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Objective: Information about the chemical composition of cassava-based feed ingredients is needed to accurately formulate animal diets. A study was conducted to determine the chemical composition of cassava-based feed ingredients and to test the hypothesis that there is variation in chemical composition among cassava products originating from different South-East Asian countries.Methods: Sources of dried peeled and unpeeled cassava roots, cassava chips, cassava meal, high-ash cassava meal, and cassava residue were used. All samples were analyzed for dry matter, gross energy, nitrogen, amino acids (AA), acid-hydrolyzed ether extract (AEE), ash, minerals, total starch, insoluble dietary fiber, and soluble dietary fiber. Samples of peeled and unpeeled cassava roots, cassava chips, and cassava meal were also analyzed for sugars.Results: High-ash cassava meal had greater (p

Objective: Oilseeds and nut co-products can be used as alternative feed ingredients in animal diets because they may have a lower cost than traditional ingredients. A study was, therefore, conducted to determine the chemical composition of copra, palm kernel, and nut coproducts from South-East Asia or Australia. The hypothesis that country of production influences nutritional composition was tested.Methods: Oilseed meals included 2 copra expellers, 3 copra meals, and 12 palm kernel expellers. One source of almond hulls and cashew nut meal were also used. Samples were obtained from suppliers located in South-East Asia or Australia. All samples were analyzed for dry matter, gross energy, nitrogen, amino acids (AA), acid-hydrolyzed ether extract (AEE), ash, minerals, insoluble dietary fiber, and soluble dietary fiber. Copra and nut coproducts were also analyzed for total starch and sugars.Results: Copra expellers had greater (p

Phosphorus (P) is a macro mineral needed for bone mineralization and cell membrane structure and P is also involved in several fundamental pathways of metabolism in the body. Because of the low concentration and digestibility of P in plant ingredients that are the main components of diets for poultry and pigs, feed phosphates are usually included in diets in addition to the P contributed by plant ingredients. The most widely used feed phosphates in poultry and swine diets are dicalcium phosphate (DCP) and monocalcium phosphate (MCP), but tricalcium phosphate (TCP), monosodium phosphate (MSP), and magnesium phosphate (MgP) may be used as well. Because feed phosphates are mostly produced from rock phosphate, feed phosphates have impurities that contain minerals other than P. Concentrations of P in feed phosphates range from 14.8% (MgP) to 25.7% (MSP). The standardized total tract digestibility (STTD) of P in pigs ranges from 71% (TCP) to 95% (MSP). The STTD of Ca and the standardized ileal digestibility (SID) of P and Ca in feed phosphates fed to pigs and poultry have been determined only in a few experiments. Available data indicate that the STTD of Ca and SID of P in MCP are greater than in DCP in both poultry and pigs, but the SID of Ca is similar between DCP and MCP fed to broilers. Information on mineral concentrations and digestibility values in feed phosphates is needed in diet formulation for pigs and poultry, but if diets are formulated to contain equal concentrations of digestible P and Ca, it is unlikely that animal performance will be impacted by the source of feed phosphates used in the diet.

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.

An experiment was conducted to test the hypothesis that there are no differences among samples of sunflower coproducts in apparent total tract digestibility (ATTD) of gross energy (GE), crude protein (CP), and acid hydrolyzed ether extract (AEE), total dietary fiber (TDF), insoluble dietary fiber, soluble dietary fiber (SDF), or in metabolizable energy (ME) regardless of where the ingredient was produced. Six samples of sunflower meal (SFM) were obtained from the United States (two samples), Ukraine (two samples), Hungary, and Italy. A sample of sunflower expellers (SFE) from the United States was also used. A corn-based control diet and 7 diets containing corn and each sample of sunflower coproducts were formulated. Sixty-four barrows (initial weight = 31.5 ± 3.2 kg) were allotted to 8 diets using a randomized complete block design with four blocks of pigs from four different weaning groups. Pigs were housed individually in metabolism crates and feed was provided at three times energy requirement for maintenance. Feces and urine were collected for four days after seven days of adaptation to diets. Results indicated that the ATTD of GE and CP in SFE was less (P

Spray dried plasma (SDP) is commonly used in phase 1 diets for weanling pigs, but it is unknown if SDP affects energy or nutrient digestibility of the subsequent diet. Therefore, two experiments were conducted to test the null-hypothesis that inclusion of SDP in a phase 1 diet fed to weanling pigs will not affect energy or nutrient digestibility of a phase 2 diet without SDP. In experiment 1, 16 newly weaned barrows with an initial body weight (BW) of 4.47 ± 0.35 kg were randomly allotted to a phase 1 diet without SDP or a diet including 6% SDP for 14 d. Both diets were fed on an ad libitum basis. All pigs (BW: 6.92 ± 0.42 kg) had a T-cannula surgically inserted in the distal ileum, moved to individual pens, and fed the common phase 2 diet for 10 d with ileal digesta collection on days 9 and 10. In experiments 2, 24 newly weaned barrows (initial BW: 6.60 ± 0.22 kg) were randomly allotted to phase 1 diets without SDP or a diet containing 6% SDP for 20 d. Both diets were provided on an ad libitum basis. All pigs (BW: 9.37 ± 1.40 kg) were then moved to individual metabolism crates and fed the common phase 2 diet for 14 d with the initial 5 d being the adaptation period to the diet followed by 7 d of fecal and urine collection according to the marker-to-marker procedure. The apparent ileal digestibility (AID) of starch, crude protein (CP), amino acids (AA), and acid hydrolyzed ether extract (AEE), was determined in experiment 1, and the apparent total tract digestibility (ATTD) of gross energy (GE), insoluble-, soluble-, and total-dietary fiber, Ca, and P, and the retention and biological value of N were determined in experiment 2. The statistical model included diet as fixed effect and block and pig within block as random effects. Results of experiment 1 indicated that the AID of starch, CP, AEE, and AA in phase 2 were not affected by phase 1 treatment. Results of experiment 2 indicated that the ATTD of GE, insoluble-, soluble-, and total-dietary fiber, Ca, and P and N retention and biological value in phase 2 were also not affected by phase 1 treatment. In conclusion, feeding weanling pigs a diet with 6% SDP in phase 1 did not affect the AID or ATTD of energy and nutrients in a phase 2 diet without SDP.

Three experiments were conducted to test the hypothesis that values for standardized ileal digestibility (SID) of amino acids (AA) and metabolizable energy (ME) in a the cheese coproduct are greater than in fish meal or enzyme-treated soybean meal (ESBM). The second objective was to test the hypothesis that pigs fed a diet containing cheese coproduct will have growth performance that is not different from that of pigs fed other sources of protein. In experiment 1, eight ileal-cannulated barrows (11.0 ± 0.4 kg) were allotted to a replicated 4 × 4 Latin square design with four diets and four periods and two pigs per diet in each period. The four diets included an N-free diet and three diets that contained ESBM, fish meal, or the cheese coproduct as the source of AA. Results indicated that the cheese coproduct had greater (P < 0.05) SID of most AA compared with ESBM and fish meal. In experiment 2, 32 weanling barrows (14.0 ± 1.1 kg) were housed individually in metabolism crates and randomly allotted to one of four diets. A corn-based diet and three diets that contained corn and ESBM, fish meal, or cheese coproduct were formulated. Feces and urine were collected quantitatively. The ME in cheese coproduct was greater (P < 0.05) than in ESBM and fish meal. In experiment 3, 128 weaned pigs (6.2 ± 0.6 kg) were allotted to a randomized complete block design with four treatments and 8 replicate pens per diet. Phase 1 diets that contained 0%, 6.65%, 7.35%, or 14% cheese coproduct were fed from days 1 to 14 and a common phase 2 diet without cheese coproduct was fed from days 15 to 28. Individual pig weights were recorded at the beginning of the experiment, on days 14 and 28, and daily feed allotments were also recorded. Two blood samples were collected from 1 pig per pen on day 14 to analyze for blood urea N, albumin, total plasma protein, peptide YY, immunoglobulin G, tumor necrosis factor-α, interleukin-6, and interleukin-10. No differences were observed in average daily gain among treatments, but there was a tendency (P < 0.10) for total protein on day 14 to increase as cheese coproduct increased in the diets. In conclusion, the cheese coproduct used in this experiment has a greater SID of AA and greater ME than ESBM and fish meal and the cheese coproduct may be included in prestarter diets for weanling pigs without negatively impacting growth performance or indicators of intestinal health.

