-day-old NCH and CHA birds. Ileal endogenous nitrogen loss was higher (P ≤ 0.05) in 42-day-old CHA birds compared to 42-day-old NCH birds. Apparent ileal AA digestibility in 21-day-old CHA birds was lower (P ≤ 0.05) than for 21-day-old NCH and 42-day-old NCH and CHA birds. SIAAD in 21-day-old CHA birds was lower (indispensable AA = 15.2 and dispensable AA = 17.8%-unit; P ≤ 0.05) than for 21-day-old NCH and 42-day-old NCH and CHA birds. Apparent ileal digestibility and total tract utilization of DM, N, and energy were not different between d 21 NCH and d 42 NCH and CHA birds but higher (P ≤ 0.05) than for d 21 CHA birds. Supplemental AA restored feed efficiency, but not BW gain, to that of the positive control (0.715 vs. 0.737). Results from Expt.1 showed that CVC significantly influenced ileal AA digestibility in 21- but not in 42-day-old birds. Expt. 2 showed that consideration of SIAAD in feed formulation may benefit feed efficiency. [ABSTRACT FROM AUTHOR]

A 20-day trial was conducted to determine the impact of aflatoxin B1 (AFB1) and dietary protein concentration on performance, nutrient digestibility, and gut health in broiler chicks. The 6 dietary treatments were arranged in a 2 x 3 factorial with 3 crude protein (CP) concentrations (16, 22, and 26%) with or without 1.5 mg/kg AFB1. Each diet was fed to 6 replicate cages (6 chicks per cage) from zero to 20 d of age. Endogenous N and amino acid loss were estimated from birds fed a N-free diet with or without 1.5 mg/kg AFB1. A significant interaction between AFB1 and CP concentration was observed for growth performance, where reduction of BW gain, feed intake, gain:feed ratio, and breast muscle weight by AFB1 were most profound in birds fed the 16%-CP diet, and were completely eliminated when birds were fed the 26%-CP diet (AFB1 by CP interaction; P ≤ 0.023). Similarly, AFB1 reduced serum albumin, total protein, and globulin concentrations in birds fed 16 and 22% CP diets, but not in those fed the 26%-CP (AFB1 by CP interaction; P ≤ 0.071). Gut permeability was increased in birds fed AFB1-contamiated diets as measured by serum lactulose/rhamnose ratio (main effect; P = 0.04). Additionally, AFB1 tended to increase endogenous N loss (P = 0.09), and significantly reduced apparent ileal digestible energy and standardized ileal N and amino acid digestibility in birds fed the 16%-CP diet, while birds fed higher dietary CP were not affected (AFB1 by CP interaction; P ≤ 0.01). Further, AFB1 increased the translation initiation factor 4E-binding protein (4EBP1), claudin1, and multiple jejunal amino acid transporters expression (main effect; P ≤ 0.04). Results from this study indicate that a 1.5 mg AFB1/kg diet significantly impairs growth, major serum biochemistry measures, gut barrier, endogenous loss, and energy and amino acid digestibility. Aflatoxicosis can be augmented by low dietary CP, while higher dietary CP completely eliminated the impairment of performance, serum proteins, and nutrient digestibility from aflatoxicosis in zero to 20 d broiler chicks. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the efficiency of a hydrated sodium calcium alu-minosilicate (HSCAS) adsorbent to ameliorate the adverse effects of 0.5 to 2 mg of aflatoxin B1 (AFB1)/kg in broiler chicks. The study consisted of 8 dietary treatments, including 4 concentrations of AFB1 (0, 0.5, 1, and 2 mg/kg) with or without HSCAS (0.5%) fed to 8 replicate cages per diet (6 males chicks per cage) from 0 to 21 d of age. Cumulative feed intake, BW gain (P < 0.0001), and G:F [P = 0.004) of birds fed the 2 mg of AFB1/kg of diet were significantly lower in comparison with birds fed 0 to 1 mg of AFB1/kg. Relative liver weight was increased in the 2 mg of AFB1/kg group (P < 0.0001). Dietary HSCAS improved cumulative BW gain (main effect P = 0.06), particularly from 14 to 21 d of age (P = 0.037). Dietary HSCAS also reversed the increase in relative liver weight for birds fed AFB1 (P = 0.019). Dietary AFB1 negatively affected major serum parameters (albumin, total protein, globulin, phosphorus, glucose, alkaline phosphatase, and creatine Phosphokinase), whereas supplementation with HSCAS partially alleviated the affected serum biochemistry. In addition, serum complement activity and liver gene expression were negatively affected by 2 mg of AFB1/kg. The HSCAS supplement increased the liver expression of catalase and superoxide dismutase (P < 0.05). Results from this study indicate that dietary supplementation with HSCAS can effectively improve BW gain and partially ameliorate aflatoxicosis for broiler chicks fed AFB1-contaminated feeds. [ABSTRACT FROM AUTHOR]

