Effect of potential multimicrobe probiotic product processed by high drying temperature and antibiotic on performance of weanling pigs

In this study, the effect of a potential multimicrobe probiotic subjected to high-temperature drying was investigated. Potential multimicrobe probiotics produced by solid substrate fermentation were dried at low (LT, 40°C for 72 h) or high (HT, 70°C for 36 h) temperature. In Exp. 1, 288 weaned pigs (BW, 6.43 ± 0.68 kg) were allotted to 4 treatments on the basis of BW (4 pens per treatment with 18 pigs in each pen). Dietary treatments were negative control (NC; basal diet without any antimicrobial), positive control (PC; basal diet + 0.1% chlortetracycline), basal diet with 0.3% probiotic LT, and basal diet with 0.3% probiotic HT. Diets were fed in 2 phases, phase I (d 0 to 14) and phase II (d 15 to 28); and growth performance, apparent total tract digestibility (ATTD, d 28), and fecal microflora (d 14 and 28) were evaluated. Over the 28-d trial, pigs fed PC and probiotic diets had greater ADG (P < 0.001), ADFI (P < 0.05), and G:F (P < 0.01) than pigs fed NC diet. The ATTD of DM and GE was greater (P < 0.05) in pigs fed probiotic diets when compared with pigs fed the NC diet. At d 28, fewer Clostridia (P < 0.01) were identified in the feces of pigs fed PC and probiotic diets than pigs fed the NC diet. However, the performance, ATTD of DM and GE, and fecal Clostridia population were similar among pigs fed probiotic LT and HT diets. In Exp. 2, 288 weaned pigs (initial BW, 5.84 ± 0.18 kg) were allotted to 4 treatments in a 2 × 2 factorial arrangement on the basis of BW. The effects of 2 levels of probiotic HT (0.30 or 0.60%), each with or without antibiotic (chlortetracycline, 0 or 0.1%), on performance, ATTD, intestinal morphology, and fecal and intestinal microflora were investigated. Feeding of 0.60% probiotic HT diet improved (P < 0.05) overall ADG, ATTD of DM and GE, and Lactobacillus population in the feces and intestine, and reduced the population of Clostridium and coliforms in feces (d 14) and ileum. Inclusion of antibiotic improved (P < 0.05) the overall ADG, ADFI, and ATTD of DM at d 14 and reduced fecal Clostridium population at d 28. Increased (P < 0.05) villus height at jejunum and ileum, and villus height:crypt depth at the ileum was noticed in pigs fed 0.60% probiotic HT and antibiotic diets. In conclusion, high drying temperature had no effect on the efficacy of potential multimicrobe probiotic product. However, the probiotic product dried at high temperature was more effective at 0.60% inclusion, whereas inclusion of an antibiotic improved pig performance but did not show any interaction with probiotics.     

Effects of exogenous enzyme supplementation to corn- and soybean meal-based or complex diets on growth performance, nutrient digestibility, and blood metabolites in growing pigs

Two experiments were conducted to determine the effects of dietary supplementation of exogenous enzymes on growth performance, apparent total tract digestibility (ATTD) of energy and nutrients, blood metabolites, fecal VFA, and fecal ammonia-N in growing pigs (Sus scrofa) fed a corn (Zea mays L.)- and soybean [Glycine max (L.) Merr.] meal (SBM)-based diet. In Exp. 1, 240 growing barrows (initial BW: 55.6 ± 0.9 kg) were randomly allotted to 5 treatments on the basis of BW. There were 4 replicates in each treatment with 12 pigs per replicate. The 5 treatments consisted of a corn-SBM-based control diet and 4 additional diets were similar to the control diet, with the exception that 0.05% β-mannanase (M), α-amylase + β-mannanase (AM), β-mannanase + protease (MPr), or α-amylase + β-mannanase + protease (AMP) was added to the diets, which were fed for 28 d. Pigs fed the AM, MPr, or AMP diet had greater (P < 0.05) ADG than pigs fed the control diet. Pigs fed the AMP diet also had greater (P < 0.05) ADG than pigs fed the M, AM, or MPr diet. Pigs fed the AMP diet had greater (P < 0.05) G:F than pigs fed the control diet. The G:F of the pigs fed the M, AM, or MPr diet were not different (P > 0.05) from the G:F in pigs fed the AMP or control diet. The ADFI, ATTD of nutrients, blood metabolites, and fecal VFA and ammonia-N concentrations were not different among treatments. In Exp. 2, 192 growing barrows (initial BW: 56.9 ± 1.0 kg) were allotted to 4 treatments. There were 4 replicates in each treatment with 12 pigs per replicate. Pigs were fed a corn-SBM-based diet (CSD) or a complex diet (CD) that contained corn, SBM, 3% rapeseed (Brassica napus L.) meal, 3% copra (Cocos nucifera L.) meal, and 3% palm (Elaeis guineensis Jacq.) kernel meal. Each diet was prepared without exogenous enzymes or with 0.05% AMP and all diets were fed for 28 d. The ADG and G:F of pigs fed the CSD were greater (P < 0.05) than pigs fed the CD. However, the type of diet had no effect on the ATTD of nutrients, blood metabolites, or fecal VFA and ammonia-N, and there was no diet × enzyme interaction for any of the measured variables. Supplementation of diets with exogenous enzymes resulted in greater (P < 0.05) ADG, G:F, ATTD of DM, GE, and CP, and blood urea nitrogen (BUN) concentration. These results indicate that supplementation of 0.05% of AMP enzymes to a corn-SBM diet or a complex diet may improve the performance of growing pigs.     

