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In the current study, we hypothesized that an increase in dietary ileal indigestible protein concentration induces an increase in hindgut nitrogen utilization and nitrogen excretion and a shift in fecal microbiota in growing pigs, when compared to pigs given a high total protein diet. Three diets were prepared: 1) standard protein diet based on corn and soybean meal, 2) high-indigestible protein diet in which autoclaved, low-digestible soybean meal replaced soybean meal in the first diet, and 3) high protein diet where the inclusion rate of soybean meal was greater than that of the other diets. The 3 diets were fed to 18 barrows that were fitted with T-cannula at the ileo-cecal junction (initial body weight = 63.4 ± 8.0 kg) in a randomized complete block design with body weight as a blocking factor. Pigs were individually housed in pens and the experiment lasted for 23 d. On days 7 and 21, fecal samples were collected by rectal massage for microbiota analysis. Grab samples of feces were collected on days 20 and 21, and ileal digesta were collected on days 22 and 23 for the determination of energy and nitrogen utilization. Lower apparent ileal digestibility of nitrogen in the high-indigestible protein diet containing autoclaved soybean meal resulted in greater ileal indigestible nitrogen concentration (P  < 0.05). Apparent total tract digestibility of nitrogen was lower (P  < 0.05), and correspondingly nitrogen concentration and daily fecal nitrogen output were greater (P  < 0.05) in the high-indigestible protein diet compared with the other diets. Apparent post-ileal digestibility and hindgut disappearance of nitrogen and gross energy were the greatest (P  < 0.05) in the high protein diet, whereas a statistical difference was not observed in those variables between the standard protein diet and the high-indigestible protein diet. Beta diversity metrics of feces in the high-indigestible protein diet on day 21 were different (q  < 0.05) from those in the other two diets, which indicates a shift in microbial communities. According to the results of the DESeq2, the direction of microbiota shift induced by the high-indigestible protein diet may have reduced fiber utilization in the hindgut. In conclusion, an increase in dietary ileal indigestible protein concentration increased fecal nitrogen excretion and shifted fecal microbial communities but did not increase nitrogen utilization in the hindgut. [ABSTRACT FROM AUTHOR]

Recent studies have shown that corn-derived cationic a-D-glucan nanoparticles, known as Nano-11, significantly increase the immune response when used as a vaccine adjuvant in mice and in pigs. Furthermore, the nanoparticles can be formulated with other immunostimulators such as poly(I:C), which further enhances the immune response. The current experiments were aimed at elucidating the mechanism of action of Nano-11 alone and in combination with poly(I:C). The effect of these adjuvants on porcine monocyte-derived dendritic cells (Mo-DCs) was determined by RNAsequencing, supplemented with flow cytometry, cytokine analysis, and Western blots. Adsorption of poly(I:C) to Nano-11 reduced its cytotoxicity for Mo-DCs. Exposure of Mo-DCs to Nano-11 and Nano-11/poly(I:C) induced differential expression of 979 and 2016 genes, respectively. Gene Ontology enrichment and KEGG pathway analysis revealed many changes in gene expression related to inflammation, innate immunity, immune response to infections, and metabolism. Nano-11 and Nano-11/poly(I:C) induced maturation of the Mo-DCs as indicated by increased expression of costimulatory molecules and MHC II. Increased expression of genes downstream of p38 MAPK activation revealed a role for this signaling pathway in the activation of Mo-DCs by the adjuvants. This was confirmed by Western blot and inhibition of TNF-secretion upon incubation with the p38 inhibitor SB203580. These experiments provide insights into the mechanism of action of the novel adjuvants Nano-11 and Nano-11/poly(I:C). [ABSTRACT FROM AUTHOR]