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 the apparent total tract digestibility (ATTD) and the standardized total tract digestibility (STTD) of P in feed phosphates are increased by microbial phytase when fed to growing pigs. Monocalcium phosphate (MCP), monosodium phosphate (MSP), and magnesium phosphate (MgP) from volcanic deposits were used in the experiment. Three corn-soybean meal based diets that contained 0, 500, or 4,000 units of microbial phytase (FTU), but no feed phosphates, were formulated. Nine additional diets were formulated by adding each of the three feed phosphates to the three basal diets. A P-free diet was also formulated to estimate the basal endogenous loss of P, and therefore, 13 diets were used in the experiment. A total of 117 growing barrows (initial body weight: 15.56 ± 1.68 kg) were allotted to the 13 diets with 9 pigs per diet. Pigs were housed individually in metabolism crates equipped with a feeder and a nipple drinker. Installation of a screen floor under the slatted floor allowed for collection of feces. Diets were fed for 10 d, with the initial 5 d being a period of adaptation to the diet followed by a collection period of 4 d. During the experiment, pigs were fed equal amounts of feed twice daily at 0800 and 1600 h. Results indicated that the ATTD and STTD of P in all diets increased with the inclusion of 500 or 4,000 FTU, but the ATTD and STTD of P in the feed phosphates were not affected by the inclusion of phytase. This indicates that the increases in ATTD and STTD of P that were observed in the mixed diets when phytase was used were due to the release of P from phytate in corn and soybean meal and not from an increase in digestibility of P in feed phosphates. However, MgP had a lower (P 0.05) ATTD and STTD of P than MCP and MSP. In conclusion, microbial phytase does not increase the digestibility of P in MCP, MSP, or MGP, but the digestibility of P in MgP is less than in MCP and MSP.Microbial phytase increases the digestibility by pigs of phytate-bound P in feed ingredients of plant origin, but digestible P can also be increased in diets by the addition of feed phosphates due to their high digestibility of P and lack of phytate. However, it is possible that the phytate from plant ingredients complexes with P from feed phosphates, resulting in a lower digestibility of P, but research to address this possibility has not been reported. Therefore, the hypothesis was that phytase can increase the digestibility of P in feed phosphates fed to pigs. Monocalcium phosphate (MCP), monosodium phosphate (MSP), and magnesium phosphate (MgP) were the three feed phosphates used in the experiment and the three ingredients were included in corn-soybean meal based diets. Results indicated that the inclusion of phytase increased the digestibility of P in the diets, but there was no indication that phytase affected the digestibility of P from any of the three feed phosphates, which indicates that the increase in digestibility of P likely was due to the release of P from plant ingredients in the diets. However, the digestibility of P was lower in MgP compared with MCP and MSP.

The aims of this experiment were (1) to compare the effects of a soybean meal with an enzymatic treatment (ESBM) to reduce the concentration of antinutritional factors versus a standard soybean meal (SBM) on foregut and small intestine digestion in weaned dairy calves and (2) to estimate the endogenous losses of crude protein (CP) in the small intestine. Our hypothesis was that a diet containing ESBM instead of SBM would improve ruminal and small intestine digestion and absorption of nutrients. A T-cannula was placed in the duodenum, and a second T-cannula was installed in the distal ileum of 12 Holstein calves at approximately 3 wk of age. Calves were weaned on d 42, and on d 50 they were assigned randomly to a quadruplicated 3 × 3 Latin square with 10-d periods. Digesta samples were collected on d 7 and 8 from the ileum and d 9 and 10 from the duodenum. The diets were fed for ad libitum intake and consisted of a calf starter (CS) of 20% CP with SBM as the main source of protein (CTRL), and an isonitrogenous CS with an ESBM instead of SBM (ENZT). A third diet with a low content of CP (10%) and no soy protein was fed to estimate endogenous N losses and digestibilities of test ingredients. Flows and digestibilities of nutrients were compared between CTRL and ENZT and their test ingredients (SBM vs. ESBM, respectively). Duodenal net flows of CP and total AA as well as ruminal microbial protein synthesis per kilogram of digested CP were greater, and flow of nonprotein N and CP true (corrected by endogenous and microbial flows) foregut digestibility were lower with ENZT than CTRL. The apparent small intestine digestibilities of CP and total AA were greater for ESBM than SBM, but there were no differences between the CTRL and ENZT diets. We observed no differences in digestibilities at the duodenum or ileum of starch or NDF, but true small intestine digestibilities of CP and all AA were greater with ENZT than CTRL. Total endogenous protein losses in the small intestine estimated from calves fed the low-CP with no soy protein diet were 37 ± 1.5 g of CP and 29 ± 1.4 g of AA/kg of DMI. These values may be considered the basal endogenous losses as they are similar to values obtained with the regression method, which estimates N losses when dietary N is null. Our results indicated that the inclusion of an ESBM improved the efficiency of ruminal microbial protein synthesis per digested kilogram of organic matter and CP, and increased CP and AA absorption in the small intestine despite a greater proportion of undigested dietary protein entering the duodenum.

The objective of this experiment was to test the hypothesis that increasing dietary phytase reduces basal endogenous loss of Ca and increases P balance in pigs. Seventy barrows (initial body weight: 17.66 ± 1.69 kg) were allotted to seven Ca-free diets using a randomized complete block design with two blocks and five pigs per diet in each block. All diets were based on corn, potato protein concentrate, and full-fat rice bran. A positive control (PC) diet was formulated to contain P at the requirement for standardized total tract digestible (STTD) P by 11 to 25 kg pigs. Six negative control (NC) diets were formulated by reducing the provision of digestible P by 0.15% and adding 0, 250, 500, 1,000, 2,000, or 4,000 phytase units/kg diet. Pigs were housed individually in metabolism crates that allowed for total, but separate, collection of urine and feces. Daily feed allowance was 3.0 times the maintenance requirement for metabolizable energy and was divided into two equal meals. Diets were fed for 12 d with the first 5 d considered the adaptation period. Urine collections started on day 6 in the morning and ceased on day 10 in the morning. Fecal markers were also included in the morning meals on day 6 and day 10 and feces were collected according to the marker-to-marker procedure. Results indicated that the apparent total tract digestibility of dry matter was not affected by dietary P or phytase levels. The basal endogenous loss of Ca was not affected by dietary P, but exponentially decreased (P = 0.030) as phytase level increased in the diets. Phosphorus retention (g/d) and standardized total tract digestibility of phosphorus were greater (P0.05) in pigs fed the PC diet compared with pigs fed the NC diet with no phytase. The STTD of P exponentially (P0.001) increased as phytase level increased in the diets, but because of the lack of Ca, retention of P (% of absorbed) linearly decreased (P = 0.006) as phytase increased. In conclusion, basal endogenous loss of Ca decreased as dietary phytase increased demonstrating that endogenous Ca can be bound to phytate in the intestinal tract of pigs. However, STTD of P increased as phytase level in the diets increased.Phytate in plant-based ingredients limits the amount of phosphorus available for absorption and can form indigestible complexes with endogenous calcium. However, breakdown of the phytate molecule by phytase increases digestibility of phosphorus and may also reduce endogenous loss of calcium. Therefore, the objective of this experiment was to test the hypothesis that level of phytase influences the utilization of phosphorus and basal endogenous loss of calcium in growing pigs fed calcium-free diets. Results demonstrated that total tract digestibility of phosphorus increased as phytase increased in the diets, but not all of the absorbed P was retained in the pigs due to a lack of calcium. Dietary concentration of phosphorus did not affect basal endogenous loss of calcium, but increasing concentrations of microbial phytase reduced basal endogenous loss of calcium. These results demonstrate that some endogenous calcium is bound to phytate, but including microbial phytase in diets helps release this calcium and therefore reduce endogenous loss of calcium.

An experiment was conducted to test the hypothesis that regardless of pig body weight (BW), increasing dietary phytase results in increased phytate degradation and improved digestibility of minerals, amino acids (AA), and gross energy (GE). Eighteen pigs were equipped with a T-cannula in the distal ileum and allotted to a triplicated 6 × 3 Youden square design with six diets and three collection periods of 7 d, for a total of nine replicate pigs per diet. This design was repeated four times to simulate four production phases, and there was a 7-d resting period before each collection phase started (BW at start of collections: 29.3, 53.6, 85.1, and 114.4 kg for phases 1, 2, 3, and 4, respectively). Six corn-soybean meal diets were formulated by including 0, 250, 500, 1,000, 2,000, or 4,000 phytase units/kg feed (FTU). The six diets were used throughout the experiment. Samples of feces and ileal digesta were collected in each period. Results indicated that regardless of pig BW, increasing inclusion of phytase increased (quadratic; P0.05) apparent ileal digestibility (AID) of crude protein (CP) and most AA, increased apparent total tract digestibility (ATTD) of Ca, P, K, Mg (linear and quadratic; P0.05), and Na (linear; P0.05), but decreased (linear and quadratic; P0.05) AID and ATTD of GE. In all phases, ileal concentrations of inositol phosphate (IP) 6, IP5, IP4, and IP3 decreased (linear and quadratic; P0.05), whereas ileal inositol increased (linear and quadratic; P0.05) with increasing dietary phytase. However, as pig BW increased, AID of GE, CP, and AA increased (linear, P0.05), and the AID of a few AA (Met, Phe, Thr, Trp, Ala, Asp, Gly, and Ser) also increased quadratically (P0.05). The ATTD of GE, K, and Mg increased (linear and quadratic; P0.05), but ATTD of Ca and Na (linear; P0.05) and of P (linear and quadratic; P0.05) decreased as pig BW increased. Ileal IP6 and IP3 (linear and quadratic; P0.05) and ileal IP5 and IP4 (linear; P0.05) increased, whereas ileal inositol decreased (linear; P0.05) as pig BW increased. In conclusion, regardless of pig BW, increasing dietary phytase increased phytate degradation and inositol release in the small intestine, and consequently increased mineral and AA digestibility. Older pigs have reduced Ca, P, and Na digestibility, but increased K, Mg, AA, and GE digestibility compared with younger pigs. The efficiency of dietary phytase to degrade phytate appears to decrease as pigs get older.The influence of dietary phytase in pig nutrition is often investigated using pigs from 20 to 40 kg, but there are limited data to demonstrate that data obtained in young pigs can be extrapolated to pigs above 40 kg. Therefore, an experiment was conducted to determine effects of increasing phytase levels (0, 250, 500, 1,000, 2,000, and 4,000 phytase units) on phytate breakdown and nutrient digestibility of pigs throughout four productive phases (25 to 50 kg, 50 to 75 kg, 75 to 100 kg, and 100 to 125 kg). Results indicated that regardless of pig body weight, the digestibility of macro-minerals and most amino acids increased with increasing dietary phytase because of increased phytate breakdown.