The effects of pharmacological levels of zinc,diet acidification,and dietary crude protein on growth performance in nursery pigs

This experiment was conducted to evaluate potential replacements for pharmacological levels of Zn (provided by Zn oxide), such as diet acidification (sodium diformate) and low dietary crude protein (CP: 21 vs 18%) on nursery pig performance and fecal dry matter (DM). A total of 360 weaned pigs (Line 200 × 400, DNA, Columbus, NE; initially 5.90 ± 0.014 kg) were used in a 42-d growth study. Pigs were weaned at approximately 21 d of age and randomly assigned to pens (five pigs per pen). Pens were then allotted to one of eight dietary treatments with nine pens per treatment. Experimental diets were fed in two phases: phase 1 from weaning to day 7 and phase 2 from days 7 to 21, with all pigs fed the same common diet from days 21 to 42. The eight treatment diets were arranged as a 2 × 2 × 2 factorial with main effects of Zn (110 mg/kg from days 0 to 21 or 3,000 mg/kg from days 0 to 7, and 2,000 mg/kg from days 7 to 21), diet acidification, (without or with 1.2% sodium diformate), and dietary CP (21% or 18%, 1.40% and 1.35% in phases 1 and 2 vs. 1.20% standardized ileal digestible Lys, respectively). Fecal samples were collected weekly from the same three pigs per pen to determine DM content. No 2- or 3-way interactions (P > 0.05) were observed throughout the 42-d study for growth performance; however, there was a Zn × acidifier × CP interaction (P < 0.05) for fecal DM on day 7 and for the overall average of the six collection periods. Reducing CP without acidification or pharmacological levels of Zn increased fecal DM, but CP had little effect when ZnO was present in the diet. From days 0 to 21, significant (P < 0.05) main effects were observed where average daily gain (ADG) and gain:feed (G:F) increased for pigs fed pharmacological levels of Zn, sodium diformate, or 21% CP (P < 0.065). In the subsequent period (days 21 to 42) after the experimental diets were fed, there was no evidence of difference in growth performance among treatments. Overall (days 0 to 42), main effect tendencies were observed (P < 0.066) for pigs fed added Zn or sodium diformate from days 0 to 21, whereas pigs fed 21% CP had greater G:F than those fed 18% CP. Pig weight on day 42 was increased by adding Zn (P < 0.05) or acidifier (P < 0.06) but not CP. In summary, none of the feed additives had a major influence on fecal DM, but dietary addition of pharmacological levels of Zn or sodium diformate independently improved nursery pig performance.     

Nutrient digestibility of extruded canola meal in ileal-cannulated growing pigs and effects of its feeding on diet nutrient digestibility and growth performance in weaned pigs

Canola meal (CM) contains less crude protein (CP) and more fiber and anti-nutritional factors such as glucosinolates than soybean meal (SBM) and consequently has a lower nutrient digestibility. Therefore, processing strategies that may increase the feeding value of CM warrant study. In two experiments, the effects of extrusion of Brassica napus CM on apparent (AID) and standardized ileal digestibility (SID) of amino acids (AA), apparent total tract digestibility (ATTD) of gross energy (GE) in growing pigs, and growth performance and diet digestibility in weaned pigs were assessed. Solvent-extracted CM was extruded using a single-screw extruder at three screw speeds: 250 (CM-250), 350 (CM-350), or 450 (CM-450) rpm. In exp. 1, in a double 4 × 4 Latin square, eight ileal-cannulated barrows (initial body weight [BW], 68.1 kg) were fed corn starch-based diets containing 50% CM or extruded CM. The CM sample contained 43.2% CP, 33.2% total dietary fiber (TDF), and 8.9 µmol of total glucosinolates/g on a dry matter (DM) basis. Extrusion increased (P < 0.05) the AID of CP, reduced (P < 0.05) apparent hindgut fermentation of CP, and decreased (P < 0.05) predicted net energy (NE) value of diets. Extrusion increased diet AID and CM SID of most indispensable AA by 3.1 to 5.3%-units. In exp. 2, 200 weaned pigs (initial BW, 8.3 kg) were fed diets containing 20% SBM, CM, or extruded CM starting 2 wk postweaning for 3 wk. The CM sample contained 42.7% CP, 28.3% TDF, and 5.3 µmol total glucosinolates/g DM. Wheat-based diets provided 2.3 Mcal NE/kg and 5.1 g SID Lys/Mcal NE. Dietary inclusion of extruded CM replacing SBM decreased (P < 0.05) diet ATTD of DM, GE and CP, and DE value. Average daily feed intake, average daily gain (ADG), and gain:feed (G:F) of pigs did not differ between extruded CM and SBM diets and were not affected by extrusion, but increasing extruder screw speed linearly increased (P < 0.05) ADG for day 1 to 7 and G:F for the entire trial. In conclusion, extrusion increased diet AID and CM SID of AA but not DE and predicted NE values of CM. However, increasing extruder speed did not further increase the SID of most of the AA of CM in growing pigs. Dietary inclusion of 20% CM or extruded CM did not affect the growth performance in weaned pigs.     

Nutrient digestibility and fecal characteristics,microbiota, and metabolites in dogs fed human-grade foods

Human-grade (HG) pet foods are commercially available, but they have not been well studied. Our objective was to determine the apparent total tract digestibility (ATTD) of HG pet foods and evaluate their effects on fecal characteristics, microbiota, and metabolites, serum metabolites, and hematology of dogs. Twelve dogs (mean age = 5.5 ± 1.0; BW = 11.6 ± 1.6 kg) were used in a replicated 4 × 4 Latin square design (n = 12/treatment). The diets included 1) Chicken and Brown Rice Recipe (extruded; Blue Buffalo); 2) Roasted Meals Tender Chicken Recipe (fresh; Freshpet); 3) Beef and Russet Potato Recipe (HG beef; JustFoodForDogs); and 4) Chicken and White Rice Recipe (HG chicken; JustFoodForDogs). Each period consisted of 28 d, with a 6-d diet transition phase, 16 d of consuming 100% of the diet, a 5-d phase for fecal collection, and 1 d for blood collection. All data were analyzed using the Mixed Models procedure of SAS 9.4. Dogs fed the extruded diet required a higher (P < 0.05) daily food intake (dry matter basis, DMB) to maintain BW. The ATTD of dry matter (DM), organic matter (OM), energy, and acid-hydrolyzed fat (AHF) were greater (P < 0.05) in dogs fed the HG diets than those fed the fresh diet, and greater (P < 0.05) in dogs fed the fresh diet than those fed the extruded diet. Crude protein ATTD was lower (P < 0.05) for dogs fed the extruded diet than those fed all other diets. Dogs fed the extruded diet had greater (P < 0.05) fecal output (as-is; DMB) than dogs fed fresh (1.5–1.7 times greater) or HG foods (2.0–2.9 times greater). There were no differences in fecal pH, scores, and metabolites, but microbiota were affected by diet. Dogs fed HG beef had higher (P < 0.05) relative abundance of Bacteroidetes and lower (P < 0.05) relative abundance of Firmicutes than dogs fed the fresh or HG chicken diets. The Actinobacteria, Fusobacteria, Proteobacteria, and Spirochaetes phyla were unchanged (P > 0.05), but diet modified the relative abundance of nearly 20 bacterial genera. Similar to previous reports, these data demonstrate that the fecal microbiota of dogs fed HG or fresh diets is markedly different than those consuming extruded diets, likely due to ingredient, nutrient, and processing differences. Serum metabolites and hematology were not greatly affected by diet. In conclusion, the HG pet foods tested resulted in significantly reduced fecal output, were highly digestible, maintained fecal characteristics, serum chemistry, and hematology, and modified the fecal microbiota of dogs.     

