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Twenty-four gestating sows and 24 lactating sows were randomly allotted to three diets with eight replicate sows per treatment in a 3 × 2 factorial arrangement. Different sows were used in gestation and lactation periods. The hypothesis was that digestibility of gross energy (GE), dry matter (DM), and nutrients in lactating sows is not different from that in gestating sows. A corn–soybean-meal diet and two full-fat-rice-bran or defatted rice bran diets were used. Results indicated that regardless of diet, lactating sows had greater (P

Two experiments were conducted to determine standardized ileal digestibility (SID) of amino acids (AA) and the concentration of metabolizable energy (ME) in non-heat-treated and heat-treated soybean expellers (L-0, L-12, and L-48). L-0 underwent short-term steam conditioning for 60 s, whereas L-12 and L-48 underwent short-term steam conditioning for 60 s and long-term steam conditioning for 12 or 48 min. All heat-treated soybean expellers were expander processed. In experiment 1, 10 ileal-cannulated barrows (54.22 ± 4.54 kg) were allotted to a replicated 5 × 4 Youden square design with eight replicate pigs per diet. Each source of soybean expellers was included in one diet, and a nitrogen-free diet was also used. Results indicated that the SID of AA in non-heat-treated soybean expellers was less (P

An experiment was conducted to test the hypothesis that inclusion of a conventional torula yeast or a torula yeast produced from forestry byproducts (i.e., woody torula yeast) in diets for weanling pigs instead of fish meal and plasma protein improves growth performance and intestinal health of pigs. A total of 120 weanling pigs (6.53 ± 0.78 kg) were allotted to three treatments with ten replicate pens per diet. Pigs were fed one of three diets from days 1 to 14 post-weaning (phase 1), whereas all pigs were fed a common diet in phase 2 (days 15 to 28). The three treatments in phase 1 included a control diet with 5% fish meal, 3.5% plasma protein, and no torula yeast. The second diet contained 1.5% fish meal, 14% woody torula yeast, and no plasma protein, whereas the third diet contained 1.5% fish meal, 14% conventional torula yeast, and no plasma protein. Fecal scores were assessed every other day. On day 7, one pig per pen was euthanized to collect ileal tissue and mucosa for determination of morphology and for ribonucleic acid (RNA) sequencing analysis. At the end of phases 1 and 2, blood samples were collected and concentrations of cytokines, plasma urea nitrogen (PUN), peptide YY, immunoglobulin G, total protein, and albumin were analyzed. Results indicated that both torula yeast sources could replace fish meal and plasma protein without affecting growth performance, intestinal morphology, or blood characteristics of pigs. Pigs fed a diet containing torula yeast had improved (P < 0.05) fecal scores during phase 1. Pigs fed the conventional torula yeast diet had greater (P < 0.05) concentration of interleukin-2 compared with pigs fed the control diet. On day 14, greater (P < 0.05) concentrations of interleukin-4 and interleukin-10 were observed in pigs fed the diet containing the woody torula yeast or conventional torula yeast compared with pigs fed the control diet. Results from the RNA sequencing indicated that 19 of 24 analyzed genes involved in digestion and absorption of protein and vitamins were downregulated in pigs fed the diet containing woody torula yeast compared with pigs fed the control diet. However, only two genes (i.e., ANKS4B and FAM54A) were downregulated in pigs fed the woody torula yeast diet compared with the conventional torula yeast diet. In conclusion, using woody or conventional torula yeast instead of fish meal and plasma protein in the phase 1 diet for weanling pigs may improve intestinal health without influencing growth performance of pigs.

Two experiments were conducted to test the hypothesis that corn kernel hardness and drying temperature influence the ileal digestibility of starch and amino acids (AA), as well as apparent total tract digestibility (ATTD) of gross energy (GE) and total dietary fiber (TDF) in diets for growing pigs. Two corn varieties with average or hard endosperm were grown and harvested under similar conditions, and after harvest, each variety was divided into 2 batches that were dried at 35 and 120 °C, respectively. Therefore, four batches of corn were used. In experiment 1, 10 pigs (67.00 ± 2.98 kg) with a T-cannula installed in the distal ileum were allotted to a replicated 5 × 5 Latin square design with 5 diets and 5 periods giving 10 replicates per diet. A nitrogen-free diet and four diets containing each source of corn as the only AA source were formulated. Results indicated that neither variety of corn nor drying temperature influenced apparent ileal digestibility of starch in the grain. The standardized ileal digestibility of most AA was less (P

An experiment was conducted to test the hypothesis that increasing levels of a novel phytase increases the apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients in diets fed to young pigs. A negative control (NC) diet based on corn, soybean meal, and canola meal that contained approximately 0.83% phytate (i.e., 0.23% phytate-bound P) was formulated to be deficient in Ca, P, and standardized ileal digestible amino acids (AA). Five additional diets were formulated by adding 250, 500, 1,000, 2,000, or 4,000 phytase units/kg of the novel phytase to the NC diets. Eighteen ileal-cannulated pigs (17.81 ± 1.71 kg) were allotted to a 6 × 3 incomplete Latin square design with six diets and three 11-day periods. There were three pigs per diet in each period; therefore, there were nine replicate pigs per diet. The initial 5 d of each period was considered an adaptation period to the diet. For each period, fecal samples were collected via anal stimulation on days 6, 7, 8, and 9, whereas ileal digesta were collected on days 10 and 11 using standard procedures. Results indicated that the AID of crude protein, indispensable AA, and dispensable AA was increased (quadratic, P0.05) as the concentration of microbial phytase increased in the diets. Dietary inclusion of the novel phytase at 1,000 or 2,000 FTU/kg increased the AID of total AA from 73.7% to 79.8%. Increasing levels of microbial phytase increased (quadratic, P0.05) the AID of dry matter and minerals (i.e., Ca, P, K, Mg, Cu) in the diets. Likewise, a linear increase (P0.05) in the AID of ash and Na was observed as the inclusion level of phytase increased in the diets. Increasing levels of microbial phytase increased (linear, P0.01) the AID of gross energy (GE) and starch in the diets. A quadratic (P0.05) increase in the ATTD of ash, Ca, P, K, and Cu in experimental diets was observed as the concentration of microbial phytase increased in the diets. The ATTD of Mg and GE also increased (linear; P0.05) as concentration of dietary phytase increased. In conclusion, the novel microbial phytase used in this experiment was effective in increasing the AID of dry matter, GE, starch, minerals, and AA, as well as the ATTD of gross energy and minerals in diets formulated to be deficient in Ca, P, and AA.The effect of microbial phytase on amino acid (AA) digestibility has been inconsistent, but in many experiments, relatively low levels of phytase were used and it is not known if greater concentrations of phytase are needed to increase AA digestibility. A novel consensus bacterial 6-phytase variant has been recently developed, but it is not known if this phytase results in increased digestibility of AA and other nutrients. Therefore, an experiment was conducted to test the hypothesis that dietary inclusion of increasing levels of the novel phytase (i.e., 0, 250, 500, 1,000, 2,000, and 4,000 phytase units/kg) increases ileal digestibility of AA and total tract digestibility of energy and minerals in diets for growing pigs. In this experiment, it was demonstrated that increasing levels of phytase increased the apparent ileal digestibility of starch, gross energy, minerals, crude protein, and AA, as well as the apparent total tract digestibility of gross energy and minerals. The impact of phytase on AA digestibility is possibly dependent on diet composition, phytate and phytase sources and concentrations, and pig maturity; however, further research is needed to confirm this.