Energy values and amino acid (AA) digestibility of dried yeast (DY) and soybean meal (SBM) were determined in 2 experiments with growing pigs. Experiment 1 was conducted to determine the digestible energy (DE) and metabolizable energy (ME) in DY and SBM. Thirty barrows with a mean initial body weight (BW) of 20.6 kg (SD = 1.04) were assigned to 5 dietary treatments in a randomized complete block design with period and BW as blocking factors. A reference diet was prepared with corn, canola meal, and soybean oil as energy-contributing ingredients. Four additional diets were prepared by adding 5% and 10% DY or SBM at the expense of energy-contributing ingredients in the reference diet. The ratio of corn, canola meal, and soybean oil was kept consistent across the experimental diets. Each experimental period consisted of 5-d adaptation and 5-d quantitative collection of feces and urine. Test ingredient-associated DE or ME intake (kcal/d) was regressed against test ingredient intake [kg dry matter (DM)/d] to estimate the DE or ME in test ingredients as the slope of linear regression model. The DE in DY was estimated at 3,933 kcal/kg DM, which was not different from the estimated DE in SBM at 4,020 kcal/kg DM. Similarly, there was no difference between DY and SBM in the estimated ME (3,431 and 3,756 kcal/kg DM, respectively). Experiment 2 was conducted to determine the standardized ileal digestibility (SID) of AA in DY and SBM. Twenty-one barrows with a mean initial BW of 20.0 kg (SD = 1.31) were surgically fitted with T-cannulas at the distal ileum and assigned to 3 dietary treatments in a randomized complete block design with BW as a blocking factor. Two semi-purified diets containing DY or SBM as the sole nitrogen source and one nitrogen-free diet (NFD) were prepared. The NFD was used to estimate the basal ileal endogenous losses of CP and AA. Pigs were fed the 3 diets for 5 d as adaptation, followed by 2 d of feeding with ileal digesta collection. The SID of AA, except Gly and Pro, in DY was less (P < 0.05) than in SBM. The SID of indispensable AA in DY ranged from 64.1% for Thr to 85.2% for Arg, and those in SBM ranged from 83.9% for Thr to 91.8% for Arg. In conclusion, energy values of DY are not different from those of SBM, whereas AA in DY is less digestible than in SBM. The estimated DE and ME as well as the SID of AA in DY and SBM can be used in diet formulation for growing pigs using these ingredients. [ABSTRACT FROM AUTHOR]

Canola products including full-fat canola seeds (FFCS), canola meal (CM), and canola expellers (CE) have been used in diets for both broiler chickens and pigs. However, their ability to utilize the AA in canola products might be different from each other. Therefore, this study was conducted to compare the apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of CP and AA in broiler chickens and growing pigs fed FFCS, CM, and CE. Three diets were prepared to contain FFCS, CM, or CE as a sole source of nitrogen. A nitrogen-free diet was prepared. In Exp. 1, a total of 272 twenty-one-day-old male broiler chickens with an initial BW of 932 ± 80.6 g were assigned to diets in a randomized complete block design with BW as a blocking factor. After 5 d of feeding, birds were euthanized by sodium pentobarbital, and ileal digesta samples were collected from distal two-third of the ileum. In Exp. 2, 16 barrows were surgically fitted with T-cannulas at the distal ileum. After 8-d recovery period, pigs (initial BW = 18.9 ± 1.17 kg) were divided into 4 blocks based on BW and assigned to a quadruplicate 4 × 2 incomplete Latin Square design with 4 diets and 2 periods. Each period consisted of 5-d adaptation and 2-d ileal digesta collection periods. Data were analyzed as a 2 × 3 factorial treatment arrangement with effects of species (broiler chickens or pigs) and diets (FFCS, CM, or CE). There were interactions (P < 0.05) between species and experimental diets in the AID of all indispensable AA except for Lys. The AID of indispensable AA in FFCS for broiler chickens was greater (P < 0.05) than for pigs. Broiler chickens also had greater (P < 0.05) AID of Arg, His, Leu, Phe, and Val in CM compared with pigs; however, there were no differences in the AID of indispensable AA in CE between broiler chickens and pigs. The basal ileal endogenous losses of CP and AA, except Trp, in pigs were greater (P < 0.05) than in broiler chickens. There were also interactions (P < 0.05) between species and experimental diets in the SID of all indispensable AA except for Lys. Broiler chickens fed the diet containing FFCS had greater (P < 0.05) SID of indispensable AA compared with pigs fed the same diet; however, the SID of indispensable AA in CM or CE were not different between broiler chickens and pigs. In conclusion, differences in digestibility of AA in canola products were affected by nonruminant animal species. [ABSTRACT FROM AUTHOR]