Effect of mannan oligosaccharides and fructan on growth performance, nutrient digestibility, blood profile, and diarrhea score in weanling pigs

A total of 150 weanling pigs [(Yorkshire × Landrace) × Duroc] with an average BW of 7.22 ± 0.80 kg (21 d of age) were used in a 28-d trial to determine the effects of dietary fructan and mannan oligosaccharides on growth performance, nutrient digestibility, blood profile, and diarrhea score in weanling pigs. Pigs were allotted randomly to 1 of 5 dietary treatments: 1) negative control (NC), basal diet; 2) positive control (PC), NC + 0.01% apramycin (165 mg/kg); 3) NC + 0.1% fructan (FC); 4) NC + 0.1% mannan oligosaccharide source (MO); and 5) NC + 0.05% fructan + 0.05% mannan oligosaccharide source (FM). There were 3 replications per treatment with 10 pigs per pen (5 barrows and 5 gilts). From d 0 to 14, ADG and ADFI of pigs fed the PC, MO, and FM diets were greater (P < 0.05) than pigs fed the NC diet. From d 15 to 28, there were no differences (P > 0.05) in ADG, ADFI, and G:F. During the overall period (d 0 to 28), pigs fed the MO diet had a greater ADG than pigs fed the NC diet (P < 0.05). Pigs fed the PC and MO diets increased ADFI (P < 0.05) compared with pigs fed the NC diet. However, no differences were detected among dietary treatments in G:F during the overall experimental period. On d 14, the apparent total tract digestibility (ATTD) of DM and N in pigs fed the PC, MO, and FM diets was greater (P < 0.05) than pigs fed the NC diet. The ATTD of DM increased (P < 0.05) in pigs fed the MO and FM diets compared with pigs fed the FC diet. However, at the end of the experiment, pigs fed the FM diet had a greater (P < 0.05) ATTD of DM compared with pigs fed the NC diet. Additionally, there were no differences in IgG, red blood cells, white blood cells, and lymphocyte counts among dietary treatments on d 0, 14, or 28. The diarrhea score in pigs fed the MO diet was reduced (P < 0.05) compared with pigs fed the NC diet. In conclusion, mannan oligosaccharides have a beneficial effect on growth performance and nutrient digestibility in weanling pigs. Furthermore, mannan oligosaccharides can decrease diarrhea score in weanling pigs.     

Growth performance and gut health of Escherichia coli–challenged weaned pigs fed canola meal-containing diet

An experiment was conducted to evaluate the effects of including canola meal (CM) in diets for weaning pigs challenged with a F18 strain of Escherichia coli on growth performance and gut health. A total of 36 individually housed weaned pigs (initial body weight [BW] = 6.22 kg) were randomly allotted to one of the three diets (12 pigs/diet). The three diets were corn–soybean meal (SBM)-based basal diet (control diet) and the basal diet with 0.3% zinc oxide, 0.2% chlortetracycline, and 0.2% tiamulin (antibiotic diet) or with 20% CM diet. The diets were fed in two phases: Phase 1: days 0 to 7 and Phase 2: days 7 to 20. All pigs were given an oral dose of 2 × 10⁹ CFU of F18 strain of E. coli on day 7. Fecal score was assessed daily throughout the trial. Dietary antibiotics increased (P < 0.05) overall average daily gain (ADG) and average daily feed intake (ADFI) compared by 48% and 47%, respectively. Dietary CM increased (P < 0.05) overall ADG and ADFI by 22% and 23%, respectively; but the ADG and ADFI values for CM-containing diet did not reach those for the antibiotics-containing diet. Dietary antibiotics reduced (P < 0.05) fecal score; however, dietary CM unaffected fecal score. Dietary antibiotics decreased (P < 0.05) liver weight per unit live BW by 16% at day 20, whereas dietary CM did not affect liver weight per unit live BW (29.2 vs. 28.6). Also, dietary antibiotics increased (P < 0.05) serum triiodothyronine and tetraiodothyronine levels for day 14, whereas dietary CM did not affect the serum level of these hormones. Dietary antibiotics reduced (P < 0.05) the number white blood cells and neutrophils by 38% and 43% at day 20, respectively, whereas dietary CM tended to reduce (P = 0.09) the number white blood cells by 19% at day 20. The number white blood cells for CM diet tended to be greater (P < 0.10) than that for antibiotics diet. The dietary antibiotics decreased (P < 0.05) the concentration of individual volatile fatty acids and hence of total volatile fatty acid in cecum by 61% at day 20, whereas dietary CM decreased (P < 0.05) cecal butyric acid concentration by 61% and tended to reduce (P < 0.10) total volatile fatty acid concentration by 30% at day 20. In conclusion, the dietary inclusion of 20% CM improved ADG and tended to reduce white blood cell counts. Thus, inclusion of CM in antibiotics-free corn-SBM-based diets for weaned pigs that are challenged with F18 strain of E. coli can result in their improved performance partly through a reduction of the inflammatory response.     