An experiment was conducted to test the hypothesis that increasing levels of phytase increases apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients in diets fed to young pigs. A negative control (NC) diet that was deficient (compared with NRC recommendation) in total Ca (-0.15%), standardized total tract digestible P (-0.16%), net energy (-33 kcal/kg), and standardized ileal digestible amino acids (average -0.02% unit) was formulated. Five additional diets were formulated by adding 250, 500, 1,000, 2,000 or 4,000 phytase units per kg of a novel consensus bacterial 6-phytase variant (PhyG) to the NC diet. All diets were based on corn, soybean meal, and canola meal. Eighteen ileal-cannulated pigs (17.81 ± 1.71 kg) were allotted to a 6 × 3 incomplete Latin square design with 6 diets and 3 periods. There were 3 pigs per diet in each period; therefore, there were nine replicate pigs per diet. Data were analyzed using the Mixed Procedure of SAS with diet as the fixed effect whereas pig and period were considered random effects. Linear and quadratic effects of PhyG on nutrient digestibility were determined using polynomial contrast statements. Linear (P < 0.01) and quadratic (P < 0.05) increases in AID of all individual amino acids (except Arg) were observed as dietary concentrations of PhyG increased (Table 1). Likewise, an increase (linear, P < 0.01; quadratic, P < 0.05) in ATTD of minerals in diets was observed as the concentration of PhyG increased in diets. Increasing levels of PhyG in diets also increased (linear, P < 0.05) ATTD of gross energy. In conclusion, increasing levels of the novel phytase (PhyG) effectively increased ileal and total tract digestibility of nutrients by pigs.

An experiment was conducted to test the hypothesis that increasing levels of phytase increases mineral digestibility and growth performance of pigs fed diets with 3,000 mg/kg of Zn. A positive control (PC) diet that met nutrient requirements and a negative control (NC) diet that was deficient in total Ca (-0.16%), digestible P (-0.14%), metabolizable energy (-50 kcal/kg), and digestible amino acids (-0.02%) were formulated. Eight additional diets were formulated by adding 500, 1,000, 1,500, or 2,000 phytase units/kg of a novel bacterial 6-phytase (PhyG) or a commercial Buttiauxella phytase (PhyB) to the NC diet. A randomized complete block design with 400 weanling pigs (5.82 ± 0.70 kg), 10 diets, 4 pigs per pen, and 10 replicate pens per diet was used. Pigs were fed the experimental diets for 28 d. Fecal samples were collected from 1 pig per pen on d 26 to 28. Linear and quadratic effects of PhyG and PhyB were determined using polynomial contrast statements. Contrast statements were used to compare effects of PC diet with NC diet, and to compare effects of PhyG diets with PhyB diets. Overall, pigs fed the NC diet had reduced growth performance (P < 0.05) compared with pigs fed the NC diet (Table 1). Linear (P < 0.01) and quadratic (P < 0.05) increases in overall average daily gain and average daily feed intake of pigs were observed as dietary concentrations of PhyG or PhyB increased. Increasing levels of PhyG or PhyB linearly increased (P < 0.01) the apparent total tract digestibility (ATTD) of P and Ca. PhyG increased ATTD of P more (P < 0.05) than PhyB. In conclusion, both phytases are effective in increasing mineral digestibility and growth performance in pigs fed diets with pharmacological levels of Zn; however, PhyG improved P digestibility more than PhyB.

Two experiments were conducted to test the hypothesis that digestibility of amino acids (AA), gross energy (GE), acid hydrolyzed ether extract (AEE), and neutral detergent fiber (NDF), and values for metabolizable energy (ME) in low-oil distillers dried grains with solubles (DDGS) vary among suppliers. In Exp. 1, the apparent total tract digestibility (ATTD) of GE, AEE, and NDF, and concentration of ME were determined in eight sources of DDGS (sources A, B, C, D, E, G, H, and I). A corn-based basal diet and eight diets containing corn and each source of DDGS were fed to 72 barrows (initial body weight = 18.1 ± 1.3 kg) with eight pigs per diet. Feces and urine were collected for 5 d after 7 d of adaptation. The ME did not differ among the eight sources of DDGS with the exception that DDGS source E contained less (P < 0.05) ME than DDGS source D. The ATTD of GE did also not differ among the eight sources of DDGS, but ME and ATTD of GE in corn were greater (P < 0.05) than in the eight sources of DDGS. However, the ATTD of AEE in corn and the eight sources of DDGS was not different, but the ATTD of AEE in DDGS source E was greater (P < 0.05) than in DDGS source A. The ATTD of NDF in DDGS source D was also greater (P < 0.05) than in DDGS sources E, G, and H, but ATTD of NDF did not differ between corn and the eight sources of DDGS. In Exp. 2, standardized ileal digestibility (SID) of AA was determined in seven sources of DDGS (sources A, B, C, D, E, G, and H). Twenty-four barrows (initial body weight = 63.4 ± 3.4 kg) that had a T-cannula installed in the distal ileum were allotted to a two-period incomplete Latin square design with eight diets. Seven diets were formulated to contain each of the seven sources of DDGS and an N-free diet was also used. Ileal digesta were collected for 2 d after 5 d of adaptation. There were no differences between pigs fed DDGS sources A and B in SID of AA, and the SID of Lys, Met, and Trp did not differ among DDGS sources A, B, and E. However, SID of most indispensable and dispensable AA except Gly were greater (P < 0.05) in DDGS source B than in DDGS sources C, D, E, G, and H. In conclusion, variability in SID of AA, ATTD of NDF and AEE, and ME were observed among the sources of DDGS used in this experiment.