Poultry meal (PoMe), a rendered product of slaughtered poultry carcasses, is widely used in swine and poultry diets because of its highly digestible protein and balanced amino acid profile. Rendering may reduce amino acid digestibility of PoMe because rendering can induce heat damage to PoMe, and the effect of heat damage on amino acid digestibility in PoMe may be different between broiler chickens and growing pigs. For this reason, the objective of this study was to determine the effect of autoclaving on standardized ileal digestibility (SID) of amino acid in PoMe fed to broiler chickens and growing pigs. Poultry meal from the same batch was autoclaved at 134°C for 0, 30, 60, 90, 120, 150, or 180 min for 7 samples. Eight experimental diets consisted of 7 diets containing each PoMe sample as a sole source of nitrogen and a nitrogen-free diet. In Exp. 1, 656 male broiler chickens (initial BW = 719 ± 97 g) at d 18 post hatching were assigned to the 8 diets in a randomized complete block design with BW as a blocking factor. On d 23, birds were euthanized by CO2 asphyxiation and dissected for the collection of ileal digesta. In Exp. 2, 16 barrows (initial BW = 23.3 ± 0.7 kg) surgically fitted with T-cannulas at the distal ileum were allotted to duplicate 8 × 4 incomplete Latin square design with the 8 diets and 4 periods. Each experimental period consisted of 5-d adaptation and 2-d ileal digesta collection periods. Data for Exp. 1 and 2 were pooled together as a 2 × 7 factorial treatment arrangement with the effects of species (i.e., pigs and broiler chickens) and autoclaving time (i.e., 0 to 180 min). An Interaction between species and linear effect of autoclaving time was observed (P < 0.05) in SID of nitrogen, arginine, and threonine in PoMe. To be specific, the linear decrease in ileal digestibility of nitrogen and those AA with increasing autoclaving time was greater in pigs compared with broiler chickens. The SID of AA both linearly and quadratically decreased (P < 0.05) as autoclaving time increased. The SID of isoleucine, leucine, methionine, phenylalanine, and tryptophan in PoMe was greater (P < 0.05) in growing pigs compared with broiler chickens regardless of autoclaving time. In conclusion, increasing autoclaving time decreases SID of amino acids in PoMe, and SID values in some indispensable amino acids are greater in growing pigs compared with broiler chickens. [ABSTRACT FROM AUTHOR]

The effect of changes in dietary ileal indigestible protein concentration may be more influential in the amount of nitrogen flowing to the large intestine compared with changes in total dietary protein concentration. For this reason, we hypothesized that an increase in dietary ileal indigestible protein concentration induces an increase in hindgut nitrogen utilization and nitrogen excretion and a shift in fecal microbiota in growing pigs, when compared with pigs given a high total protein diet. Three diets were prepared: 1) standard protein diet based on corn and soybean meal, 2) high-indigestible protein diet in which autoclaved soybean meal replaced normal soybean meal in the first diet, and 3) high protein diet where the inclusion rate of soybean meal was greater than that of the other diets. T-cannulated barrows (n = 18; initial BW = 63.4 ± 8.0 kg) were allotted to the 3 diets in a randomized complete block design with BW as a blocking factor. Pigs were individually housed in pens and the experiment lasted for 23 days. On d 7 and 21, fecal samples were collected by rectal massage for microbiota analysis. Grab samples of feces were collected on d 20 and 21, and ileal digesta were collected on d 22 and 23 for the determination of energy and nitrogen utilization. Energy and nitrogen utilization data were analyzed using the MIXED procedure of SAS using a pig as the experimental unit and a model