Effects of graded levels of xylo-oligosaccharides on growth performance,serum parameters,intestinal morphology,and intestinal barrier function in weaned piglets

The objective of this study was to investigate the effects of xylo-oligosaccharides (XOSs) supplementation on growth performance, serum parameters, small intestinal morphology, intestinal mucosal integrity, and immune function in weaned piglets. A total of 240 weaned piglets with an average body weight (BW) of 8.82 ± 0.05 kg (28 d of age) were assigned randomly to four dietary treatments in a 28-d trial, including a control (CON) diet and three diets with XOS supplementation at the concentration of 100 (XOS100), 500 (XOS500), and 1,000 (XOS1000) mg/kg. There were four replicates per treatment with 15 pigs per pen. From day 1 to 14, there were no differences (P > 0.05) in average daily gain (ADG), average daily feed intake, and gain to feed ratio (G:F) during the different treatments. The different doses of XOSs showed a quadratic effect on BW on day 28, ADG, and G:F on day 1 to 28 of piglets (P < 0.05). From day 15 to 28, ADG of pigs fed the XOS500 diet was higher (P < 0.05) than pigs fed the CON diet. During the overall period (day 1 to 28), pigs fed the XOS500 diet had a higher BW, ADG, and G:F than pigs fed the CON diet (P < 0.05). In addition, compared with the CON group, the XOS500 group had significantly higher serum total antioxidant capacity, total superoxide dismutase and catalase levels, and lower malondialdehyde levels on days 14 and 28 (P < 0.05). The serum immunoglobulin G (IgG) concentration in the XOS500 group was also significantly higher compared with the CON group on days 14 and 28 (P < 0.05). However, serum immunoglobulin A and immunoglobulin M were not affected by the dietary treatments. Supplementation of XOS500 to the feed significantly increased the villus height (VH) and VH to crypt depth ratio in the jejunum and ileum in comparison with the CON and XOS1000 groups. Moreover, the XOS500 group significantly elevated the expression levels of occludin and zonula occludens protein-1 in the ileum compared with the CON group. The ileal interleukin (IL)-1β, IL-8, and interferon (IFN)-γ mRNA expression levels in the XOS100 and XOS500 groups were markedly lower than in the CON group. In contrast, the ileal IL-10 mRNA expression levels were remarkably higher in the XOS500 than in the CON group. In conclusion, XOSs have a beneficial effect on growth performance by improving serum antioxidant defense system, serum IgG, small intestinal structure, and intestinal barrier function in weaned piglets.     

Growth performance,immune status,gastrointestinal tract ecology,and function in nursery pigs fed enzymatically treated yeast without or with pharmacological levels of zinc

Growth performance and physiological responses of nursery piglets when fed enzymatically treated yeast (HY40) and pharmacological ZnO alone or in combination were investigated. A total of 144 pigs (21 d old, BW 7.32 ± 0.55 kg) were placed in 36 pens (4 pigs/pen). Pigs were randomly assigned to one of four dietary treatments (n = 9): 1) control corn-wheat-soybean meal diet (control), 2) control + HY40 (HY40), 3) control + (ZnO) and 4) control + HY40 + ZnO (HY40+ZnO). Inclusion of HY40 and ZnO was 0.5% and 3,000 ppm in phase I (days 0 to 14), respectively, and halved in phase II (days 15 to 42). All diets contained 0.2% TiO₂ for determination of apparent total tract digestibility (ATTD) of components. Body weight and feed disappearance were recorded weekly. One pig per pen was killed for organ weights, blood, and tissue samples on day 14. Except for phase II, when HY40 + ZnO pigs had greater average daily feed intake (P = 0.004) than all other treatments, there were no (P > 0.05) interactions between HY40 and ZnO on growth performance. Pigs fed HY40 or ZnO containing diets were heavier (P < 0.05) than pigs fed without by the end of the study. On day 14, pigs fed additives exhibited higher (P ≤ 0.009) ATTD of dry matter (DM) and gross energy (GE) than control pigs. On day 28, pigs fed control, HY40, and HY40 + ZnO had greater (P ≤ 0.022) ATTD of DM, crude protein, and GE than piglets fed ZnO only. Pigs fed HY40 + ZnO had lower ileal digesta Escherichia coli concentration (P < 0.05) than HY40 and control pigs. Ileal digesta of pigs fed ZnO diets had higher lactobacillus to E. coli ratio (1.44 vs. 1.20; P = 0.001), exhibited higher concentrations of acetic (P = 0.01) and butyric acid (P = 0.01) but lower lactic (P = 0.02) and total short chain fatty acids (P = 0.033) than pigs fed non-ZnO diets. Greater (P < 0.05) mRNA expression of nutrient transporters, tight junction proteins, and fecal excretion of zinc (Zn) was observed in ZnO pigs relative to non-ZnO pigs. Pigs fed HY40 diets had greater (P = 0.002) villus height to crypt depth ratio (VH:CD) than non-HY40 pigs. The concentration of plasma IgA was higher (P = 0.04) in HY40 + ZnO pigs relative to other pigs, whereas HY40 pigs showed higher (P < 0.001) jejunal IgA than non-HY40 pigs. Although the mode of action of HY40 and ZnO differed, the present study indicated that HY40 improved growth performance and jejunal function and immunity, making HY40 an effective alternative to pharmacological ZnO in nursery pigs feeding programs.     