An N-balance experiment was conducted to test the hypothesis that d-Methionine (d-Met) has the same bioavailability and efficacy as l-Methionine (l-Met) when fed to weanling pigs. A Met-deficient basal diet containing 0.24% standardized ileal digestible (SID) Met was formulated. Six additional diets were formulated by adding 0.036%, 0.072%, or 0.108% d-Met or l-Met to the basal diet, and these diets, therefore, contained 77%, 87%, or 97% of the requirement for SID Met. Fifty-six barrows (10.53 ± 1.17 kg) were housed in metabolism crates and allotted to the seven diets with eight replicate pigs per diet. Feces and urine were collected quantitatively with 7-d adaptation and 5-d collection periods. Blood and tissue samples from pigs fed the basal diet and pigs fed diets containing 0.108% supplemental Met were collected on the last day. Results indicated that N retention (%) linearly increased (P < 0.01) as supplemental d-Met or l-Met increased in diets. Based on N retention (%) as a response, the linear slope-ratio regression estimated the bioavailability of d-Met relative to l-Met to be 101% (95% confidence interval: 57%–146%). The villus height and crypt depth in the jejunum were not affected by the Met level or Met source. Total antioxidant capacity or thiobarbituric acid reactive substance concentrations in plasma or tissue samples from pigs fed the control diet or diets containing 0.108% supplemental d-Met or l-Met were not different. Abundance of mRNA for some AA transporters analyzed in intestinal mucosa of pigs also did not differ. Therefore, it is concluded that d-Met and l-Met are equally bioavailable for weanling pigs.

An experiment was conducted to test the hypothesis that increasing levels of phytase increases mineral digestibility and bone ash by pigs fed diets containing 0.23%, 0.29%, or 0.35% phytate-P. Within each level of phytate, 5 diets were formulated based on corn, soybean meal, and canola meal to contain 0, 500, 1,000, 2,000, or 4,000 phytase units (FTU)/kg of a novel consensus bacterial 6-phytase variant (PhyG). In addition, 3 reference diets were formulated by adding a commercial Buttiauxella phytase (PhyB) at 1,000 FTU/kg to the 3 diets containing no PhyG. A randomized complete block design with 144 pigs (12.70 ± 4.01 kg), 18 diets, and 8 replicate pigs per diet was used. Pigs adapted to diets for 15 d followed by 4 d of fecal collection. Femurs were collected on the last day. Data were analyzed as a 3 × 5 factorial with 3 levels of phytate-P and 5 levels of phytase, and contrast statements were used to compare 1,000 FTU of PhyG with PhyB. Pig was the experimental unit. Diets containing 0.35% phytate-P had reduced (P < 0.01) apparent total tract digestibility (ATTD) of Ca, P, Mg, and K compared with diets containing 0.23% or 0.29% phytate-P, but inclusion of phytase increased (P < 0.01) ATTD of Ca, Na, and K (Table 1). Phytase increased ATTD of P and Mg, but to a greater extent in diets with 0.23 or 0.29% phytate-P than in diets with 0.35% phytate-P (interaction, P < 0.05). Phytase increased bone ash, but to a greater extent if there was 0.35 rather than 0.23 or 0.29% phytate-P in the diets (interaction, P < 0.05). PhyG increased ATTD of P more (P < 0.05) than PhyB. In conclusion, the novel consensus phytase is effective in increasing bone ash and ATTD of Ca, P, Na, Mg and K.

Three experiments were conducted to test the hypothesis that standardized ileal digestibility (SID) of amino acids (AA) and digestible energy (DE) and metabolizable energy (ME) in a new source of corn protein are greater than in corn distillers dried grains with solubles (DDGS) and that corn protein may be included in diets for weanling pigs. In experiment 1, the SID of AA was determined in two sources of DDGS (DDGS-1 and DDGS-2) and in corn protein. Results indicated that SID of most AA was greater (P < 0.05) in DDGS-2 and corn protein than in DDGS-1, but corn protein contained more digestible AA than both sources of DDGS. In experiment 2, the DE and ME in corn, the two sources of DDGS, and corn protein were determined. Results demonstrated that DE (dry matter basis) in corn protein was greater (P < 0.05) than in corn, but ME (dry matter basis) was not different between corn and corn protein. However, DE and ME in corn (dry matter basis) were greater (P < 0.05) than in DDGS-1 and DDGS-2. In experiment 3, 160 weanling pigs were allotted to four treatments in phases 1 and 2 and a common diet in phase 3. Corn protein was included at 5% to 10% in phases 1 and 2 at the expense of plasma protein and enzyme-treated soybean meal. Results indicated that although differences in average daily gain and gain to feed ratio were observed in phase 1, no differences among treatments were observed for the overall experimental period. In conclusion, the concentration of digestible AA is greater in corn protein than in DDGS; DE and ME in corn protein are also greater than in DDGS; and up to 10% corn protein may be included in phase 1 and phase 2 diets for 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.

An experiment was conducted to test the hypothesis that feed flavor and feed sweetener improve growth performance of weanling pigs. One hundred twenty-eight pigs (5.97 ± 0.55 kg) were allotted to 4 treatments with 4 pigs per pen and 8 pen replicates per diet. A 3-phase feeding program was used. In all phases, a control diet was formulated based on corn and soybean meal, and 3 additional diets were formulated by adding feed flavor (500 mg/kg), feed sweetener (150 mg/kg), or their combination to the control diet. Fecal scores were visually assessed using a score from 1 to 5 (1 = normal feces to 5 = watery diarrhea). Experimental diets were fed to pigs for 6 wk. Data were analyzed using SAS with pen as the experimental unit. Diet was the fixed effect and replicate was the random effect. Results indicated that overall average daily feed intake (ADFI) was greater (P < 0.05) and overall average daily gain (ADG) tended to be greater (P < 0.10) for pigs fed the diet containing feed sweetener compared with pigs fed the control diet (Table 1). The observed improvements in ADG and ADFI also resulted in greater (P < 0.05) final body weight for pigs fed the feed sweetener diet compared with pigs fed the control diet. Inclusion of feed flavor, feed sweetener, or the combination of feed flavor and sweetener in diets did not affect fecal scores of pigs, but inclusion of feed flavor resulted in reduced overall frequency of diarrhea (P = 0.05). In conclusion, supplementation of feed sweetener improved growth performance and feed flavor supplementation to diets ameliorated post-weaning diarrhea of weanling pigs from d 1 to 42.