The objective was to test the hypothesis that supplementation of diets for gestating sows with 25-hydroxycholecalciferol (25-OH-D3) or 1-hydroxycholecalciferol (1-OH-D3) affects serum biomarkers for bone and increases Ca and P balance and the apparent total tract digestibility (ATTD) of gross energy (GE), and the concentrations of digestible energy (DE) and metabolizable energy (ME) in diets without or with microbial phytase. Sixty multiparous sows were allotted to 1 of 6 diets. Diets were formulated using a 3 × 2 factorial with 3 inclusions of supplemental vitamin D metabolite (no metabolite, 25-OH-D3, or 1-OH-D3) and 2 inclusion levels of microbial phytase (0 or 1,000 units). Sows were housed individually in metabolism crates and feces and urine were collected quantitatively. Results indicated that there was no difference in the ATTD of dry matter (DM) and GE and concentration of DE among the 3 diets containing microbial phytase, but the ATTD of DM and GE and concentration of DE was greater (P 0.05) in diets containing 1-OH-D3 compared with the diet without a vitamin D metabolite if phytase was not used (interaction; P 0.05). In diets without microbial phytase, ME was greater in diets containing either one of the 2 vitamin D metabolites than in the diet without a vitamin D metabolite, but among diets with microbial phytase, the ME of the 1-OH-D3 diet was less than of the 25-OH-D3 diet (interaction; P 0.05). No effect of microbial phytase on concentrations of DE and ME was observed. There was no interaction between supplementation of microbial phytase and vitamin D metabolites for Ca and P balances, and regardless of metabolite supplementation, use of microbial phytase increased (P 0.05) the ATTD and retention of Ca and P. Regardless of dietary phytase, the ATTD and retention of Ca and P increased (P 0.05) for sows fed a diet containing one of the vitamin D metabolites compared with sows fed the diet without a vitamin D metabolite. Serum biomarkers for bone resorption or bone tissue synthesis were not affected by experimental diets. In conclusion, the ATTD of DM and GE, concentrations of DE and ME, and Ca and P balance in phytase-free diets fed to sows in late gestation were increased by supplementation with 1-OH-D3 or 25-OH-D3, but no differences between the 2 vitamin D metabolites were observed. Supplementation of diets with microbial phytase increased Ca and P balance, but did not affect DE and ME of diets.The role of vitamin D is to increase absorption of calcium and phosphorus in the gastrointestinal tract and maintain serum concentrations of calcium, but dietary vitamin D needs to be converted to an active form by 2-hydroxylation steps that take place in the liver and the kidneys. The conversion efficiency to active vitamin D may be increased if pre-hydroxylated metabolites rather than vitamin D are provided, which also increases calcium and phosphorus utilization. In a previous experiment it was also demonstrated that a vitamin D metabolite increases energy absorption in gestating sows. It is possible that use of a vitamin D metabolite and phytase have additive effects and the hypothesis, therefore, was that supplementation of a vitamin D metabolite increases calcium and phosphorus balance and energy digestibility in diets fed to gestating sows without or with microbial phytase. Results indicated that in diets without phytase, the 2 vitamin D metabolites increased energy concentration in diets by increasing apparent energy digestibility. There was no interaction between supplementation of phytase and vitamin D metabolites for calcium and phosphorus balances. Use of phytase and vitamin D metabolites increased calcium and phosphorus digestibility and retention.

The beneficial effect of elevated concentrations of copper (Cu) on growth performance of pigs has been already demonstrated; however, their mechanism of action is not fully discovered. The objective of the present experiment was to investigate the effects of including Cu from copper sulfate (CuSO4) or monovalent copper oxide (Cu2O) in the diet of growing pigs on oxidative stress, inflammation, gene abundance, and microbial modulation. We used 120 pigs with initial body weight (BW) of 11.5 ± 0.98 kg in 2 blocks of 60 pigs, 3 dietary treatments, 5 pigs per pen, and 4 replicate pens per treatment within each block for a total of 8 pens per treatment. Dietary treatments included the negative control (NC) diet containing 20 mg Cu/kg and 2 diets in which 250 mg Cu/kg from CuSO4 or Cu2O was added to the NC. On day 28, serum samples were collected from one pig per pen and this pig was then euthanized to obtain liver samples for the analysis of oxidative stress markers (Cu/Zn superoxide dismutase, glutathione peroxidase, and malondialdehyde, MDA). Serum samples were analyzed for cytokines. Jejunum tissue and colon content were collected and used for transcriptomic analyses and microbial characterization, respectively. Results indicated that there were greater (P0.05) MDA levels in the liver of pigs fed the diet with 250 mg/kg CuSO4 than in pigs fed the other diets. The serum concentration of tumor necrosis factor-alpha was greater (P0.05) in pigs fed diets containing CuSO4 compared with pigs fed the NC diet or the diet with 250 mg Cu/kg from Cu2O. Pigs fed diets containing CuSO4 or Cu2O had a greater (P0.05) abundance of genes related to the intestinal barrier function and nutrient transport, but a lower (P0.05) abundance of pro-inflammatory genes compared with pigs fed the NC diet. Supplementing diets with CuSO4 or Cu2O also increased (P0.05) the abundance of Lachnospiraceae and Peptostreptococcaceae families and reduced (P0.05) the abundance of the Rikenellaceae family, Campylobacter, and Streptococcus genera in the colon of pigs. In conclusion, adding 250 mg/kg of Cu from CuSO4 or Cu2O regulates genes abundance in charge of the immune system and growth, and promotes changes in the intestinal microbiota; however, Cu2O induces less systemic oxidation and inflammation compared with CuSO4.Copper is a nonrenewable mineral resource that is essential for all biological organisms. After banning the antibiotics, copper has received considerable attention due to its antimicrobial properties that improve performance in animals when fed over the minimum requirement. The present study evaluated two sources of Cu (copper sulfate and monovalent copper oxide) compared with a nonsupplemented diet and the likely mechanism of action which leads to improved pig performance. Pigs fed high concentrations of copper sulfate showed increased liver oxidation and inflammatory indicators in the blood. Elevated concentrations of Cu improved intestinal epithelial barrier function, modulation of inflammatory responses, increased beneficial microbes, and reduced pathogens in the gut. Therefore, supplementation of high levels of Cu appears to be effective in promoting pig growth, but therapeutic doses of Cu sulfate increase the inflammatory response.

Our objective was to measure and compare apparent ileal digestibility, standard ileal digestibility, and true ileal digestibility of crude protein (CP) and amino acids (AA) in milk replacers (MR) containing all milk proteins (WPC) or with 50% of the CP provided by an enzyme-treated soybean meal (ESBM). A T-cannula was placed in the ileum of 9 Holstein calves (8 males and 1 freemartin female) at approximately 15 d of age. After 2 wk postsurgery, calves were randomly assigned to a 3 × 3 replicated Latin square with 5-d periods. Calves were fed twice daily at a rate of 2% (dry matter) of body weight (1.25 kg/d on average), reconstituted to 15% solids, and adjusted weekly. No starter was offered to minimize rumen development. Digesta samples were collected continuously during 12 h on d 4 and 5 of each period. Basal endogenous losses of AA and CP were estimated by feeding an N-free MR to each calf during 1 period. Total endogenous losses (basal + specific; ENDtotal) were estimated by multivariate regression of the chi-squared distances between digesta and reference protein AA profiles. Ileal digesta pH with the ESBM diet was lower than that with the WPC diet. According to the piecewise nonlinear model of pH fluctuation, digesta pH during ESBM decreased more slowly after feeding and reached its nadir later than with the WPC diet. Diet did not affect average daily gain, but calves on the ESBM diet showed a bigger increment of withers height and lower mean fecal scores. The basal endogenous losses of AA and CP were 13.9 ± 1.1 and 22.4 ± 1.1 g/kg of dry matter intake, respectively. The estimated ENDtotal of AA and CP was higher with ESBM than with WPC. Accordingly, apparent ileal digestibility and standard ileal digestibility of most AA, CP, and total AA were lower or tended to be lower with ESBM. However, true ileal digestibility did not differ between diets for CP and all AA except Ala and Ile, which were greater with WPC, and Arg, which tended to be greater with ESBM. In agreement with the estimated differences in ENDtotal, we found that flows of digesta DNA and crude mucin were greater with ESBM. Substitution of 50% of the protein from whey with enzymatically treated soybean meal did not affect major nutrient digestibility or calf growth and even improved fecal consistency. Adjusting digestibilities of CP and AA in MR by endogenous protein losses is crucial when comparing bioavailability of alternative proteins and milk proteins.