Effects of feeding diets containing low crude protein and coarse wheat bran as alternatives to zinc oxide in nursery pig diets

Two experiments were conducted to determine the effects of crude protein (CP) level in diets containing coarse wheat bran (CWB) with or without pharmacological levels of Zn (provided by zinc oxide: ZnO) on growth performance and fecal DM of nursery pigs. In experiment 1, 360 barrows (Line 200 × 400, DNA, Columbus, NE, initially 5.6 kg) were allotted to 1 of 6 dietary treatments from d 0 to 21 after weaning with 5 pigs per pen and 12 pens per treatment. Treatments included a positive control diet (21% CP) with 3,000 mg/kg Zn in phase 1 and 2,000 mg/kg in phase 2; negative control (21% CP) with 110 mg/kg added Zn, and 4 diets containing 4% CWB and 110 mg/kg added Zn formulated to contain 21%, 19.5%, 18%, or 16.5% CP. The 2 control diets and 21% CP CWB diet contained 1.40% standardized ileal digestible (SID) Lys in phase 1 and 1.35% SID Lys in phase 2, while the 19.5%, 18%, and 16.5% CP diets contained 1.33, 1.25 and 1.20% Lys, respectively, in both phases. Pigs fed the positive control diet containing pharmacological ZnO had increased (P < 0.05) ADG and G:F compared with the negative control and the 21% CP CWB diet. Reducing CP (concurrently with SID Lys) in diets containing CWB decreased ADG and G:F (linear, P = 0.002); however, fecal DM increased (linear, P = 0.005). In experiment 2, two groups of 300 and 350 pigs, initially 7.0 and 6.2 kg, respectively, were used with 5 pigs per pen and 26 pens per treatment. The objective was to determine if adding back essential AA would improve growth performance of pigs fed the low CP diets. All dietary treatments were fed for 13 days, contained 4% CWB, and consisted of: (1) positive control with 2,000 mg/kg of Zn and 21% CP (1.35% SID Lys); (2) no ZnO and 21% CP; and 3 diets with no ZnO formulated to 18% CP and (3) 1.2% SID Lys; (4) 1.35% SID Lys by the addition of feed grade amino acids (AA), and (5) diet 4 with non-essential amino acids (NEAA; Gly and Glu). Pigs fed 21% CP with ZnO had increased (P = 0.001) ADG compared to those fed 18% CP (1.35% SID Lys) with high levels of feed grade amino acids or those fed the reduced SID Lys (1.2%) diet. Overall, G:F was improved (P < 0.001) for pigs fed 21% CP diets and those fed the 18% CP diet with NEAA compared to pigs fed 1.2% SID Lys and pigs fed high levels of feed grade amino acids. Fecal DM was increased for pigs fed the reduced SID Lys diet. In summary, pharmacological levels of Zn improve pig growth performance, but reducing CP (and subsequently SID Lys) decreased nursery pig growth performance.     

Effect of a novel consensus bacterial 6-phytase variant in grower pigs fed corn-soybean meal-based diets formulated with a full nutrient matrix and no added inorganic phosphorus

The capacity of a novel consensus bacterial 6-phytase variant (PhyG) to entirely replace dietary inorganic phosphorus (Pi) source in grower pigs fed diets with reduction of calcium (Ca), net energy (NE), and digestible amino acids (AA) was evaluated, using growth performance and apparent total tract digestibility (ATTD) of nutrients as outcome measures. A total of 352 mixed-sex pigs (initial BW 23.4 kg) were randomized to 4 treatments, 8 pigs/pen, and 11 pens/treatment. Diets were corn-soybean meal-based and formulated by phase (grower 1, 25 to 50 and grower 2, 50 to 75 kg BW). The positive control diet (PC) provided adequate nutrients and a negative control diet (NC) was formulated without Pi (1.2 g/kg ATTD P) and reduced in Ca (-0.12 to -0.13 percentage points), NE (-32 kcal/kg), and digestible essential AA (-0.004 to -0.026 percentage points) vs. PC. Two further treatments comprised the NC plus 500 or 1,000 FTU/kg of PhyG. Data were analyzed by ANOVA, mean contrasts and orthogonal polynomial regression. Nutrient reductions in the NC reduced (P < 0.05) average daily gain (ADG) during grower 1 and overall (73 to 136 d of age), increased (P < 0.05) feed conversion ratio (FCR) during grower 1 and overall and tended to reduce (P < 0.1) average daily feed intake (ADFI) during grower 2 and overall, vs. PC. Phytase supplementation improved (P < 0.05) FCR during grower 1, ADG during grower 2 and overall, ATTD of DM and P, and tended to improve DE (P = 0.053) in a linear dose-dependent manner. PhyG at 1,000 FTU/kg resulted in growth performance (all measures, all phases) equivalent to PC. The findings demonstrate that PhyG at 1,000 FTU/kg totally replaced Pi in complex grower pig diets containing industrial co-products, compensated a full nutrient matrix reduction and maintained performance.     

Intrinsic phytase in hybrid rye increases the digestibility of phosphorus in corn and soybean meal in diets fed to growing pigs

An experiment was conducted to test the hypothesis that inclusion of hybrid rye in diets containing corn and soybean meal (SBM) without or with microbial phytase improves the apparent total tract digestibility (ATTD) and the standardized total tract digestibility (STTD) of P because of the intrinsic phytase activity in hybrid rye. Forty-eight growing barrows (initial body weight: 39.5 ± 7.7 kg) were allotted to six diets. A basal diet containing corn and SBM; a rye-based diet; and a diet containing corn, SBM, and rye were formulated. Each diet was formulated without and with microbial phytase (500 units/kg of diet) for a total of six diets. Fecal samples were collected for 4 d following a 5-d adaptation period according to the marker-to-marker procedure. Results indicated that no interactions between diets and concentration of phytase were observed for any of the response criteria measured. The ATTD and STTD of P and the ATTD of Ca differed (P < 0.05) among diets, but regardless of diet, the concentration of P in feces was reduced (P < 0.05) by adding microbial phytase to the diets. As a consequence, microbial phytase increased (P < 0.05) ATTD and STTD of P, and the ATTD of Ca was also increased (P < 0.05) by the use of microbial phytase. Measured values for the ATTD and STTD of P in the diets containing corn, SBM, and hybrid rye without or with phytase were greater (P < 0.05) than values that were predicted based on the ATTD and STTD of P for the corn–SBM and the hybrid rye diet. The observation that STTD predicted from the individual ingredients underestimated the STTD of P in the mixed diet indicates that the intrinsic phytase in hybrid rye resulted in increased digestibility of the P in the corn and SBM included in the corn–SBM–hybrid rye diet. In conclusion, microbial phytase increased the ATTD and STTD of P and the ATTD of Ca regardless of feed ingredients used in diets fed to pigs. In addition, the intrinsic phytase from hybrid rye increased the ATTD and STTD of P in corn and SBM.     