An experiment was conducted to test the hypothesis that inclusion of an enzyme premix (xylanase and cellulase) in diets based on corn or sorghum and fed to growing pigs improves the apparent total tract digestibility (ATTD) of energy and total dietary fiber (TDF) and concentration of digestible energy (DE) and metabolizable energy (ME). Two basal diets based on corn and soybean meal or sorghum and soybean meal were formulated. Four additional diets were formulated by adding 40% distillers dried grains with solubles (DDGS) or 40% wheat middlings to each of the 2 basal diets. Each of these 6 diets were formulated either without or with an enzyme premix that contained xylanase and cellulase. A total of 144 pigs (61.7 ± 5.3 kg) were allotted to a randomized complete block design with 12 diets and 12 replicate pigs per diet. Pigs were housed individually and adapted to the diets for 12-d, then moved to metabolism crates and after 4 d, urine and feces were collected for 5 d. Data were analyzed as 2 × 2 × 3 factorial with 2 types of diets, two enzymes treatments, and three by-product inclusions. The pig was the experimental unit. The ATTD of gross energy (GE), and DE and ME improved (P < 0.01) if enzymes were added to the diets regardless of the grain source or by-product inclusion (Table 1). No effect of enzymes on ATTD of TDF was observed, ATTD of TDF was greater if DDGS rather than wheat middlings was added to the corn diet (grain source × by-product interaction, P < 0.05). In conclusion, addition of enzymes may have the potential to improve the ATTD of GE, and DE and ME in mixed diets based on corn or sorghum and both without and with inclusion of DDGS or wheat middlings. 3Enz = enzyme premix supplied by ADM Animal Nutrition, Quincy, IL, USA.

Three experiments were conducted to test the hypothesis that the standardized ileal digestibility (SID) of amino acids (AA), concentrations of digestible energy (DE) and metabolizable energy (ME), and the standardized total tract digestibility (STTD) of P in a new source of fermented soybean meal (Fermex 200) are greater than in conventional soybean meal (SBM-CV). In experiment 1, 9 barrows (initial body weight: 9.17 ± 1.03 kg) were surgically fitted with a T-cannula in the distal ileum and allotted to a triplicated 3 × 3 Latin square design. A nitrogen-free diet and 2 diets that contained cornstarch and SBM-CV or Fermex 200 as the sole source of crude protein (CP), and AA were formulated. Results indicated that there were no difference between SBM-CV and Fermex 200 for SID of CP and AA. In experiment 2, 24 growing pigs (initial body weight: 14.19 ± 1.18 kg) were housed individually in metabolism crates. Pigs were allotted to a corn-based diet or 2 diets that contained corn and SBM-CV or corn and Fermex 200. Feces and urine samples were collected using the marker-to-marker approach with 5-d adaptation and 4-d collection periods. Results indicated that the concentration of DE and ME in Fermex 200 were not different from DE and ME in SBM-CV. In experiment 3, 40 barrows (initial body weight: 11.01 ± 1.38 kg) were allotted to 1 of 4 diets with 10 replicate pigs per diet. Four diets were formulated to contain Fermex 200 or SBM-CV and either 0 or 1,000 units/kg of microbial phytase. Pigs were housed individually in metabolism crates. Fecal samples were collected as explained for experiment 2. Results indicated that the STTD of P in Fermex 200 was greater (P < 0.01) than in SBM-CV, but the addition of microbial phytase to the diets increased the ATTD and STTD of P in SBM-CV, but not in Fermex 200 (interaction; P < 0.01). In conclusion, the SID of AA and concentrations of DE and ME in Fermex 200 were not different from values determined for SBM-CV, but the STTD of P was greater in Fermex 200 than in SBM-CV if microbial phytase was not added to the diet.

Two experiments were conducted to test the hypothesis that torula yeast may replace animal and plant proteins in diets for weanling pigs without negatively impacting growth performance or blood characteristics. In exp. 1, 128 weanling pigs (6.71 ± 0.76 kg) were allotted to four treatments with four pigs per pen and eight replicate pens per diet. Pigs were fed one of four diets from day 1 to 14 post-weaning (phase 1), whereas all pigs were fed a common diet in phase 2 (day 15 to 28). The four dietary treatments included a control diet with 5% fish meal, 2.5% plasma protein, and no torula yeast. The second diet contained 5% fish meal, 4.75% torula yeast, and no plasma protein. The third diet contained 2.5% plasma protein, 6% torula yeast, and no fish meal, and the last diet contained 10.75% torula yeast, no fish meal, and no plasma protein. The inclusion of torula yeast was calculated to replace the amount of digestible Lys provided by fish meal, plasma protein, or both fish meal and plasma protein in the control diet. During the initial 14 d, fecal scores were visually assessed. At the end of phase 1, blood samples were collected and tumor necrosis factor-α (TNF-α), blood urea nitrogen (BUN), peptide YY, immunoglobulin G, total protein, and albumin were analyzed. Results indicated that torula yeast could replace fish meal and plasma protein without affecting growth performance, fecal scores, or blood characteristics of pigs. In exp. 2, 160 weanling pigs (6.11 ± 0.62 kg) were allotted to one of four diets with five pigs per pen and eight replicate pens per diet. Phase 1 diets contained 0%, 10%, 18%, or 26% torula yeast, whereas phase 2 diets contained 0%, 8%, 14%, or 20% torula yeast. Torula yeast was included in diets at the expense of animal proteins and soybean meal. On days 14 and 28, blood samples were collected and concentrations of cytokines, BUN, total protein, and albumin were analyzed. Phase 2 gain-to-feed ratio (G:F) linearly increased (P < 0.01) as the concentration of torula yeast increased in the diets. The concentration of albumin on day 14 linearly increased (P < 0.05) and the concentration of TNF-α was linearly reduced (P < 0.01) as the concentration of torula yeast increased in the diets. In conclusion, under the conditions of this research, torula yeast could replace fish meal and plasma protein without affecting the growth performance of pigs, but inclusion of increasing levels of torula yeast improved G:F of pigs, which may be because of greater nutrient utilization.