An experiment tested the hypothesis that isoquinoline alkaloids (IQ) in diets for weanling pigs formulated below amino acid (AA) requirements improves intestinal health and maintains growth performance of pigs compared with pigs fed a diet formulated at AA requirements. Two-hundred weanling pigs (6.11 ± 0.61 kg) were allotted to 4 dietary treatments with 5 pigs per pen and 10 pens per treatment for a 27 d, 2-phase experiment. Diets were arranged in a 2 × 2 factorial with AA at or 10% below requirements and with IQ at 0 or 120 mg/kg. Growth performance was calculated and plasma (d 14 and 27) and tissue samples (d 27) were collected. Data were analyzed with Proc MIXED of SAS using AA level, IQ inclusion, and the interaction as main effects. Pigs fed diets with IQ tended to have greater (P < 0.10) ADFI, whereas G:F was reduced if dietary AA were reduced (P < 0.05; Table 1). If AA were at requirements, lamina propria thickness in the jejunum was not affected by IQ inclusion, but if AA were below requirements, IQ decreased lamina propria thickness (interaction, P < 0.05). Villus height also tended to increase with dietary IQ (P < 0.10). Adding IQ to the diet that met AA requirements resulted in decreased plasma interleukin 4 and 10 on d 14; however, if IQ was in the reduced AA diet, the opposite was true (interaction, P < 0.05). If AA were below requirements, IQ tended to increase occludin in the jejunal mucosa, whereas if AA were at requirements, IQ tended to reduce occludin (interaction, P < 0.10). On d 26, reducing AA in the diet reduced (P < 0.05) plasma albumin. In conclusion, if AA are provided below the requirement, dietary IQ modulates systemic inflammation and improves intestinal function of weanling pigs.

The objective was to test the hypothesis that an increasing dose of a novel thermostable 6-phytase that was derived from E. coli and expressed in a Pichia Pastoris yeast (Superphy; Hanley International, LLC, Belmont, MA) increases apparent total tract digestibility (ATTD) of minerals and energy by pigs. Forty-eight barrows (initial weight: 22.61 kg) were housed in metabolism crates and fed 6 diets based on corn and soybean meal. The positive control (PC) diet contained P at the requirement. The negative control (NC) diet contained no feed phosphate, but contained 0, 250, 500, 1,000, or 2,000 phytase unit/kg. Feces were collected for 4 d after 5 d of adaptation. Dried and ground fecal samples were analyzed for dry matter, energy, Ca, P and other minerals. Data were analyzed using a model that included diet as fixed variable and contrast statements were used to compare PC and NC diets and to demonstrate linear and quadratic effects of phytase. Results indicated that ATTD of dry matter and energy and concentration of digestible energy in NC without phytase were greater (P < 0.05) than in PC, but ATTD of ash, K, Mg, Na, Cu, Fe, Mn, and Zn was not different between the 2 diets. There was no effect of phytase on ATTD of dry matter and energy or on digestible energy in diets. As dietary phytase increased, ATTD of ash and Mg increased (linear, P < 0.05) and ATTD of Ca and the standardized total tract digestibility (STTD) of P also increased (quadratic, P < 0.05), but ATTD of K, Na, Cu, Fe, Mn, and Zn was not affected by phytase. In conclusion, the novel enhanced E. Coli based phytase increased ATTD of Ca, P, and Mg and STTD of P if included in a diet containing Ca and P below requirements.

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 probiotic Bacillus toyonensis M15750 improve the apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of energy and nutrients when included in diets fed by weanling pigs. A control diet was formulated based on corn, soybean-meal, and distillers dried grains with solubles and a second diet was formulated by supplementing the probiotic Bacillus toyonensis M15750 (1 × 109 cfu/kg feed) to the control diet. Titanium dioxide (0.50 %) was added to the diets as an indigestible marker. Sixteen weanling barrows (10.7 ± 0.7 kg) that had a T-cannula in the distal ileum were allotted to the two diets with 8 replicate pigs per diet in a randomized complete block design with body weight being the blocking factor. Pigs were adapted to the diets and to the metabolism crates for 7 days, urine and fecal materials were collected during the following 4 days according to standard procedures using the marker-to-marker approach, whereas ileal digesta were collected for 8 h during the following 2 days. The AID and ATTD of energy and nutrients were calculated for each diet. The AID of dry matter and gross energy was greater (P < 0.05) and the AID of starch tended to be greater (P = 0.05) in the diet supplemented with the probiotic Bacillus toyonensis M15750 compared with the control diet (Table 1). However, no differences were observed for the ATTD of energy or nutrients between the 2 diets, which indicates that the increased digestibility in the small intestine of pigs fed the diet supplemented with Bacillus toyonensis M15750 was offset by a reduction in hindgut fermentation. These results indicate that inclusion of probiotic Bacillus toyonensis M15750 in diets for weanling pigs have the potential to improve the AID of dry matter, gross energy and starch.

An experiment was conducted to test two hypotheses: 1) reducing dietary Ca and P reduces gastric pH and diarrhea in weanling pigs; 2) negative effects of low Ca and P on pig growth performance may be overcome if phytase is added to the diets. A total of 320 weanling pigs (6.35 ± 0.87 kg) were allotted to eight corn-soybean meal-based diets in a randomized complete block design with five pigs per pen. Two phase 1 (days 1 to 14) control diets containing 100 or 50% of total Ca and digestible P relative to the requirement, and six diets in which 500, 2,000, or 16,000 units of phytase/kg feed (FTU) were added to each control diet were formulated. Phytase was assumed to release 0.16% total Ca and 0.11% digestible P. Common diets were fed in phases 2 (days 15 to 27) and 3 (days 28 to 42). Growth performance data were recorded within each phase. Data for fecal scores and gastrointestinal pH were recorded for phase 1. Colon content (day 14), the right femur (days 14 and 42), and blood samples (days −1, 14, 27, and 42) were collected from one pig per pen. In phase 1, reducing Ca and P did not reduce gastric pH or fecal score, but pigs fed the 50% diets had reduced (P < 0.05) average daily gain (ADG) and average daily feed intake (ADFI) compared with pigs fed the 100% diets. In both 50% and 100% diets, phytase above 500 FTU increased (P < 0.05) gain:feed ratio (G:F) and tended (P < 0.10) to reduce gastric pH of pigs. From days 1 to 42, pigs fed the 50% diets tended (P < 0.10) to have reduced ADG and ADFI compared with pigs fed the 100% diets, but among the 100% diets, pigs tended (P < 0.10) to have a linear increase in G:F as phytase level increased. Pigs fed the 50% diets had reduced (P < 0.05) concentrations of inositol phosphate esters (IP) in the colon and reduced bone ash (days 14 and 42) compared with pigs fed the 100% diets. Phytase did not affect bone ash or most blood metabolites. Concentrations of IP in the colon decreased, whereas plasma inositol increased (d 14; P < 0.05) in pigs fed diets with phytase (≥ 500 FTU). In pigs fed the 100% diets, IP in the colon linearly decreased (P < 0.05), but plasma inositol linearly increased (P < 0.05) with increasing levels of phytase. In conclusion, reducing Ca and P in diets for weanling pigs did not influence gastric pH or fecal score, but compromised growth performance and bone ash. However, regardless of dietary Ca and P, high doses of phytase increased phytate degradation and inositol absorption, which consequently increased G:F of pigs.

This study aimed at testing the hypothesis that greater inclusion of spray dried plasma (SDP) in diets improves growth performance, intestinal morphology, and reduces inflammation in weaned pigs. Four-hundred weaned pigs (body weight: 6.05 ± 0.80 kg) were allotted to a randomized complete block design with 5 diets and 2 blocks (16 pens/diet; 5 pigs/pen). Pens were not cleaned between groups to create a sanitation challenge. Phase-1 diets containing 0, 2, 4, 6, or 8% SDP were formulated. One pig per pen was sacrificed on d 14 and samples of intestinal tissue and mucosa were collected. Data were analyzed using PROC MIXED of SAS and linear, quadratic, and cubic contrast statements were used. During phase-1, ADG, ADFI, G:F, and body weight of pigs on d 14 increased (linear, P < 0.05) with increasing levels of SDP in the diet (Table 1). Villus width in the jejunum of pigs on d 14 tended to increase (linear, P < 0.10) with increasing inclusion of SDP (Table 2), and villus height:crypt depth tended to increase (quadratic, P < 0.10) with the greatest value observed for pigs fed a diet with 8% SDP. Secretory immunoglobulin A in the jejunal mucosa was decreased when 4 or 8% SDP was included in the diet (cubic, P < 0.05). Interleukin- (IL-) 2 (quadratic, P < 0.10) and IL-18 (cubic, P < 0.10) in the jejunal mucosa tended to decrease at 8% inclusion of SDP and IL-8 (linear, P < 0.10) tended to increase as SDP inclusion increased in the diet. In conclusion, the optimal inclusion of SDP in diets for weanling pigs was 8% as indicated by improvements in growth performance, but the collective intestinal morphology and health data do not result in a clearly conclusive optimum concentration in SDP.