Effects of increasing choice white grease in corn- and sorghum-based diets on growth performance, carcass characteristics, and fat quality characteristics of finishing pigs

A total of 120 pigs (60 barrows and 60 gilts; TR4 × PIC 1050; 54.4 kg initial BW) were used in an 83-d study to evaluate the effects of added fat in corn- and sorghum-based diets on growth performance, carcass characteristics, and carcass fat quality. Treatments were arranged in a 2 × 3 factorial with grain source (corn or sorghum) and added fat (0, 2.5, or 5% choice white grease; CWG) as factors. There were 2 pigs (1 barrow and 1 gilt) per pen and 10 replicate pens per treatment. Pigs and feeders were weighed on d 14, 22, 39, 53, 67, and 83 to calculate ADG, ADFI, and G:F. At the end of the trial, pigs were slaughtered and jowl fat and backfat samples were collected and analyzed for fatty acid profile. No interactions were observed for growth performance. Pigs fed sorghum-based diets had greater (P < 0.01) ADG than pigs fed corn-based diets. Adding CWG improved (linear, P < 0.01) ADG. Pigs fed corn-based diets tended to have greater (P < 0.09) carcass yield, 10th-rib backfat, and percentage lean than pigs fed sorghum-based diets. Adding CWG increased (linear, P = 0.02) 10th-rib backfat, tended to increase (linear, P = 0.08) HCW, and tended to decrease (linear, P = 0.07) percentage lean. There was no grain source × fat level interaction for iodine value (IV) in backfat, but an interaction (P = 0.03) was observed for IV in jowl fat. Adding CWG increased (P < 0.01) IV in jowl fat for pigs fed sorghum- and corn-based diets; however, the greatest increase was between 0 and 2.5% CWG in sorghum-based diets and between 2.5 and 5% CWG in corn-based diets. Pigs fed corn-based diets had less (P = 0.01) C18:1 cis-9 and MUFA but greater (P = 0.01) C18:2n-6, PUFA, and backfat IV than pigs fed sorghum-based diets. Increasing CWG in the diet increased (linear, P = 0.01) backfat IV. Of the 2 fat depots, backfat generally had a reduced IV than jowl fat. In summary, feeding sorghum-based diets reduced carcass fat IV and unsaturated fats compared with corn-based diets. As expected, adding CWG increased carcass fat IV regardless of the cereal grain in the diet.     

The influence of xylanase on the fermentability,digestibility, and physicochemical properties of insoluble corn-based fiber along the gastrointestinal tract of growing pigs

In theory, supplementing xylanase in corn-based swine diets should improve nutrient and energy digestibility and fiber fermentability, but its efficacy is inconsistent. The experimental objective was to investigate the impact of xylanase on energy and nutrient digestibility, digesta viscosity, and fermentation when pigs are fed a diet high in insoluble fiber (>20% neutral detergent fiber; NDF) and given a 46-d dietary adaptation period. A total of 3 replicates of 20 growing gilts were blocked by initial body weight, individually housed, and assigned to 1 of 4 dietary treatments: a low-fiber control (LF) with 7.5% NDF, a 30% corn bran high-fiber control (HF; 21.9% NDF), HF + 100 mg xylanase/kg (HF + XY [Econase XT 25P; AB Vista, Marlborough, UK]) providing 16,000 birch xylan units/kg; and HF + 50 mg arabinoxylan-oligosaccharide (AXOS) product/kg (HF + AX [XOS 35A; Shandong Longlive Biotechnology, Shandong, China]) providing AXOS with 3–7 degrees of polymerization. Gilts were allowed ad libitum access to fed for 36-d. On d 36, pigs were housed in metabolism crates for a 10-d period, limit fed, and feces were collected. On d 46, pigs were euthanized and ileal, cecal, and colonic digesta were collected. Data were analyzed as a linear mixed model with block and replication as random effects, and treatment as a fixed effect. Compared with LF, HF reduced the apparent ileal digestibility (AID), apparent cecal digestibility (ACED), apparent colonic digestibility (ACOD), and apparent total tract digestibility (ATTD) of dry matter (DM), gross energy (GE), crude protein (CP), acid detergent fiber (ADF), NDF, and hemicellulose (P < 0.01). Relative to HF, HF + XY improved the AID of GE, CP, and NDF (P < 0.05), and improved the ACED, ACOD, and ATTD of DM, GE, CP, NDF, ADF, and hemicellulose (P < 0.05). Among treatments, pigs fed HF had increased hindgut DM disappearance (P = 0.031). Relative to HF, HF + XY improved cecal disappearance of DM (162 vs. 98 g; P = 0.008) and NDF (44 vs. 13 g; P < 0.01). Pigs fed xylanase had a greater proportion of acetate in cecal digesta and butyrate in colonic digesta among treatments (P < 0.05). Compared with LF, HF increased ileal, cecal, and colonic viscosity, but HF + XY decreased ileal viscosity compared with HF (P < 0.001). In conclusion, increased insoluble corn-based fiber decreases digestibility, reduces cecal fermentation, and increases digesta viscosity, but supplementing xylanase partially mitigated that effect.     

Growth performance and carcass quality are not different between pigs fed diets containing cold-fermented low-oil DDGS and pigs fed conventional DDGS,but pelleting improves gain to feed ratio regardless of source of DDGS