Five experiments were conducted to determine the standardized total tract digestibility (STTD) of P, digestible energy (DE), metabolizable energy (ME), and standardized ileal digestibility (SID) of amino acids (AA) in three sorghum varieties compared with corn and to determine the effects of sorghum varieties on nursery pig growth. In exp. 1, 48 barrows (initially 18.6 kg) were housed individually in metabolism crates. Treatments were arranged in a 2 × 4 factorial evaluating two levels of microbial phytase (0 or 500 units/kg) and four grain sources (corn, high-lysine, red, or white sorghum). Added phytase improved (P < 0.05) STTD of P in all ingredients, but was not different among the grains. In exp. 2, the DE and ME in the three sorghum varieties were not different from corn. In exp. 3, 10 growing barrows (initially 25.9 kg) with a T-cannula in the terminal ileum were used. Standardized ileal digestible Lys, Met, Thr, and Val were greater (P < 0.05) in corn than in the sorghum-based diets with no differences among the sorghum varieties. In exp. 4, 160 pigs (initially 6.3 kg) were randomly allotted to one of four dietary treatments with five pigs per pen and eight replicate pens per treatment in a 20-d experiment. Dietary treatments included corn or the three sorghum varieties, where the varieties of sorghum replaced corn on an SID Lys basis. No differences among treatments were observed in any growth performance parameters. In exp. 5, treatments consisted of a corn-based diet, a diet based on conventional sorghum (a mixture of red and white sorghum), and four diets with high-lysine sorghum containing increasing amounts of feed-grade AA, replacing soybean meal. Overall, pigs fed the high-lysine sorghum diet with the greatest amount of added feed-grade AA had the poorest gain:feed ratio (G:F; P < 0.05) compared with pigs fed all the other experimental diets. Within those fed the high-lysine sorghum and feed-grade AA, average daily gain, final body weight (linear, P < 0.10), and G:F (linear, P < 0.01) decreased as feed-grade AA increased. In summary, no differences in STTD of P or in DE and ME were observed among the grain sources. The SID AA values for the three sorghum varieties were not different; however, they were all lower than for corn. These results indicate that these varieties of sorghum can successfully replace corn in nursery pig diets if diets are formulated to account for differences in AA digestibility.

Two experiments were conducted to test the hypotheses that microbial phytase improves the standardized total tract digestibility (STTD) of phosphorus (P) in bakery meal and that corn may be replaced by bakery meal in diets for weanling pigs without negative effects on growth performance. Two sources of bakery meal were used in experiment 1 and one of these sources was also used in experiment 2. In experiment 1, eighty weanling barrows (initial body weight: 14.25 ± 1.91 kg) were allotted to a randomized complete block design with 10 diets and 8 replicate pigs per diet. Two basal diets based on each source of bakery meal (i.e., bakery meal 1 and bakery meal 2) were formulated without addition of microbial phytase. Eight additional diets were formulated by adding 500, 1,000, 1,500, or 3,000 units of microbial phytase to each of the 2 basal diets. Pigs were housed individually in metabolism crates and feces were collected quantitatively for 4 d after 5 d of adaptation. Results indicated that greater increases in apparent total tract digestibility and STTD of P were observed in bakery meal 1 compared with bakery meal 2 when phytase was added to diets (interaction, quadratic, P

The hypothesis that the nutritional value of corn protein (approximately 50% protein) is greater than in two sources of distillers dried grains with solubles (DDGS1 and DDGS2) was tested. In Exp. 1, eight ileal-cannulated barrows (37.1 ± 2.4 kg) were allotted to a Latin square and fed a N-free diet or diets based on corn protein, DDGS1, or DDGS2. Data were analyzed by ANOVA using SAS with treatment and replicate being fixed and random effects, respectively. Concentrations of standardized ileal digestible (SID) AA were greater (P < 0.05) in corn protein than in DDGS (Table 1). In Exp. 2, 32 barrows (16.5 ± 0.9 kg) in metabolism crates received diets based on, corn, corn protein, DDGS1, or DDGS2. Data were analyzed as in Exp. 1. Corn protein had greater (P < 0.01) ME compared with DDGS1 and DDGS2 (Table 1). In Exp. 3, 160 pigs (6.02 ± 0.84 kg) were allotted to 4 treatments with 8 pens per treatment. Phase 1 and 2 diets contained 0, 5, 5, or 10% and 0, 2.5, 7.5, or 10% corn protein, respectively, which replaced enzyme-treated soybean meal (HP300) or plasma in phase 1 or HP300 in phase 2. Diets were formulated using ME and SID AA values from Exp. 1 and 2. A common phase 3 diet was used. Data were analyzed as in Exp. 1. At the end of phase 1, BW was reduced (P < 0.05) for pigs fed the diet with the greatest inclusion of corn protein, but there was no difference at the end of the experiment (Table 2). Fecal score tended (P = 0.066) to be reduced in phase 2 for pigs fed the greatest inclusion of corn protein. In conclusion, corn protein has greater ME and digestible AA than DDGS and may reduce fecal scores of pigs

Two experiments were conducted to test the hypothesis that the coefficient of standardized ileal digestibility (CSID) of amino acids (AA), concentrations of digestible energy (DE) and metabolizable energy (ME), and the coefficient of standardized total tract digestibility (CSTTD) of phosphorus (P) in high-oil corn is greater than in conventional corn. In experiment 1, 9 pigs (81.5 ± 5.9 kg) that had a T-cannula installed in the distal ileum were allotted to a triplicated 3 × 3 Latin square design with 3 diets and 3 periods for 9 replicates per diet. A nitrogen-free diet and 2 diets that contained conventional corn or high-oil corn as the only source of crude protein (CP) and AA were formulated. Results indicated that the CSID of CP and most AA was greater (P

An experiment was conducted to test the hypothesis that Cu hydroxychloride (IntelliBond CII, Micronutrients, LLC, Indianapolis, IN) improves nutrient digestibility and alters microbial protein concentration in the gastrointestinal tract of pigs. Twenty-four barrows (33.3 ± 3.4 kg) that had a T-cannula installed in the distal ileum were allotted to a 2 × 2 factorial design with 2 levels of distillers dried grains with solubles (DDGS; 0 or 45%) and 2 levels of supplemental Cu from Cu hydroxychloride (0 or 150 mg/kg). Pigs were allotted to a 2-period switch back design with 4 diets and 6 replicate pigs per diet in each period resulting in 12 replicate pigs per diet for the 2 periods. For each period, feces were collected on d 10, 11, and 12, and ileal digesta were collected for 8 h on d 13 and 14. Data were analyzed in a 2 × 2 factorial arrangement using SAS. Fixed effects included Cu, DDGS, and the interaction between Cu and DDGS, whereas random effects included pig and period. Results indicated that inclusion of 45% DDGS to diets reduced (P < 0.05) the apparent ileal digestibility (AID) and the apparent total tract digestibility (ATTD) of dry matter, gross energy, and crude protein (Table 1), and increased (P < 0.05) the microbial protein concentration in the hindgut. The AID and ATTD of crude protein were not affected by dietary Cu concentrations, but the AID and ATTD of fat were greater (P < 0.05) in diets with Cu hydroxychloride than diets without Cu hydroxychloride. There was a reduction (P < 0.05) in microbial protein and concentration of volatile fatty acids in feces when diets were supplemented with Cu hydroxychloride. In conclusion, supplementation of Cu hydroxychloride to diets improved AID and ATTD of fat and reduced concentration of microbial protein in the hindgut.