In this study, 2 experiments determined the effects of increasing dietary concentrations of deoxynivalenol (DON) on performance, intestinal morphology, and measures of innate immunity in broilers and turkeys. For experiment 1, the 3-wk study used 5 concentrations of DON (up to 18 or 10 mg of DON/kg of feed in broilers or turkeys, respectively) from naturally contaminated corn. The BW gains were cubically or quadratically affected by the increasing dietary concentrations of DON for broilers and turkeys, respectively; however, feed consumption was not affected. For experiment 2, the birds were subsequently injected or not injected with lipopolysaccharide (LPS) 24 h before tissue and blood sample collection. Dietary DON had no effect on intestinal crypt depth, but linearly increased the mid-ileal villus height in broilers (P = 0.04). An interaction was observed between the LPS challenge and the dietary DON with regards to heterophil to lymphocyte ratio (P < 0.05) in broilers, but not in turkeys. The cecal tonsil cell phagocytosis of microbeads was not affected by the dietary concentration of DON either with or without the subsequent LPS challenge for both broilers and turkeys. Conversely, the phagocytic capacity of cecal tonsil cells to engulf killed Staphylococcus aureus was significantly reduced (over 2.5-fold) when broilers were fed the highest concentration of dietary DON (non-LPS-challenged; P < 0.05). However, diets containing DON showed no effects on broilers when they were challenged with LPS. Antibody-dependent phagocytosis (S. aureus) was not affected in turkeys fed DON. Overall, corn naturally contaminated with up to 18 or 10 mg/kg of DON (broiler or turkey, respectively) reduced bird BW gain at 21 d of age, reduced antibodydependent phagocytosis of previously killed S. aureus by cecal tonsil cells in non-LPS-challenged broilers, and greatly decreased heterophil to lymphocyte ratios in LPS-challenged broilers. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate and compare amino acid digestibility of several feedstuffs using 2 commonly accepted methods: the precision-fed cecectomized rooster assay (PFR) and the standardized ileal amino acid assay (SIAAD). Six corn, 6 corn distillers dried grains with or without solubles (DDGS/DDG), one wet distillers grains, one condensed solubles, 2 meat and bone meal (MBM) and a poultry byproduct meal were evaluated. Due to insufficient amounts, the wet distillers grains and condensed solubles were only evaluated in roosters. Standardized amino acid digestibility varied among the feed ingredients and among samples of the same ingredient for both methods. For corn, there were generally no differences in amino acid digestibility between the 2 methods. When differences did occur, there was no consistent pattern among the individual amino acids and methods. Standardized amino acid digestibility was not different between the 2 methods for 4 of the DDG samples; however, the PFR yielded higher digestibility values for a high protein DDG and a conventionally processed DDGS. The PFR yielded higher amino acid digestibility values than the SIAAD for several amino acids in 1 MBM and the poultry byproduct meal, but it yielded lower digestibility values for the other MBM. Overall, there were no consistent differences between methods for amino acid digestibility values. In conclusion, the PFR and SIAAD methods are acceptable for determining amino acid digestibility. However, these procedures do not always yield similar results for all feedstuffs evaluated. Thus, further studies are needed to understand the underlying causes in this variability. [ABSTRACT FROM AUTHOR]

Mucin dynamics may be particularly sensitive to a Thr deficiency due to the high concentration and structural importance of Thr in the mucin protein backbone. Intestinal mucin secretion, expression of mucin gene (MUC2), and histological characteristics were investigated in male broilers and White Pekin ducklings offered diets containing 3.3, 5.8, or 8.2 g of Thr/kg in 4 studies. Seventy-two birds of each species were fed a standard broiler starter diet from 1 to 14 d of age followed by assignment to 3 dietary treatments in a randomized complete block design for a 7-d feeding trial in experiment 1 (broilers) and experiment 2 (ducklings). The dietary treatments consisted of an isonitrogenous corn-soybean meal-based diet with the addition of crystalline amino acids and graded levels of Thr. Dietary treatments contained 3.3, 5.8, or 8.2 g of Thr/kg. Dietary formulation and experimental design for experiments 3 (broilers) and 4 (ducklings) were similar to experiments 1 and 2 except that birds were fed 3.3 or 8.2 g of Thr/kg for durations of 7 or 14 d. For chicks, increased dietary Thr resulted in higher levels of intestinal crude mucin excretion in experiment 1 (P = 0.04) but not in experiment 3, whereas intestinal sialic acid excretion increased in experiment 3 (P = 0.02) but not in experiment 1. Furthermore, there was no effect of Thr on intestinal goblet cell density or MUC2 mRNA abundance for broilers. For ducklings, there was an increase in intestinal crude mucin excretion in both experiments (P < 0.05) as dietary Thr increased, although there was no effect of Thr on intestinal sialic acid excretion. There was a tendency for an increase in intestinal goblet cell density (cells/μm of villus length; P = 0.09) as dietary Thr increased in experiment 2. For experiment 4, intestinal MUC2 mRNA abundance increased (P = 0.03) as dietary Thr increased for the 14-d feeding trial but not for the 7-d feeding trial. The data establish a link between dietary Thr and intestinal crude mucin dynamics in chicks for experiment 1 and ducklings for both experiments. [ABSTRACT FROM AUTHOR]