The objective was to test the hypothesis that dietary P concentration and level of phytase influences basal endogenous loss of Ca in pigs. Seventy barrows (body weight: 17.66 kg) were housed in metabolism crates and allotted to 7 Ca-free diets containing corn, potato protein concentrate, and full-fat rice bran (0.27% phytate P). A positive control (PC) diet contained P at the requirement for digestible P for 11 to 25 kg pigs. Negative control (NC) diets were formulated by reducing concentration of digestible P by 0.15% and adding a novel consensus bacterial 6-phytase variant at 0, 250, 500, 1,000, 2,000, or 4,000 phytase units/kg diet. Feces and urine samples were collected separately for 4 d after 5 d of adaptation. Dried and ground fecal samples were analyzed for dry matter, Ca, and P and urine was analyzed for P. Data were analyzed using a model that included diet as fixed effect. Positive control and NC were compared using a contrast statement and linear and exponential effects of dietary phytase were tested. Results indicated that apparent total tract digestibility of dry matter was not affected by dietary P or phytase (Table 1). The basal endogenous loss of Ca was not affected by dietary P, but exponentially (P = 0.030) decreased as dietary phytase increased. Phosphorus retention (g/d) was greater (P < 0.001) in pigs fed PC compared with NC without phytase. The standardized total tract digestibility (STTD) of P exponentially (P < 0.001) increased as phytase increased; however, retention of P as % of absorbed P decreased (linear, P = 0.006) as phytase increased because the extra P absorbed as a result of phytase could not be retained due to the lack of Ca. In conclusion, increasing the phytase dose decreased basal endogenous loss of Ca and increased STTD of P.

Digestibilities of nutrients, especially protein, are crucial characteristics of milk replacers in a calf-rearing program. Endogenous synthesis of proteins and microbial fermentation in the large intestine alter apparent total-tract digestibility of AA. Therefore, collection of digesta samples at the end of the ileum is the only method to estimate true small intestinal digestibility of AA. The aim of this work was to evaluate the effectiveness of inserting a T-cannula into the distal ileum of preweaning calves for use in digestibility studies. A second objective was to evaluate the use of a "broken-line" statistical model to compare treatment effects on calf growth and digesta pH. A T-cannula was surgically installed in the terminal ileum of 2 calves approximately 5 cm anterior to the ileocecal junction at 15 d of age, and 2 paired noncannulated calves were used as controls. Cannulation did not affect mean body weight (BW), average daily gain, milk and water intakes, and body frame dimensions. However, final BW (89.2 vs. 94.6 kg) was lower and starter intake (0.06 vs. 0.21 kg/d) tended to be decreased in cannulated calves compared with control calves. No effects on health scores, rectal temperature, or the odds of incurring diarrhea or being medicated were observed. Flow of digesta (46.4 ± 0.04 g/h) increased linearly after feeding, whereas there was a quadratic effect of time on digesta pH, with the nadir at approximately 8.5 h postfeeding. The broken-line model successfully fitted daily fluctuations of pH and allowed us to detect differences in growth slopes between cannulated and control calves. Despite the expected negative effect on BW, we conclude that this technique permitted sampling of representative ileal digesta while allowing satisfactory growth and health of the calves.

An experiment was conducted to test the hypothesis that Val from a spray dried L-Val fermentation biomass (Val-FB; 64.4% L-Val) has a bioavailability of 100% relative to Val from L-Val (98% L-Val) when fed to weanling pigs. A Val-deficient basal diet containing 0.63% standardized ileal digestible (SID) Val was formulated. Six additional diets were prepared by supplementing the basal diet with 0.08%, 0.17%, or 0.25% L-Val or 0.12%, 0.25%, or 0.37% Val-FB to create experimental diets from both Val sources that contained 0.71%, 0.79%, or 0.87% SID Val. Two hundred twenty-four weaned pigs (6.87 ± 0.64 kg initial BW) were allotted to a randomized complete block design with 7 diets, 4 pigs per pen, and 8 replicate pens per diet. Diets were fed for 20 d. At the conclusion of the experiment, a blood sample from 1 pig per pen was analyzed for blood urea nitrogen (BUN) and plasma free AA. A linear regression model was used to estimate the relative bioavailability (RBV) of Val in Val-FB relative to Val from L-Val. Results indicated that the final BW and ADG were greater (P < 0.01) for pigs fed diets supplemented with Val-FB than pigs fed diets supplemented with L-Val. The ADFI decreased (linear, P ≤ 0.01), whereas G:F increased (linear, P < 0.01) by increasing inclusion of both Val sources in the diets. Regardless of source of dietary Val, BUN values were reduced (linear and quadratic, P < 0.01) as the concentration of Val in the diet increased. Pigs fed diets supplemented with L-Val had increased (linear and quadratic, P ≤ 0.05) concentrations of Val and Arg in plasma, and plasma concentrations of Ile, Leu, Lys, Ala, Cys, and Pro linearly increased (P < 0.05). There was also an increase (linear, P < 0.05) in plasma concentrations of Ile, Leu, Met, Ala, Asp, Cys, and Pro as Val-FB was added to the diets, and the concentration of Val in plasma increased (linear and quadratic, P < 0.05). Using L-Val as the standard, the RBV of Val in Val-FB as determined by ADG, G:F, and final BW was 146%, 135%, and 143%, respectively, with 95% confidence intervals of 99% to 191%, 83% to 187%, and 70% to 217%, respectively. In conclusion, the linear regression estimated a RBV of at least 100% for Val in Val-FB relative to Val from L-Val, and pigs fed diet supplemented with Val-FB had greater final BW, ADG, and G:F than pigs fed diets supplemented with the same amount of Val from L-Val.

Two experiments were conducted to test the hypothesis that a corn-expressed phytase increases growth performance, bone measurements, and nutrient digestibility by young growing pigs, if added to diets that are deficient in Ca and P. In Exp. 1, 60 pigs (initial BW: 10.78 ± 0.67 kg) were randomly allotted to 6 dietary treatments that included a positive control diet (PC; 0.70% total Ca and 0.60% total P) and a negative control diet (NC; 0.50% total Ca and 0.42% total P). Four additional diets were formulated by supplementing the NC diet with 250, 500, 1,000, or 1,500 phytase units (FTU)/kg. Diets were fed for 28 d and the individual BW of pigs on days 1 and 28 were recorded. Fecal samples were collected from days 25 to 27 to calculate apparent total tract digestibility (ATTD) of Ca and P. On the last day of the experiment, all pigs were euthanized, and the left femur was removed and analyzed for ash, Ca, and P. Results indicated that growth performance, ATTD of Ca and P, and bone ash measurements were reduced (P < 0.05) in NC fed pigs compared with PC fed pigs. However, growth performance, ATTD of Ca and P, and bone ash measurements were improved (linear and quadratic, P < 0.05) by including increasing concentrations of phytase to the NC diet. In Exp. 2, experimental procedures were similar to those used in Exp. 1. Forty-eight pigs (initial BW: 11.15 ± 0.85 kg) were randomly allotted to 6 dietary treatments in a 28-d experiment. Treatments included a PC diet, an NC diet, and 4 diets in which 500 or 1,000 FTU/kg of either the corn-expressed phytase or a commercial microbial phytase were added to the NC diet. Pigs fed the NC diet had reduced (P < 0.01) final BW, ADG, G:F, and bone ash concentrations compared with pigs fed the PC diet. When 500 FTU/kg phytase was fed, no differences were observed in growth performance or bone ash measurements between phytase sources, and there were no differences in growth performance among pigs fed 1,000 FTU/kg of either phytase source or the PC diet. However, regardless of concentration or source of phytase, pigs fed the PC diet had greater (P < 0.001) amount of bone ash, bone Ca, and bone P compared with pigs fed phytase diets. In conclusion, the corn-expressed phytase is effective in improving growth performance, Ca and P digestibility, and bone measurements in pigs fed diets that are deficient in Ca and P.