An experiment was conducted to test the hypothesis that copper (Cu) hydroxychloride improves growth performance by upregulating the mRNA transcription of genes involved in lipid metabolism of pigs fed a diet based on corn, soybean meal (SBM), and distillers dried grains with solubles (DDGS). Thirty-two pigs (15.05 ± 0.98 kg) were allotted to 2 dietary treatments with 2 pigs per pen for a total of 8 replicate pens per treatment. Pigs were fed a corn–SBM–DDGS control diet that included Cu to meet the requirement. A second diet was formulated by adding 150 mg Cu/kg from copper hydroxychloride to the control diet. On the last day of the experiment, one pig per pen was sacrificed, and samples from liver, skeletal muscle, and subcutaneous adipose tissue were collected to analyze relative mRNA abundance of genes involved in lipid metabolism. Results indicated that overall ADG and G:F were greater (P < 0.05) for pigs fed the diet containing copper hydroxychloride compared with pigs fed the control diet. Pigs fed the diet supplemented with copper hydroxychloride also had increased (P < 0.05) abundance of cluster of differentiation 36 in the liver and increased (P < 0.05) abundance of fatty acid-binding protein 4 and lipoprotein lipase in subcutaneous adipose tissue. Inclusion of copper hydroxychloride also tended to increase (P < 0.10) the abundance of fatty acid-binding protein 1, peroxisome proliferator-activated receptor α, and carnitine palmitoyltransferase 1B in the liver, skeletal muscle, and subcutaneous adipose tissue, respectively. This indicates that dietary Cu may affect signaling pathways associated with lipid metabolism by improving the uptake, transport, and utilization of fatty acids. In conclusion, supplementation of copper hydroxychloride to the control diet improved growth performance and upregulated the abundance of some genes involved in postabsorptive metabolism of lipids.

An experiment was conducted to test the hypothesis that Cu hydroxychloride improves nutrient digestibility and alters the concentration of microbial protein in the small intestine or large intestine by pigs fed a corn-soybean meal diet or a diet based on corn, soybean meal, and distillers dried grains with solubles (DDGS). Twenty-four barrows (33.3 ± 3.4 kg) that had a T-cannula installed in the distal ileum were allotted to a 2 × 2 factorial design with 2 levels of DDGS (0% or 45%) and 2 levels of supplemental Cu from Cu hydroxychloride (0 or 150 mg/kg). A 2-period switch back design with the 4 diets and 6 replicate pigs per diet in each period was used resulting in 12 replicate pigs per diet for the 2 periods. The initial 9 d of each period was considered an adaptation period to the experimental diets. For each period, feces were collected on days 10, 11, and 12, and ileal digesta were collected for 8 h on days 13 and 14. Results indicated that inclusion of 45% DDGS to diets reduced (P < 0.05) the apparent ileal digestibility (AID) of AA and the AID and the apparent total tract digestibility (ATTD) of dry matter, gross energy, and crude protein. In contrast, inclusion of DDGS to diets increased (P < 0.05) the AID and the ATTD of acid hydrolyzed ether extract and the concentration of microbial protein in the hindgut (P < 0.05). However, the total concentration of volatile fatty acids (VFA) in ileal digesta and in feces from pigs fed the DDGS diets were not different from concentrations in pigs fed diets without DDGS. The AID and ATTD of dry matter, gross energy, and crude protein were not affected by dietary Cu concentrations, but the AID and ATTD of acid hydrolyzed ether extract were greater (P < 0.05) in diets supplemented with Cu hydroxychloride compared with diets without Cu hydroxychloride. There was also a reduction (P < 0.05) in the concentration of microbial protein and a tendency for a reduction (P < 0.10) in the total concentration of VFA in feces when diets were supplemented with Cu hydroxychloride. In conclusion, supplementation of Cu hydroxychloride to diets improved AID and ATTD of acid hydrolyzed ether extract and reduced the concentration of microbial protein in the large intestine and this effect was observed in diets containing DDGS as well as in diets without DDGS.

Two experiments were conducted to test the hypothesis that Cu hydroxychloride (IntelliBond C, Micronutrients, LLC, Indianapolis, IN) improves gain:feed of pigs by increasing apparent total tract digestibility (ATTD) of fat. In experiment 1, 144 pigs (15.40 ± 2.39 kg) were allotted to 1 of 6 treatments. Four diets contained 0, 2, 4, or 6% choice white grease (CWG) and 2 diets contained 150 mg/kg Cu from Cu hydroxychloride and 0 or 2% CWG. Data for growth performance were analyzed by contrast statements, and Cu equivalency of CWG was determined using prediction equations derived from regression procedures using SAS. Results indicated that gain:feed linearly increased (P ≤ 0.05) as CWG concentration increased in diets (Table 1). Supplementation of Cu hydroxychloride to diets improved (P ≤ 0.05) gain:feed of pigs, which resulted in a CWG equivalence of 2.8 to 3.8% for 150 mg/kg Cu hydroxychloride. In experiment 2, 80 pigs (18.24 ± 1.81 kg) were housed individually in metabolism crates and randomly allotted to 1 of 10 diets. Eight diets contained 0, 15, 30, or 45% distillers dried grains with solubles (DDGS) and 0 or 150 mg/kg Cu hydroxychloride. Two additional diets contained 2% CWG and 15% DDGS and 0 or 150 mg/kg Cu hydroxychloride. Feces were collected for 4 d after 5 d adaptation. Data were analyzed by contrast statements and regression procedures using SAS. Supplementation of Cu to diets improved (P ≤ 0.05) ATTD of fat by 20% due to reduced (P ≤ 0.05) endogenous loss of fat (from 11.23 to 7.14 g/kg dry matter intake), but did not affect energy digestibility or true total tract digestibility of fat. In conclusion, supplementation of 150 mg/kg Cu hydroxychloride to diets improved gain:feed of pigs with a CWG equivalence of 2.8 to 3.8%, but this was not due to improved energy digestibility.