The objective of this study was to test the hypothesis that growth performance and carcass characteristics of pigs fed diets containing cold-fermented, low oil distillers dried grains with solubles (DDGS) is not different from that of pigs fed diets containing conventional DDGS regardless of the physical form of the diets. A total of 160 barrows and gilts were used. There were 4 diets, 10 pens per diet, and 4 pigs per pen. Pigs were weaned at 21 d of age and fed a common phase 1 diet that did not contain DDGS during the initial 7 d post-weaning. Pigs were then allotted to the four diets that were arranged in a 2 × 2 factorial design with two sources of DDGS (cold-fermented and conventional DDGS) and two diet forms (meal and pellets). Pigs were fed phase 2 diets from day 7 to 21 and phase 3 diets from day 21 to 43 post-weaning. All diets were based on corn and soybean meal, but phase 2 diets also contained 15% DDGS and phase 3 diets contained 30% DDGS. From day 43, pigs were fed grower diets for 38 d, early finisher diets for 38 d, and late finisher diets for 18 d and these diets also contained 30% DDGS. Feed was provided on an ad libitum basis and daily feed allotments were recorded. Pigs were weighed at the beginning of each phase and at the conclusion of the experiment. On the last day of the experiment, the pig in each pen with a body weight that was closest to the pen average was slaughtered and carcass measurements were determined. Combined results for the two nursery phases indicated that feeding meal diets instead of pelleted diets increased (P < 0.001) average daily feed intake and decreased (P < 0.05) gain to feed ratio (G:F). However, no differences between the two sources of DDGS were observed for the overall growth performance of weanling pigs. For the entire growing-finishing period, the source of DDGS did not affect growth performance, but pigs fed meal diets had reduced (P < 0.001) G:F compared with pigs fed the pelleted diets. There were no differences between the two sources of DDGS for carcass characteristics. Back fat was greater (P < 0.05) for pigs fed pelleted diets than for pigs fed meal diets. In conclusion, no differences in growth performance or carcass characteristics between pigs fed cold-fermented DDGS and pigs fed conventional DDGS were observed. However, pigs fed pelleted diets had greater G:F and greater back fat than pigs fed meal diets.     

Effect of dietary crude protein level on growth performance,blood characteristics,and indicators of intestinal health in weanling pigs

An experiment was conducted to test the hypothesis that reducing crude protein (CP) in starter diets for pigs reduces post-weaning diarrhea and improves intestinal health. In total, 180 weanling pigs were allotted to 3 diets containing 22, 19, or 16% CP. Fecal scores were visually assessed every other day. Blood samples were collected from 1 pig per pen on days 1, 6, 13, 20, and 27, and 1 pig per pen was euthanized on day 12. Results indicated that reducing dietary CP reduced (P < 0.01) overall average daily gain, gain to feed ratio, final body weight, and fecal scores of pigs. Pigs fed the 16% CP diet had reduced (P < 0.01) serum albumin compared with pigs fed other diets. Blood urea nitrogen, haptoglobin, interleukin-1β, and interleukin-6 concentrations in serum were greatest (P < 0.01) on day 13, whereas tumor necrosis factor-α and interleukin-10 concentrations were greatest (P < 0.01) on day 6. Villus height in the jejunum increased (P < 0.05) and crypt depth in the ileum was reduced (P < 0.01) if the 19% CP diet was fed to pigs compared with the 22% CP diet. A reduction (P < 0.05) in mRNA abundance of interferon-γ, chemokine ligand 10, occludin, trefoil factor-2, trefoil factor-3, and mucin 2 was observed when pigs were fed diets with 16% CP. In conclusion, reducing CP in diets for weanling pigs reduces fecal score and expression of genes associated with inflammation.     

Improving performance of finishing pigs with added valine,isoleucine, and tryptophan: validating a meta-analysis model

Based on results of a recent meta-analysis, we hypothesized that increased dietary Val, Ile, or Trp could correct possible amino acid interactions because of excess Leu in diets containing high levels of corn protein, namely dried distiller’s grains with solubles (DDGS). A total of 1,200 pigs (PIC TR4 × (Fast LW × PIC L02); initially 33.6 ± 0.6 kg) were used in a 103-d study. The 6 dietary treatments were corn–soybean meal (SBM)-DDGS-based as follows: (1) high SBM and low level of l-Lys HCl (HSBM), (2) high l-Lys HCl and moderate Ile, Val, Trp (AA above NRC 2012 estimates; NC), (3) moderate l-Lys HCl and high Ile, Val, and Trp (PC), and PC with either increased (4) L-Val (PC+Val), (5) L-Ile (PC+Ile), or (6) L-Trp (PC+Trp). Pigs fed the NC diet were predicted to have the poorest average daily gain (ADG), the PC diet to be intermediate, and pigs fed the HSBM, PC+Val, PC+Ile, and PC+Trp have the same and highest predicted ADG. In the grower period (34 to 90 kg), ADG was greater (Ρ < 0.05) for the pigs fed HSBM and PC+Val diets than the NC with pigs fed other diets intermediate. Pigs fed HSBM were more (Ρ < 0.05) efficient (G:F) than the NC and PC with pigs fed other diets intermediate. In the finisher period (90 to 136 kg), ADG was greater (Ρ < 0.05) for pigs fed PC+Ile than that of the NC with pigs fed other diets intermediate. Pigs fed PC+Val had greater (Ρ < 0.05) average daily feed intake (ADFI) than the NC with pigs fed other diets intermediate. However, PC+Ile pigs were more (Ρ < 0.05) efficient than PC+Val with pigs fed other diets intermediate. Overall, ADG was greater (Ρ < 0.05) for pigs fed HSBM, PC+Val, and PC+Ile diets than the NC with pigs fed other diets intermediate. Pigs fed the PC+Val diet had greater (Ρ < 0.05) ADFI than the NC with pigs fed other diets intermediate. No differences were detected between treatments for overall G:F or other carcass characteristics. In conclusion, increasing Val or Ile in high l-Lys-HCl-DDGS-based diets improved growth performance compared with pigs fed diets containing high levels of l-Lys HCl without added Val and Ile. These results present evidence that the recently developed meta-analysis can predict the relative differences in overall ADG for pigs fed the NC, PC, PC+Val, and PC+Ile diets; however, the predicted G:F was less accurate. The data demonstrate that the negative effects of high Leu concentrations in corn-DDGS-based diets can be reversed by increasing the ratios of Val and Ile relative to Lys.     