Two experiments were conducted to test the hypothesis that standardized total tract digestibility (STTD) of Ca and the response to microbial phytase is constant among different sources of Ca carbonate and that the STTD of Ca is constant among different sources of dicalcium phosphate (DCP) when fed to growing pigs. In Exp. 1, 80 pigs (initial BW: 19.0 ± 1.9 kg) were randomly allotted to 10 diets and 2 blocks with 4 pigs per diet in each block. Four sources of Ca carbonate were used, and each source was included in a diet without microbial phytase and a diet with microbial phytase (500 units/kg diet). Two Ca-free diets without or with microbial phytase were also formulated. Feed allowance was 2.7 times the maintenance energy requirement for ME and daily feed allotments were divided into 2 equal meals. The initial 4 d of each period were considered the adaptation period to the diets followed by 4 d of fecal collection using the marker-to-marker procedure. Pigs fed diets containing exogenous phytase had lower (P < 0.05) basal endogenous loss of Ca compared with pigs fed diets containing no phytase. There were no interactions between phytase and source of Ca carbonate. Values for STTD of Ca were greater (P < 0.05) for diets containing microbial phytase (77.3% to 85.4%) compared with diets without exogenous phytase (70.6% to 75.2%), and values for STTD of Ca differed (P < 0.05) among the 4 sources of Ca carbonate. In Exp. 2, 40 pigs (initial BW: 14.9 ± 1.3 kg) were allotted to a completely randomized design with 5 diets and 8 replicate pigs per diet. A basal diet in which all Ca was supplied by Ca carbonate was formulated. Three diets were formulated by adding 3 sources of DCP to the basal diet and a Ca-free diet was also used. Feeding and collection methods were as described for Exp. 1. Results indicated that values for STTD of Ca and ATTD of P were not different among diets, indicating that under the conditions of this experiment, the digestibility of Ca and P in DCP appears to be constant regardless of origin of DCP. In conclusion, use of microbial phytase reduces the basal endogenous loss of Ca and increases Ca digestibility in Ca carbonate. The STTD of Ca varies among sources of Ca carbonate, regardless of phytase inclusion, but that appears not to be the case for the STTD of Ca in different sources of DCP.

Two experiments were conducted to test the hypothesis that different watering options affect the standardized ileal digestibility (SID) of amino acids (AA), apparent total tract digestibility (ATTD) of dry matter (DM) and gross energy (GE), and concentration of net energy (NE) by growing pigs. A corn-soybean meal-based diet was used in both experiments. There were 3 treatments: 1) dry feeder plus a water nipple located outside the feeder, 2) wet-dry feeder with the water nipple inside the feeder, and 3) combined system with a water nipple both inside the feeder and also an outside nipple. In Exp. 1, pigs (n = 6; initial weight = 27.53 kg) that were equipped with a T-cannula in the distal ileum were allotted to the 3 treatments using a replicated 3 × 3 Latin square design with 6 pigs and three 7-d periods. All pigs were fed an N-free diet for an additional period to determine basal endogenous losses of AA. Chromic oxide was added to all diets and ileal digesta were collected according to standard procedures. In Exp. 2, 24 pigs (initial weight = 50.23 kg) were allotted to the 3 treatments using a replicated 3 × 3 Latin square design with 6 chambers (i.e., 4 pigs per chamber) and three 15-d periods. Oxygen consumption and CO2 and CH4 productions were measured during fed and fasting states and fecal and urine samples were collected. In both experiments, pigs were allowed ad libitum access to feed and water. Results indicated that there were no differences among watering options for SID of AA, feed intake, total and fasting heat production, ATTD of DM and GE, or NE in diet. In conclusion, different watering options did not affect the digestibility of AA, DM, and GE and concentration of NE in a corn-soybean meal diet fed to growing pigs.

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 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.

The objective was to test the hypothesis that growth performance and carcass characteristics of pig 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 4 diets that were arranged in a 2 × 2 factorial design with 2 sources of DDGS (cold-fermented and conventional DDGS) and 2 diet forms (meal and pellets). Pigs were fed phase 2 diets from d 7 to 21 and phase 3 diets from d 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 d 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 2 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. However, no differences between the 2 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) gain to feed ratio compared with pigs fed the pelleted diets. There were no differences between the 2 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 gain to feed ratio and greater back fat than pigs fed meal diets.

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.

The objective was to determine correlations between individual and total body bone ash to identify the bone that is most representative of total body bone ash. Ten gilts and 10 barrows (BW: 40.8 kg) were allotted to 2 diets. The 2 diets were formulated to contain 60% or 100% of the requirement for standardized total tract digestible (STTD) P and STTD Ca with a STTD Ca:STTD P of 1.90:1, which is believed to maximize bone ash. Body weight and the amount of feed consumed by pigs were recorded on d 14 and 28 and carcass characteristics of all pigs were determined on d 28. Metacarpals, metatarsals, femur, tibia, fibula, ribs, and all other bones from the carcass were collected separately, defatted, and ashed. The statistical model included diet as fixed effect and sex and BW within sex as random effects. Correlation coefficients between total and individual bones were determined. Overall, pigs fed the diet formulated to meet 100% of the requirement for Ca and P had greater (P < 0.05) average daily gain and gain:feed compared with pigs fed the diet with 60% Ca and P, but there was no difference in average daily feed intake (Table 1). There was no effect of dietary Ca and P on carcass characteristics of pigs. Weights of bone ash were greater (P < 0.05) for pigs fed the diet with 100% rather than 60% of the requirement for Ca and P. Correlation coefficients between the weight of total bone ash and the weight of ashed metacarpals, metatarsals, and tibia were greater than 0.950 (P < 0.05), whereas correlation coefficient for femur, fibula, and ribs were less than 0.929 (P < 0.05). In conclusion, metacarpals, metatarsals, and tibia were more representative of total body bone ash compared with femur, fibula, and ribs.

An experiment was conducted to test the hypothesis that spray dried plasma (SDP) increases the standardized ileal digestibility (SID) of CP and AA from other ingredients in diets for young pigs, which may result in a lack of additivity in such diets. Thirty ileal cannulated barrows (body weight: 9.30 ± 0.63 kg) were randomly allotted to a triplicated 10 × 3 Youden square design with 10 diets and three 7-d periods. Diets from four regions were formulated: the U.S.A. [corn-soybean meal (SBM)-based diet], the European Union (corn-wheat-barley-SBM-based diet), Canada (wheat-barley-SBM-fermented SBM-based diet), and Asia (corn-rice-SBM-fermented SBM-based diet). Diets from each region contained 0 or 6% SDP. Differences between measured and predicted SID of CP and AA in diets with SDP were calculated. Data were analyzed using PROC MIXED of SAS as a 2 × 4 factorial with 2 levels of SDP and 4 regions. There was an SDP by region interaction for the measured SID of CP and all AA, except Lys (Table 1). When SDP was added to the U.S.A, the European Union, and Asia diets, the SID of CP and AA was not increased. The SID of CP and AA, except Lys, was greater (P < 0.05) in the Canada diet with SDP than without SDP. The measured SID of CP and AA was consistent with predicted values for the European Union and Asia diets (Table 2). The measured SID of Trp was less (P < 0.05) than predicted for the U.S.A. diet, and the measured SID of CP and all indispensable AA was greater (P < 0.05) than predicted in the Canada diet. In conclusion, addition of 6% SDP to wheat-barley-based diets may increase SID of CP and AA, and therefore, the SID of CP and AA in diets containing SDP may be greater than predicted.

An experiment was conducted to test the hypothesis that increasing concentrations of dietary Val, Ile, or Trp alone or in combination will alleviate negative effects of excess dietary Leu on N balance of growing pigs. Seventy-two barrows (initial body weight: 33.9 ± 2.6 kg) were housed in metabolism crates and randomly assigned to 1 of 8 diets and 3 blocks with 3 pigs per diet in each block in a 12-d experiment. Treatments were arranged in a 2 × 2 × 2 factorial with the main effects of L-Val (0 or 0.1%), L-Ile (0 or 0.1%), and L-Trp (0 or 0.05%) that were added to a basal diet containing corn and a high-protein corn product (48% crude protein; 5.9% Leu). The basal diet contained 1.00 % standardized ileal digestible (SID) Lys and 171% SID Leu:Lys. Data were analyzed using the PROC MIXED of SAS with concentrations of Val, Ile, and Trp, and all interactions as main effects and replicate as a random effect. No 3-way interactions were observed (Table 1). Results indicated that fecal N output increased if Ile was added to diets without added Val, but that was not the case if Val was added (interaction, P < 0.05). Addition of Ile to diets reduced N retention, but N retention increased with Trp addition to diets without Val addition, but not if Trp was added to diets with added Val (interaction, P < 0.05). The biological value of protein increased if Trp was added to diets without addition of Ile, but if Ile was added, Trp addition did not increase the biological value of protein (interaction, P < 0.05). In conclusion, adding Ile to a diet with excess Leu reduced N retention, but if Trp was added alone or in combination with Ile or Val, N retention increased.