Two experiments were conducted to test the hypothesis that the standardized total tract digestibility (STTD) of P and digestible energy (DE) and metabolizable energy (ME) in a new variety of high-lysine sorghum is not different from values obtained in conventional sorghum varieties or in corn. In experiment 1, 48 barrows (18.63 ± 0.89 kg) were housed individually in metabolism crates and randomly allotted to 1 of 8 diets. Diets were based on high-lysine sorghum, red sorghum, white sorghum, or corn as the sole source of P and these diets either contained no microbial phytase or 500 units/kg of phytase. Feces were collected using the marker to marker approach with 5-d adaptation and 4-d collection periods. Data were analyzed by ANOVA using the Mixed Procedure of SAS. Results indicated that phytase supplementation improved (P ≤ 0.05) STTD of P in all ingredients, but the STTD of P in high-lysine sorghum was not different from the STTD of P in other grains (Table 1). In experiment 2, 32 barrows (18.54 ± 0.77 kg) were housed individually in metabolism crates and randomly allotted to 1 of 4 diets. Diets contained high-lysine sorghum, red sorghum, white sorghum, or corn as the only energy-containing ingredient. Feces and urine samples were collected using the marker to marker approach with 5-d adaptation and 4-d collection periods. Data were analyzed as explained for Exp. 1. The ATTD of gross energy in high-lysine sorghum was less (P ≤ 0.05) than in corn, but the DE and ME in high-lysine sorghum was not different from corn. In conclusion, supplementation of phytase improved STTD of P in cereal grains, and values for STTD of P, as well as for DE and ME in high-lysine sorghum, were not different from corn, which indicates that high-lysine sorghum can replace corn in swine diets.

An experiment was conducted to test the hypothesis that the standardized ileal digestibility of crude protein (CP) and amino acids (AA) in threonine biomass (Thr-BM) and 2 sources of tryptophan biomass (Trp-BM1 and Trp-BM2) were greater than in soybean meal (SBM). Twelve weanling barrows (11.08 ± 1.06 kg) that had a T-cannula installed in the distal ileum were allotted to a replicated 6 × 6 Latin square design with 6 diets and 6 periods. A nitrogen-free diet, a diet based on SBM, and a diet based on a combination of SBM and Thr-BM were formulated. Two additional diets were formulated based on a combination of SBM and the 2 sources of tryptophan biomass. The last diet was not related to this work. Diets were fed to pigs for 7 days, and ileal digesta were collected on days 6 and 7 of each period. Results indicated that concentrations of CP and AA were greater in biomass products than in SBM, and the AID of threonine was greater (P

Two experiments were conducted to test the hypothesis that copper (Cu) from Cu hydroxychloride improves gain to feed ratio (G:F) when fed to pigs by increasing apparent total tract digestibility (ATTD) of fat. In experiment 1, 144 pigs (15.40 ± 2.39 kg) were allotted to 6 treatments with 2 pigs per pen and 12 replicate pens per diet. Pigs were fed diets with increasing concentrations of extracted fat by adding 20, 40, or 60 g/kg choice white grease (CWG) to a diet based on corn, soybean meal (SBM), and distillers dried grains with solubles (DDGS), which contained no CWG. Two additional diets were formulated by adding 150 mg/kg of Cu from Cu hydroxychloride to the diet without added CWG and to the diet with 20 g/kg added CWG. Diets were fed for 4 weeks. Results indicated that supplementation of diets with either CWG or Cu hydroxychloride improved (P

Particle size reduction, pelleting, and extrusion are feed processing technologies used to improve nutrient digestibility and achieve maximum pig growth performance. Particle size reduction may improve the digestibility of energy and nutrients. Digestibility of gross energy may be improved when the particle size is reduced in lupins, corn, soybean meal (SBM), field peas, barley, wheat, and sorghum. Reducing particle size in corn, sorghum, and wheat may also improve growth performance due to increased digestibility of nutrients. Particle size reduction may also reduce the production of short-chain fatty acids and improve dressing percentage. It has, however, been demonstrated that particle size reduction may result in development of ulcers and gastric keratinization. Pelleting is a hydrothermal technique that may improve palatability, reduce feed wastage, and modify structures of starch. Pelleting may improve the digestibility of gross energy in diets containing corn, distillers dried grains with solubles (DDGS), sorghum, barley, wheat, and SBM. Digestibility of amino acids and pig growth performance may also be increased in diets containing corn, SBM, and DDGS. Extrusion may improve the digestibility of nutrients from diets containing peas, SBM, barley, corn, DDGS, sorghum, wheat, wheat bran, and potato starch. Growth performance was improved in weanling and growing-finishing pigs upon extrusion of diets containing chickpeas, wheat, or barley. However, extrusion of ingredients resulted in inconsistent effects on growth performance. Thus, more research is needed to address the impact of feed processing technologies on different diets. Optimum temperature and pressure for pelleting and extrusion of feed ingredients must also be addressed to maximize the beneficial effect of thermal treatments.

An experiment was conducted to test the hypothesis that concentrations of digestible energy (DE) and metabolizable energy (ME) in threonine and valine biomass products are not different from those in fish meal. Two threonine biomass products (i.e., Thr-BM1 and Thr-BM2) and 1 valine biomass product (Val-BM) were obtained from the production of crystalline l -threonine and l -valine. The biomass products consist of the fermentation biomass that is left after the crystalline amino acids have been harvested at the end of fermentation. Forty weanling barrows (11.25 ± 0.65 kg) were placed individually in metabolism crates and allotted to a completely randomized design with 5 diets and 8 replicate pigs per diet. A bakery meal-based diet consisting of 973.5 g/kg bakery meal was formulated. Four additional diets containing a mixture of bakery meal and Thr-BM1, Thr-BM2, Val-BM, or fish meal were also formulated. Feces and urine samples were collected for 5 days after a 5-day adaptation period. Results indicated that the apparent total tract digestibility of gross energy was less (P

A number of feed additives are marketed to assist in boosting the pigs' immune system, regulate gut microbiota, and reduce negative impacts of weaning and other environmental challenges. The most commonly used feed additives include acidifiers, zinc and copper, prebiotics, direct-fed microbials, yeast products, nucleotides, and plant extracts. Inclusion of pharmacological levels of zinc and copper, certain acidifiers, and several plant extracts have been reported to result in improved pig performance or improved immune function of pigs. It is also possible that use of prebiotics, direct-fed microbials, yeast, and nucleotides may have positive impacts on pig performance, but results have been less consistent and there is a need for more research in this area. Keywords: Acidifiers, Direct-fed microbials, Minerals, Plant extracts, Prebiotics, Pigs