that included diet as a fixed variable and block as a random variable. For microbiome analysis, R was used. Alpha and beta diversity metrics were analyzed and the difference in abundance of the genus was determined using the DESeq2 function. The high-indigestible protein diet achieved decreased apparent ileal digestibility of nitrogen and resulted in greater ileal indigestible nitrogen concentration (P < 0.05). Apparent total tract digestibility of nitrogen was less (P < 0.05), and correspondingly fecal nitrogen concentration and daily fecal nitrogen output were greater (P < 0.05) in the high-indigestible protein diet. Apparent post-ileal digestibility and hindgut disappearance of nitrogen and gross energy were the greatest (P < 0.05) in the high protein diet. Beta diversity metrics of feces in the high-indigestible protein diet on d 21 were different (q < 0.05) from those in the other two diets, which indicates a shift in fecal microbiota. According to the DESeq2 results, the direction of the microbiota shift induced by the high-indigestible protein diet may have reduced hindgut fiber utilization. In conclusion, an increase in dietary ileal indigestible protein increased nitrogen excretion and shifted fecal microbial communities but did not increase hindgut nitrogen utilization. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to determine the influence of sources or concentrations of dietary fiber in nitrogen-free diets (NFD) on basal ileal endogenous losses (BEL) of amino acids (AA) and subsequent standardized ileal digestibility (SID) of AA in feed ingredients for pigs derived from such BEL. In Exp. 1, 20 pigs (initial body weight = 46.5 ± 2.97 kg) were assigned to five diets in a quadruplicate 5 × 2 incomplete Latin square design with two periods. Three NFD containing cellulose (insoluble and fermentable fiber), inulin (soluble and fermentable fiber), or carboxymethyl cellulose (CMC; soluble and non-fermentable fiber) at 40 g/kg plus two diets containing soybean meal (SBM) or wheat distillers' dried grains (WDDG) as the sole source of nitrogen were prepared. Pigs fed NFD containing CMC had greater (P < 0.05) BEL of AA, except for Arg and Pro, than those fed the other NFD. The SID of most AA in SBM and WDDG corrected by BEL of AA from NFD containing CMC were greater (P < 0.05) than those corrected by BEL of AA from the other NFD. Experiment 2 was conducted with 21 barrows (initial body weight = 34.1 ± 2.57 kg) assigned to seven diets in a triplicate 7 × 3 incomplete Latin square design with 3 periods. Seven diets consisted of three NFD containing 4, 8, or 12 g/kg cellulose and four diets containing corn, wheat, SBM, or canola meal as the sole source of nitrogen. There was no difference in the BEL of AA, except for Pro, among pigs fed NFD with increasing concentration of cellulose. The SID of AA in test ingredients were not affected by BEL of AA from NFD containing increasing concentration of cellulose. In conclusion, chemical characteristics of dietary fiber, but not concentration, affect the BEL of AA in pigs. [ABSTRACT FROM AUTHOR]

Adjuvant potential of positively charged corn-derived nanoparticles (Nano-11) was earlier revealed in mice. We evaluated its adjuvant role to electrostatically adsorbed inactivated/killed swine influenza virus antigen (KAg) (Nano-11 + KAg) in pigs. Nano-11 facilitated the uptake of KAg by antigen presenting cells and induced secretion of proinflammatory cytokines. In pigs vaccinated by an intranasal mist containing Nano-11 + KAg, expression of T-helper 1 and T-helper 2 transcription factors and secretion of cross-reactive influenza antigen-specific mucosal IgA in the nasal cavity were observed. The enhanced frequencies of IFN-γ positive T-helper and cytotoxic T-cells in Nano-11 + KAg-vaccinates after heterologous virus challenge were also observed. Clinically, slightly reduced influenza signs and pneumonic lesions, with mild reduction in virus load in the respiratory tract of vaccinates were observed. In pigs immunized with Nano-11 adsorbed ovalbumin administered by intramuscular (IM) route, enhanced IgG1 and IgG2 antibodies were detected in serum. Thus, Nano-11 vaccine delivery system confers adjuvant effect in pigs., (Copyright © 2018 Elsevier Inc. All rights reserved.)