The hypothesis that apparent ileal digestibility (AID), basal endogenous losses, and standardized ileal digestibility (SID) of AA are not affected by adding acid to collection containers or bags used to collect ileal digesta from pigs was tested. Twenty-four barrows (initial BW: 77.8 kg) that had a T-cannula installed in the distal ileum were fed diets for three 7-d periods. Corn, soybean meal, and wheat middlings were the sole AA sources in each diet and an N-free diet was also used. Within each period, each of the 4 diets was fed to 6 pigs. Among the 6 pigs, digesta from 3 pigs were collected in bags containing no HCl, whereas 40 mL of 3N HCl was included in the bags used to collect digesta from the remaining 3 pigs. Every other bag collected from each pig was emptied into a container without adding HCl, whereas the remaining bags were added to a container along with 40 mL of 3N HCl for each bag. All digesta were stored at –20 °C immediately after collection. Data were first analyzed using a model that included feed ingredient, HCl in bags, HCl in containers, and all 2-way and 3-way interactions as fixed effects. No 3-way interactions were significant, and data were, therefore, analyzed independently for each diet as a 2 × 2 factorial. Results indicated that there were no interactions between adding HCl to collection bags and to containers, and no effects of adding HCl to collection bags or containers for AID, basal endogenous losses, or SID of most AA were observed (Table 1). In conclusion, if digesta are stored at –20 °C immediately after collection, it is not necessary to add acid to digesta collection bags or collection containers.

The objective was to determine correlations between individual bones and total body bone ash to identify the bone that is most representative of total body bone ash in growing pigs. Twenty growing pigs were allotted to 1 of 2 diets that were formulated to contain 60% or 100% of the requirement for standardized total tract digestible (STTD) P. Both diets had an STTD Ca to STTD P ratio of 1.90:1. Growth performance and carcass weights were determined. Metacarpals, metatarsals, femur, tibia, fibula, 3rd and 4th ribs, and 10th and 11th ribs, and all other bones from the left half of the carcass were collected separately. Each bone was defatted and ashed. Pigs fed the diet containing 100% of required Ca and P had greater (P < 0.05) average daily gain, gain to feed, and ash concentration (%) in total and all individual bones except femur and fibula compared with pigs fed the diet containing 60% of required Ca and P. Calcium and P concentrations in bone ash were not affected by dietary treatments. Weights (g) of bone ash, bone Ca, and bone P were greater (P < 0.05) or tended to be greater (P < 0.10) for pigs fed the diet containing 100% of required Ca and P. Correlation coefficients between the weight of ashed metacarpals, metatarsals, and tibia and the weight of total bone ash were >0.95. In conclusion, metacarpals, metatarsals, and tibia were more representative of total body bone ash compared with other bones.

An experiment was conducted to test the hypothesis that formulating diets for pigs based on a ratio between standardized total tract digestible (STTD) Ca and STTD P instead of total Ca and STTD P does not decrease Ca retention, but increases P utilization. Forty barrows (59.4 ± 3.8 kg) were individually housed in metabolism crates and allotted to four corn-soybean meal-based diets in a randomized complete block design with two blocks and five pigs per diet in each block. Diets were formulated using a 2 × 2 factorial design with two diet formulation principles (total Ca or STTD Ca) and two inclusion levels of microbial phytase (0 or 500 units per kg of feed). Phytase was assumed to release 0.11% STTD P and 0.16% total Ca. Diets were formulated based on requirements for total Ca and STTD P or a ratio between STTD Ca and STTD P of 1.25:1. Diets were fed for 11 d and fecal and urine samples were collected from feed provided from day 6 to day 10. Interactions (P < 0.05) between diet formulation principle and phytase level were observed for Ca intake, Ca in feces, Ca absorbed, Ca retained, P digestibility, P absorbed, and P in urine. Phytase increased (P < 0.05) the digestibility of Ca in both total Ca and STTD Ca diets. Without phytase, Ca intake, Ca in feces, and Ca absorbed was greater (P < 0.05) from pigs fed total Ca diets than from pigs fed STTD Ca diets, but P absorbed, P digestibility, and P in urine was greater (P < 0.05) from pigs fed STTD Ca diets than from pigs fed total Ca diets. However, in the presence of phytase, no differences between diet formulation principles were observed in these variables. Regardless of phytase, Ca in urine was lower (P < 0.05) from pigs fed STTD Ca diets than from pigs fed total Ca diets. There were no differences in Ca retention between pigs fed STTD Ca diets and total Ca diets, but pigs fed total Ca diets retained less (P < 0.05) Ca if diets contained phytase. No differences in P retention were observed between diet formulation principles, but pigs fed non-phytase diets retained more (P < 0.05) P than pigs fed diets with phytase. In conclusion, because diets formulated based on STTD Ca contain less Ca than total Ca diets, pigs fed STTD Ca diets excreted less Ca in urine, but retention of Ca was not affected. Formulating non-phytase diets based on STTD Ca instead of total Ca increased P absorption, which confirms the detrimental effect of excess Ca on P digestibility. However, P retention was not improved if pigs were fed STTD Ca diets.

The objective was to test the hypothesis that there is no effect of origin or processing procedure on the standardized ileal digestibility (SID) of amino acids (AA) and crude protein (CP) in sunflower co-products. Six sources of sunflower meal (SFM) and 1 source of sunflower expellers (SFE) were obtained from Ukraine, Italy, Hungary, and the U.S. Each source of SFM or SFE was the only source of CP and AA in 1 diet and an N-free diet was also used for a total of 8 diets. Eight barrows (body weight: 28.5 ± 2.4 kg) had a T-cannula installed in the distal ileum and were allotted to 1 of the 8 diets using an 8 × 8 Latin square design with 8 periods. The Lys:CP ratio in the 6 sources of SFM ranged from 3.10 to 3.96% with CP concentrations ranging from 27.34 to 36.75%. Crude protein in SFE was 26.87% and the Lys:CP ratio was 3.51%. Concentrations of acid hydrolyzed ether extract in the 6 sources of SFM ranged from 0.60 to 3.11%, but SFE contained 8.77%. Results indicated that the SID of CP was lower (P < 0.05) in SFM from Hungary compared with all other sources of SFM except for 1 of the sources from Ukraine. There were no differences in the SID of Lys, Met, and Trp among sources of SFM, but for most of the remaining indispensable AA, the SFM from Hungary had less (P < 0.05) SID than the other sources. However, only few differences in SID of indispensable AA were observed among the other sources of SFM, but the SID of CP and all AA except Trp was greater (P < 0.05) in SFE compared with SFM. In conclusion, there were only few differences in the SID of the first limiting AA among SFM obtained from Ukraine, Hungary, Italy, and the U.S., but the SID of CP and AA was greater in SFE than in SFM indicating that processing of sunflower seeds influence the nutritional value.

An experiment was conducted to test the hypothesis that inclusion of Cu oxide (Cu2O) in diets for growing–finishing pigs improves body weight (BW) and bone mineralization, and reduces accumulation of Cu in the liver compared with pigs fed diets containing Cu sulfate (CuSO4). Two hundred growing pigs (initial BW: 11.5 ± 0.98 kg) were allotted to a randomized complete block design with 2 blocks of 100 pigs, 5 dietary treatments, 5 pigs per pen, and a total of 8 pens per treatment. Treatments included the negative control (NC) diet that contained 20 mg Cu/kg, and 4 diets in which 125 or 250 mg Cu/kg from CuSO4 or Cu2O were added to the NC diet. The experiment was divided into 4 phases and concluded when pigs reached market weight. Pig weights were recorded on day 1 and at the end of each phase and feed provisions were recorded throughout the experiment. On the last day of phases 1 and 4, 1 pig per pen was sacrificed to obtain samples of liver and spleen tissue, and the right metacarpal was collected. Results indicated that pigs fed diets containing 250 mg Cu/kg from CuSO4 had greater BW at the end of phases 1 and 2 than pigs fed NC diets. Pigs fed diets containing 250 mg Cu/kg from Cu2O had greater (P < 0.05) BW at the end of phases 1, 2, 3, and 4 compared with pigs fed NC diets, and these pigs also had greater BW at the end of phases 3 and 4 than pigs fed all other diets. Pigs fed the diets with 250 mg Cu/kg tended to have greater (P < 0.10) feed intake than pigs fed the NC diet at the end of phase 2, and for the overall experimental period, pigs fed diets containing 250 mg Cu/kg from Cu2O had greater (P < 0.05) feed intake than pigs on all other treatments. However, no differences in gain:feed ratio were observed among treatments. Copper accumulation in liver and spleen increased with Cu dose, but at the end of phase 1, pigs fed 250 mg Cu/kg from CuSO4 had greater (P < 0.05) Cu concentration in liver and spleen than pigs fed 250 mg Cu/kg from Cu2O. Pigs fed diets containing 250 mg Cu/kg from Cu2O had greater (P < 0.05) quantities of bone ash and greater (P < 0.05) concentrations of Ca, P, and Cu in bone ash than pigs fed NC diets or the 2 diets containing CuSO4, but Zn concentration in bone ash was less (P < 0.05) in pigs fed diets containing 250 mg Cu/kg from Cu2O. To conclude, supplementing diets for growing pigs with Cu2O improves growth performance and bone mineralization with less Cu accumulation in liver compared with pigs fed diets containing CuSO4.