Copper is normally supplemented in poultry diets as a growth promotant and antimicrobial. However, there are conflicting reports about the growth benefits and little information about how Cu affects the microbiota in the intestinal tract of poultry. Therefore, in vitro and in vivo experiments were conducted with broilers to determine the effects of Cu source and supplementation on ileal microbiota. The influence of Cu on growth of lactobacilli and Escherichia coli in media inoculated with ileal contents was determined in the first study. When Cu sulfate pentahydrate was supplemented to the cultures, quadratic increases in lactobacilli to graded concentrations of Cu up to 125 mg/kg and quadratic decreases in E. coli up to 250 mg/kg of Cu were observed after 24 h of incubation at 37°C. However, when tribasic Cu chloride (TBCC) was supplemented, neither linear nor quadratic responses to graded concentrations of dietary Cu were observed on number of lactobacilli or number of E. coli. The effects of Cu and Cu source on ileal microbiota and growth performance in broiler chickens were determined in the second study. Bird performance was not affected by Cu source or concentration. The bacterial culture enumeration results revealed that supplementation with 187.5 mg/kg of Cu from Cu sulfate pentahydrate and TBCC had no effect on number of ileal lactobacilli of birds. The denaturing gradient gel electrophoresis analyses of ileal microbial communities revealed that neither Cu supplementation nor source had effects on the number of bacterial species predominant in the ileal digesta or associated with the ileal mucosa. Supplementation with TBCC supplementation significantly increased the similarity coefficients of microbiota in the ileal mucosa compared with cross-products of all individuals. This suggests that TBCC may alter the intestinal microbiota, yet this shift had no effect on bird performance. [ABSTRACT FROM AUTHOR]

To determine the effects of delayed access to feed on intestinal villus development, bacterial translocation, and salmonella attachment potential in turkey poults, poults were given ad libitum access to water and feed immediately after hatch (FED) or were delayed access to water and feed for 48 h (DLY). In experiment 1, FED poults were heavier until 5 d postfeeding at which time villi were 50 μm longer and 6.8 μm wider, crypts were 5.9 μm deeper, and there were more goblet cells per villus than in the DLY poults. The DLY poults also had reduced numbers of proliferating enterocytes in the villus and higher apoptotic labeling at 1, 2, and 5 d postfeeding. In experiment 2, DLY poults had higher numbers of aerobic bacteria in the ileal digesta and ileal tissue when compared with the FED poults at 1 d postfeeding. To study salmonella attachment potential to the ileum, a segment of the ileum was inoculated with a salmonella culture, incubated for 1 h at 37°C, and flushed; the tissue was homogenized, and numbers of remaining salmonella were enumerated. No differences in salmonella attachment potential were noted between FED and DLY poults. In conclusion, early access to ad libitum feed in poults stimulated growth and development of small intestinal villi and their absorptive surfaces, whereas delayed access to feed resulted in delayed enterocyte proliferation and greater enterocyte apoptosis during the first week posthatch as well as greater numbers of aerobic bacteria associated with the small intestine shortly after hatch. [ABSTRACT FROM AUTHOR]

Studies were conducted to determine the efficacy of synbiotic applications to combat the negative effects of necrotic enteritis (NE). An in vitro study was conducted to test the effect of probiotics species supernatants to decrease Clostridium perfringens (CP) proliferation. Lactobacillus reuteri, Enterococcus faecium, Bifidobacterium animalis, and Pediococcus acidilactici culture supernatants decreased the proliferation of CP at 1:1 supernatant-to-pathogen dilution in vitro. Two in vivo studies were conducted to determine the in vivo response of synbiotic supplementation containing the aforementioned probiotic strains on broiler production performance and caecal CP load in broilers induced with NE infection. In experiment 1, 75 broiler chicks were randomly allotted to 3 treatment groups, control (basal diet), ionophore (Salinomycin), and synbiotic (PoultryStar me), from day of hatch, and NE was induced in all birds. There were no significant treatment effects on BW, feed consumption, and feed gain ratio. However, at 35 D, ionophore or synbiotic supplementation increased (P, 0.05) villi height and decreased interleukin (IL)-1 mRNA abundance, while synbiotic supplementation increased (P, 0.05) IL-10 mRNA abundance compared with the control group, respectively. In experiment 2, 360 broiler chicks were randomly allotted to 3 treatments, an unchallenged negative control (control; basal diet), challenged positive control (NE; basal diet), or NE 1 synbiotic group (synbiotic). At both 21 and 42 D of age, NE birds had decreased (P, 0.05) BW, feed conversion, and jejunal villi height compared with control, while NE 1 synbiotic birds were not different from control groups. At 42 D of age, NE birds had 2.2 log/g increased CP in the ceca contents compared with control, while synbiotic birds had CP load that was not different than that of the control group. NE 1 synbiotic birds had significantly greater amounts of bile anti-CP IgA than the control and NE groups. It can be concluded that synbiotic supplementation decreased CP proliferation in vitro and caecal CP load in vivo while improving production parameters during an NE infection in broilers. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of the mycotoxins deoxynivalenol (DON), fumonisins (FUM), and their combination on growth performance, nutrient, and energy digestibility in broilers. A total of 960 Cobb-Cobb male broilers were obtained on the day of hatch and placed 10 birds per cage with 8 cages per treatment. The experiment consisted of 12 treatments: control; DON 1.5 mg/kg; DON 5.0 mg/kg; FUM 20.0 mg/kg; DON 1.5 mg/kg + FUM 20.0 mg/kg; and DON 5.0 mg/kg + FUM 20 mg/kg. The remaining dietary treatments were the correlative nitrogen-free diets (NFD) for determining the endogenous nutrients loss. All birds were fed with a corn−soybean meal diet from days 1 to 15, until birds from latter 6 treatments were switched to their correlative NFD diet from days 15 to 21. Feed and BW were weighed by cage on days 8, 15, and 21. On day 21, ileal digesta was collected for digestibility determination. Both DON 1.5 mg/kg + FUM 20 mg/kg and DON 5.0 mg/kg + FUM 20 mg/kg treatments showed reduced feed intake (P ≤ 0.05) from days 8 to 15 and days 15 to 21. However, no significant effects were noted for BW gain or mortality-adjusted feed conversion ratio after adding single or combined mycotoxin on days 8 and 15. At day 21, cumulative BW gain was less (P ≤ 0.05) in birds fed with the mycotoxin combination diets than the control. No significant changes were shown for ileal endogenous amino acids losses. Control treatment had significantly higher (P ≤ 0.05) apparent ileal energy digestibility than the DON 5.0 mg/kg + FUM 20.0 mg/kg treatment (3,126 vs. 2,895 kcal/kg), representing a 5%-unit loss in apparent DM digestibility. No significant difference was found for standardized crude protein and amino acid digestibility. In conclusion, the combination of DON and FUM (DON 1.5 mg/kg + FUM 20 mg/kg or DON 5.0 mg/kg + FUM 20 mg/kg) reduced DM and ileal energy digestibility, which negatively affected BW gain in broilers. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare the effects of inorganic and proteinate Zn in chickens challenged with coccidia and Clostridium perfringens. A 3 × 2 factorial design was used, with 3 dietary formulations (0 or 90 mg/kg supplemental Zn from ZnSO4 or Zn proteinate, with or without challenge). On day 14, challenged birds were orally gavaged with approx. 5,000 Eimeria maxima sporulated oocysts, and on day 19 to 21 with C. perfringens (108 CFU/D). Productive performance was assessed at day 21 and 28. At 21 D, necrotic enteritis (NE) lesion severity, intestinal permeability, gene expression, and ileal and cecal microbiota were evaluated. An interaction of Zn source by challenge was observed for lesion score and mortality, wherein Zn supplementation decreased the degree of NE lesions (P = 0.02) and mortality due to NE (P = 0.008). In the jejunum, an interaction of Zn source by challenge was observed for the expression of IL-8 (P = 0.001) and INF-γ (P = 0.03), wherein the NE challenge upregulated their expression, but not in the Zn proteinate supplemented birds. Zn proteinate supplementation downregulated iNOS vs. ZnSO4 supplemented birds (P = 0.0003), and supplemental Zn downregulated TLR-2 (P = 0.05) and ZnT5 (P = 0.04), regardless of the source. In the ileal microbiota, Zn proteinate supplementation decreased the frequency of Lactobacillus (P = 0.01), and the challenge increased Enterobacteriaceae (P = 0.01). Dietary Zn decreased NE lesion severity and mortality due to NE; Zn proteinate led to lower expression of IL-8 and INF-γ in challenged birds which may be an indicative of a lessened inflammatory response. [ABSTRACT FROM AUTHOR]