Two experiments were conducted to determine the standardized ileal digestibility (SID) of CP and AA, apparent total tract digestibility (ATTD) of GE, and DE and ME in conventional distillers dried grains with solubles (DDGS-CV) and in a novel source of high-protein distillers dried grains with solubles (DDGS-HP) produced by Lincolnway Energy (Nevada, IA). In Exp. 1, 18 barrows (initial BW: 72.47 ± 9.16 kg) that had a T-cannula installed in the distal ileum were allotted to a completely randomized design with 3 diets and 6 replicate pigs per diet. A nitrogen-free diet and 2 diets that contained cornstarch and DDGS-CV or DDGS-HP(Lincolnway) as the sole source of CP and AA were formulated. Diets were fed to pigs for 7 d, and ileal digesta were collected on days 6 and 7 of each period. The SID for Leu, Lys, Met, Phe, and Glu was greater (P < 0.05) in DDGS-HP(Lincolnway) than in DDGS-CV, and the SID of Ile, Val, and total indispensable AA, as well as the SID of Tyr, tended to be greater (P < 0.10) in DDGS-HP(Lincolnway) than in DDGS-CV. No difference between DDGS-CV and DDGS-HP(Lincolnway) was observed for the SID of CP and all other AA. In Exp. 2, 24 barrows (initial BW: 52.80 ± 2.55 kg) were housed individually in metabolism crates and randomly allotted to 1 of 3 diets. A corn-based basal diet (97.25% corn) and 2 diets that contained corn and DDGS-CV or corn and DDGS-HP(Lincolnway) were formulated. Each diet was fed to 8 pigs. Feces and urine were collected using the marker to marker approach with 7-d adaptation and 5-d collection periods. The DE and ME in DDGS-CV and DDGS-HP(Lincolnway) were calculated using the difference procedure. The DE and ME in DDGS-HP(Lincolnway) on an as-fed basis were greater (P < 0.05) than in corn and DDGS-CV, but the ATTD of GE in DDGS-HP(Lincolnway) and DDGS-CV was less (P < 0.01) than in corn. In conclusion, the SID of some AA and the DE and ME in DDGS-HP(Lincolnway) were greater than in DDGS-CV.

An experiment was conducted to test the hypothesis that copper (Cu) hydroxychloride improves growth performance and blood characteristics, and reduces diarrhea incidence in weanling pigs without or with exposure to heat stress. One hundred sixty pigs (6.14 ± 0.90 kg) were allotted to a 2 × 2 factorial arrangement with 2 levels of choice white grease (CWG; 0 or 50 g/kg) and 2 levels of Cu from Cu hydroxychloride (0 or 100 mg/kg). There were 5 pigs per pen and 8 pen replicates per diet. Fecal scores were visually assessed using a score from 1 to 5 (1 = normal feces to 5 = watery feces). On day 40 until the end of the experiment, ambient temperature was increased from 24 °C to 32 °C to create a mild heat stress. On day 14, day 28, day 40, and on day 44, blood samples were collected from 1 pig per pen and tumor necrosis factor-α (TNF-α), peptide YY, immunoglobulin G, blood urea nitrogen, total protein, and albumin were analyzed. Results indicated that there were no interactions between CWG and Cu hydroxychloride for overall growth performance. Greater (P

Two experiments determined the SID of AA in a high-lysine sorghum cultivar, followed by a growth trial to determine its effects on pig performance using increasing feed-grade AA at the expense of soybean meal. In Exp. 1, ten barrows (initially 25.9 kg) were surgically fitted with a T-cannula at the terminal ileum and randomly assigned to 1 of 5 diets in a 5-period, cross-over design. Experimental diets included a corn-based diet, a diet containing high-lysine sorghum, or two diets with either white or red sorghum cultivars. The fifth experimental diet was N-free to determine endogenous AA loss. In corn, SID CP, lysine, methionine, threonine, and valine were greater (P < 0.020) than sorghum-based diets, with no evidence for differences among the sorghum cultivars. In Exp. 2, a total of 293 pigs (initially 9.6 kg) were used. Dietary treatments were randomly assigned 20 d after weaning and consisted of a corn-based diet, a diet based on conventional sorghum, and 4 diets with high-lysine sorghum with 10 replications/treatment. The corn-based, conventional sorghum, and the first high-lysine sorghum (low) diets each contained the same amount of soybean meal with varying amounts of feed-grade AA. The 3 remaining high-lysine sorghum diets included incrementally increasing amounts of feed-grade AA (low-medium, medium-high, and high), replacing soybean meal. Overall, there was no evidence for differences in ADG or ADFI between treatments. However, pigs fed the high-lysine sorghum with the greatest amount of feed-grade AA had decreased G:F (P = 0.045) compared with those fed other experimental diets. In summary, SID AA values for the high-lysine sorghum in this study were not different from sorghum cultivars; however, these values were all lower when compared with corn. When nursery diets were formulated on an equal SID AA basis, there were no differences in ADG among pigs fed any of the diets.

Three experiments were conducted to determine effects of Cu hydroxychloride on DE and ME, apparent total tract digestibility (ATTD) of energy and acid hydrolyzed ether extract (AEE), and growth performance of pigs fed a diet based on corn and soybean meal (SBM). In Exp. 1, 80 weanling pigs (6.80 ± 1.69 kg) were allotted to 2 treatments with 4 pigs per pen and 10 pen replicates per diet. Pigs were fed a corn-SBM control diet that had Cu added to meet the requirement. A second diet was formulated by adding 150 mg Cu/kg from Cu hydroxychloride to the control diet. Both diets were fed for 4 wk. Results indicated that ADG, G:F, and final BW were greater (P ≤ 0.05) and fecal scores were reduced (P ≤ 0.05) for pigs fed the diet containing150 mg Cu/kg as hydroxychloride compared with pigs fed the control diet. In Exp. 2, 36 barrows (9.89 ± 1.21 kg) were randomly allotted to 3 dietary treatments and placed in metabolism crates. The control diet was based on corn and SBM and contained 20 mg Cu/kg. Two additional diets were formulated by adding 100 or 200 mg Cu/kg from Cu hydroxychloride to the control diet. Diets were fed for 28 d, with feces and urine being collected from d 9 to 14, d 16 to 21, and d 23 to 28. The DE and ME of diets and the ATTD of GE and AEE were not affected by dietary Cu concentrations, but increased (P < 0.01) by collection period. In Exp. 3, 150 pigs (10.22 ± 1.25 kg) were fed the same 3 diets as used in Exp. 2. Diets were provided on an ad libitum basis for 4 wk. Fecal scores were recorded, and on the last day of the experiment, blood samples were collected and tumor necrosis factor-α (TNF-α), IgA, blood urea N, total protein, and albumin were measured. Phase 1 ADG and G:F and final BW on d 28 were greater (P ≤ 0.05) for pigs fed diets containing 100 or 200 mg Cu/kg supplemented by Cu hydroxychloride compared with pigs fed the control diet. Pigs fed the diets supplemented with Cu hydroxychloride also had reduced (P ≤ 0.05) overall fecal scores and diarrhea frequency compared with pigs fed the control diet. However, no differences among treatments were observed for concentrations of TNF-α, IgA, blood urea N, total protein, or albumin. In conclusion, supplementation of Cu as Cu hydroxychloride to diets fed to weanling pigs improved growth performance and reduced diarrhea frequency, but this did not appear to be a result of increased digestibility of energy or AEE.