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 the requirement for Ca expressed as a ratio between standardized total tract digestible (STTD) Ca and STTD P obtained in short-term experiments may be applied to pigs fed diets without or with microbial phytase from 11 to 130 kg. In a 5-phase program, 160 pigs (body weight: 11.2 ± 1.8 kg) were randomly allotted to 32 pens and 4 corn–soybean meal-based diets in a 2 × 2 factorial design with 2 diet formulation principles (total Ca or STTD Ca), and 2 phytase inclusion levels (0 or 500 units/kg of feed) assuming phytase released 0.11% STTD P and 0.16% total Ca. The STTD Ca:STTD P ratios were 1.40:1, 1.35:1, 1.25:1, 1.18:1, and 1.10:1 for phases 1 to 5, and STTD P was at the requirement. Weights of pigs and feed left in feeders were recorded at the end of each phase. At the conclusion of phase 1 (day 24), 1 pig per pen was euthanized and a blood sample and the right femur were collected. At the end of phases 2 to 5, a blood sample was collected from the same pig in each pen. At the conclusion of the experiment (day 126), the right femur of 1 pig per pen was collected and carcass characteristics from this pig were measured. No interactions were observed between diet formulation principle and phytase inclusion for growth performance in any phase and no differences among treatments were observed for overall growth performance. Plasma Ca and P and bone ash at the end of phase 1 were also not influenced by dietary treatments. However, on day 126, pigs fed nonphytase diets formulated based on total Ca had greater bone ash than pigs fed STTD Ca-based diets, but if phytase was used, no differences were observed between the 2 formulation principles (interaction P < 0.05). At the end of phases 2 and 3, pigs fed diets without phytase had greater (P < 0.05) plasma P than pigs fed diets with phytase, but no differences were observed at the end of phases 4 and 5. A negative quadratic effect (P < 0.05) of phase (2 to 5) on the concentration of plasma Ca was observed, whereas plasma P increased (quadratic; P < 0.05) from phases 2 to 5. However, there was no interaction or effect of diet formulation principle or phytase inclusion on any carcass characteristics measured. In conclusion, STTD Ca to STTD P ratios can be used in diet formulation for growing-finishing pigs without affecting growth performance or carcass characteristics and phytase inclusion ameliorates bone resorption caused by low dietary Ca and P.

Objective: The hypothesis was that apparent ileal digestibility (AID), basal endogenous losses, and standardized ileal digestibility (SID) of amino acids (AA) are not affected by adding acid to collection containers or bags used to collect ileal digesta from pigs.Methods: Twenty-four growing barrows (initial body weight: 77.8±4.5 kg) that were fitted with a T-cannula in the distal ileum were fed diets for three 7-d periods. An N-free diet and 3 diets containing corn, soybean meal, or wheat middlings as the sole source of AA were used. Within each period, each of the 4 diets were fed to 6 pigs. Among the 6 pigs, digesta from 3 pigs were collected in bags containing no HCl, whereas 40 mL of 3 N HCl was included in the bags used to collect digesta from the remaining 3 pigs. Every other bag collected from each pig was emptied into a container without adding HCl, whereas the remaining bags were added to a container along with 40 mL of 3 N HCl for each bag. All digesta were stored at –20°C immediately after collection. Data were analyzed using a model that included feed ingredient, HCl in bags, HCl in containers, and all 2-way and 3-way interactions as fixed effects. No 3-way interactions were significant, and data were, therefore, reanalyzed independently for each diet as a 2×2 factorial.Results: There were no interactions between adding HCl to collection bags and to containers, and no effects of adding HCl to collection bags or containers for AID, basal endogenous losses, or SID of most AA were observed.Conclusion: It is not necessary to add acid to digesta collection bags or collection containers if ileal digesta are stored at –20°C immediately after collection.

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.

Feed phosphates are included in swine diets to meet the requirements of P. Two products are predominantly used for this purpose, commercial monocalcium phosphate (MCP) and dicalcium phosphate (DCP). Theoretically, pure MCP should contain 26.5% P but commercial sources of MCP contain around 21 % P. The reason there is less P in commercial sources is that these sources are contaminated with calcium carbonate and other minerals. In addition, feed grade phosphates called MCP in reality is a mixture of MCP and DCP, which also contributes to the reduced P. To determine the complete composition of commercial MCP, seven sources of MCP were procured. All sources were analyzed for most common minerals that may be present in feed phosphates (Table 1) Results indicate that the composition of minerals is relatively stable among the different sources of MCP, indicating that the process to produce feed grade phosphates does not result in much variability. However, none of the commercial feed grade phosphates contained close to 26.5% P, which would be expected in a pure source.

An experiment was conducted to test the hypothesis that Cu hydroxychloride (IntelliBond CII, Micronutrients, LLC, Indianapolis, IN) improves growth performance by upregulating the mRNA transcription of genes involved in lipid metabolism of pigs. 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 control diet based on corn, soybean meal, and distillers dried grains with solubles that included Cu to meet the requirement. A second diet was formulated by adding 150 mg Cu/kg from Cu 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. 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 gain and gain:feed were greater (P < 0.05) for pigs fed the diet containing Cu hydroxychloride compared with pigs fed the control diet (Table 1). Pigs fed the diet supplemented with Cu hydroxychloride had increased (P < 0.05) abundance of cluster of differentiation 36 in liver and increased (P < 0.05) abundance of fatty acid binding protein 4 and lipoprotein lipase in subcutaneous adipose tissue. Inclusion of Cu hydroxychloride also tended to increase (P < 0.10) abundance of fatty acid binding protein 1, peroxisome proliferator-activated receptor alpha, and carnitine palmitoyl transferase 1 B in liver, skeletal muscle, and subcutaneous adipose tissue, respectively. In conclusion, supplementation of Cu hydroxychloride to the control diet improved growth performance and may affect signaling pathways associated with lipid metabolism by upregulating abundance of some genes involved in post-absorptive metabolism of lipids.

An experiment was conducted to test the hypothesis that hybrid rye can replace corn in gestation and lactation diets without negatively affecting sow and litter performance. For gestation and lactation, a corn-soybean meal control diet and 3 additional diets in which hybrid rye replaced 25, 50, or 75% of corn were formulated. Sows were randomly allotted by parity to treatments, with 45 replicate sows per treatment. Sows were individually housed for the duration of the experiment. Sow BW were recorded on d 7 and d 105 of gestation, as well as within 24 h after farrowing and on the day of weaning (approximately d 20 of lactation). Number and weights of live born, still born, and mummified piglets were determined within 24 h of farrowing. Data related to piglet mortality were analyzed using SAS Proc Glimmix with binomial distribution, whereas all other data were analyzed using Proc Mixed. The statistical models included the fixed effects of diet and parity. Diet did not influence sow BW or sow ADG at any point in the experiment (Table 1). Diet did not affect number or weights of total, live, or still born pigs, but there was an increase and then a reduction in the number of pigs weaned, litter wean weight, and litter ADG as the inclusion of hybrid rye in the diets increased (quadratic, P < 0.05). Piglet mortality, as well as the proportion of piglets crushed by sows, tended (P < 0.10) to be quadratically reduced as hybrid rye was added to the diet. In conclusion, replacing corn with hybrid rye in gestation and lactation diets had no effect on sow BW changes nor on number or birthweights of piglets, and overall, diets with 25% and 50% corn replacement rate with rye resulted in improved sow lactation performance.

Reducing dietary CP with crystalline AA supplementation has been proposed as a nutritional strategy to control post-weaning diarrhea in response to global concerns about negative effects of sub-therapeutic use of antibiotics. One hundred eighty weaned pigs (5.53 ± 0.88 kg) were randomly allotted to 3 treatments with 12 replicate pens per treatment for 28 d. Treatments included antibiotic-free, corn-soybean meal diets containing 22% and 19% CP, adequate in AA, and a 16% CP diet that provided AA below the requirement. Daily feed provisions and pig weights were recorded weekly. Fecal scores were assessed every other day. Blood samples were collected on d 1, 6, 13, 20, and 27 and 1 pig per pen was euthanized on d 12. Data for growth performance, fecal scores, and intestinal pH were analyzed by contrast statements and data for blood characteristics were analyzed using repeated measures. Results indicated that reducing dietary CP linearly (P ≤ 0.05) reduced overall ADG, G:F, body weight, and fecal scores of pigs. Reduction in dietary CP resulted in greater reduction in BUN after d 13 (treatment × day interaction, P ≤ 0.05). Total protein, albumin, and vitamin A and E in serum were lowest (P ≤ 0.05) on d 13, and pigs fed 16% CP had reduced (P ≤ 0.05) albumin compared with pigs fed other diets. The pH in the ileum was reduced (P ≤ 0.05) as dietary CP decreased but pH in the colon of pigs fed 19% CP was the lowest (P < 0.05) at d 13. In conclusion, reducing CP to 19% and 16% in antibiotic-free diets for weanling pigs reduces fecal score without impairing the growth performance during the first 14 d after weaning. However, additional strategies are needed to maintain growth performance during the next two weeks.