Hybrid rye may replace up to 75% of the corn in diets for gestating and lactating sows without negatively impacting sow and piglet performance

An experiment was conducted to test the hypothesis that hybrid rye can replace a part of the corn in gestation and lactation diets without negatively affecting sow and litter performance. For each phase, a corn–soybean meal diet and three diets in which hybrid rye replaced 25%, 50%, or 75% of corn were formulated. Two hundred sows were randomly allotted by parity to the four treatments. Results indicated that diet did not affect body weight or average daily gain (ADG) of sows or number of pigs born. The number of pigs weaned, litter weaning weight, and litter ADG increased and then decreased (quadratic, P < 0.05) as hybrid rye in diets increased. Pig mortality and number of crushed pigs tended (quadratic, P < 0.10) to be reduced as hybrid rye was added to the diet. Serum cytokines did not differ among treatments on day 105 of gestation or in pigs on the day of weaning, but interleukin (IL)-4, IL-10, and IL-18 on day 13 of lactation increased and then decreased (quadratic, P < 0.05) as hybrid rye inclusion increased in diets. Milk urea N increased (linear, P < 0.05) as hybrid rye was included in the diet, but no other differences in milk composition were observed. Overall, replacing 25% or 50% of corn with hybrid rye resulted in improved lactation performance, and replacing 75% of corn with hybrid rye resulted in sow and litter performance that was not different from that of sows fed control diets.     

Effect of low doses of Aspergillus niger phytase on growth performance, bone strength, and nutrient absorption and excretion by growing and finishing swine fed corn-soybean meal diets deficient in available phosphorus and calcium

Two experiments were conducted to evaluate the efficacy of low doses of Aspergillus niger (AN) phytase for growing and finishing pigs fed corn-soybean meal (SBM) diets with narrow Ca:P ratios that were about 0.9 g/kg deficient in available P and Ca. Experiment 1 utilized 120 pigs with an early finisher period from 51.5 +/- 0.2 to 89.7 +/- 0.9 kg of BW and a late finisher period that ended at 122.5 +/- 2.0 kg of BW. During each period, treatments were the low-P diets with 0, 150, 300, or 450 units (U) of AN phytase added/kg of diet, and a positive control (PC) diet. There were linear increases (P < or = 0.001) in bone strength and ash weight, the absorption of P (g/d and %) and Ca (%), and overall ADG (P = 0.01) with increasing concentration of AN phytase. Pigs fed the diets with 150, 300, or 450 U of AN phytase/kg did not differ from pigs fed the PC diet in growth performance overall, and pigs fed the diets with 300 or 450 U of AN phytase did not differ in P and Ca absorption (g/d) or bone ash weight from pigs fed the PC diet. However, only pigs fed the diet with 450 U of AN phytase/kg had bone strength similar to that of pigs fed the PC diet. Experiment 2 utilized 120 pigs in a grower phase from 25.3 +/- 0.1 to 57.8 +/- 0.8 kg of BW and a finisher phase that ended at 107.6 +/- 1.0 kg of BW. Treatments were the low-P diet with AN phytase added at 300, 500, or 700 U/kg of grower diet, and 150, 250, or 350 U/kg of finisher diet, respectively, resulting in treatments AN300/150, AN500/250, and AN700/350. Growth performance and the absorption (g/d) of P and Ca for the grower and finisher phases were not different for pigs fed the diets containing AN phytase and pigs fed the PC diets. However, pigs fed the PC diets excreted more fecal P (g/d, P < or = 0.01) during the grower and more P and Ca (g/d, P < 0.001) during the finisher phases than the pigs fed the diets with phytase. There were linear increases (P < or = 0.05) in bone strength and bone ash weight with increasing concentration of AN phytase. However, pigs fed the PC diets had a greater bone strength and bone ash weight than pigs fed diets AN300/150, AN500/250 (P < or = 0.02), or AN700/350 (P < or = 0.08). There were no treatment responses for N or DM digestibility in either experiment. Phytase supplementation reduced fecal P excretion from 16 to 38% and fecal Ca excretion from 21 to 42% in these experiments. In conclusion, 450 U of AN phytase/kg was effective in replacing 0.9 g of the inorganic P/kg of corn-SBM diet for finishing swine based on bone strength, whereas 300 or 150 U of AN phytase/kg of diet maintained growth performance of grower or finisher pigs, respectively.     

Effects of a novel bacterial phytase expressed in Aspergillus Oryzae on digestibility of calcium and phosphorus in diets fed to weanling or growing pigs

In 2 experiments, 48 weanling (initial BW: 13.5 ± 2.4 kg, Exp. 1) and 24 growing pigs (initial BW: 36.2 ± 4.0 kg, Exp. 2) were used to determine effects of a novel bacterial 6-phytase expressed in Aspergillus oryzae on the apparent total tract digestibility (ATTD) of phosphorus and calcium in corn-soybean meal diets fed to weanling and growing pigs. In Exp. 1 and 2, pigs were randomly allotted to 6 dietary treatments using a randomized complete block design and a balanced 2 period changeover design, respectively. In both experiments, 6 diets were formulated. The positive control diet was a corn-soybean meal diet with added inorganic phosphorus (Exp. 1: 0.42 and 0.86% standardized total tract digestible phosphorus and total calcium, respectively; Exp. 2: 0.32 and 0.79% standardized total tract digestible phosphorus and total calcium, respectively). A negative control diet and 4 diets with the novel phytase (Ronozyme HiPhos, DSM Nutritional Products Inc., Parsippany, NJ) added to the negative control diet at levels of 500, 1,000, 2,000, and 4,000 phytase units (FYT)/kg were also formulated. In Exp. 1, the ATTD of phosphorus was greater (P < 0.01) for the positive control diet (60.5%) than for the negative control diet (40.5%), but increased (linear and quadratic, P < 0.01) as phytase was added to the negative control diet (40.5% vs. 61.6%, 65.1%, 68.7%, and 68.0%). The breakpoint for the ATTD of phosphorus (68.4%) was reached at a phytase inclusion level of 1,016 FYT/kg. In Exp. 2, the ATTD of phosphorus was greater (P < 0.01) for the positive control diet (59.4%) than for the negative control diet (39.8%) and increased (linear and quadratic, P < 0.01) as phytase was added to the negative control diet (39.8% vs. 58.1%, 65.4%, 69.1%, and 72.8%). The breakpoint for the ATTD of phosphorus (69.1%) was reached at a phytase inclusion level of 801 FYT/kg. In conclusion, the novel bacterial 6-phytase improved the ATTD of phosphorus and calcium in both weanling and growing pigs. The optimum level of inclusion for this phytase is 800 to 1,000 FYT/kg of complete feed to maximize ATTD of phosphorus and calcium in weanling and growing pigs.