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Background: The "Digestible Indispensable Amino Acid Score" (DIAAS) method measures protein quality in human foods. Animal‐based products generally have high protein quality, but DIAAS values for some pork products are not available. Therefore, the objective of this experiment was to determine standardized ileal digestibility (SID) of amino acids (AA) and DIAAS values for pork products, including three types of pork cuts, Italian hams, and sausages, and to test the hypothesis that all pork products have DIAAS equal to or greater than 100. Results: The mean SID of the indispensable AA in all pork products was above 90% and indicated excellent digestibility. For children from 6 months to 3 years old and individuals older than 3 years, prosciutto had greater (p < 0.05) DIAAS than all other pork products. Tenderloin and Coppa had greater (p < 0.05) DIAAS than back ribs, shoulder butt, chorizo, and bratwurst. There were no limiting AA in any of the pork products (DIAAS >100) with the exception that sulfur AA (SAA: methionine + cysteine) were limiting in chorizo for children from 6 months to 3 years old (DIAAS = 99). Conclusion: With the exception of chorizo for children less than 3 years old, all pork products have "excellent" protein quality for individuals older than 6 months of age, with DIAAS greater than 100. Pork proteins can, therefore, complement proteins with low quality to produce a meal that is adequate in all AA. [ABSTRACT FROM AUTHOR]

BACKGROUND: Rapeseed protein isolate is used in the food industry, and heating is often used during rapeseed processing. However, the digestible indispensable amino acid score (DIAAS) for heat‐treated rapeseed protein isolate is unknown. The present study aimed to test the hypothesis that heating rapeseed protein isolate improves protein quality resulting in DIAAS that is greater than for pea and rice protein concentrates, and comparable to that of soy and whey protein isolates. RESULTS: Standardized ileal digestibility (SID) of amino acids (AA), except leucine and methionine, was not different between heat‐treated rapeseed protein isolate and soy protein isolate, but SID of most AA was greater (P < 0.001) for heat‐treated rapeseed protein isolate than for brown rice protein concentrate, pea protein concentrate, rapeseed protein isolate and soy protein isolate, but not whey protein isolate. Non‐heated rapeseed protein isolate had a reduced (P < 0.001) DIAAS for 6‐month‐old to 3‐year‐old children compared with soy protein isolate, but this was greater (P < 0.001) than for pea and brown rice protein concentrates. The DIAAS for heat‐treated rapeseed protein isolate was greater (P < 0.001) than for non‐heated rapeseed protein isolate for all age groups. Heat‐treated rapeseed protein isolate and whey protein isolate had a DIAAS > 100 for individuals older than 3 years. CONCLUSION: Rapeseed protein isolate had a DIAAS comparable to soy protein isolate, but heat‐treated rapeseed protein isolate and whey protein isolate had DIAAS ≥ 100, qualifying these proteins as 'excellent'. Rice and pea protein concentrates had DIAAS < 75. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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, P < 0.05) 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, P < 0.05) the AID of dry matter and minerals (i.e. Ca, P, K, Mg, Cu) in the diets. Likewise, a linear increase (P < 0.05) 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, P < 0.01) the AID of gross energy (GE) and starch in the diets. A quadratic (P < 0.05) 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; P < 0.05) 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Animal Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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. [ABSTRACT FROM AUTHOR]

Soybean meal (SBM) from China, Argentina, Brazil, the USA and India was collected to evaluate their performances in the diet of Pacific white shrimp. SBM samples were analysed for proximate composition, amino acid profiles, sugars, fibres, macro and micro minerals. A growth trial was conducted using SBM‐based test diets (350 g kg−1 protein and 80 g kg−1 lipid), and a digestibility trial was carried out from digestibility diets formulated by mixing the basal diet and test ingredients (70:30) on a dry matter basis. Significantly higher growth (as standardized Thermal growth coefficient) was observed in shrimp fed SBM from China over Brazilian SBM. However, growth performances of shrimp fed SBM sourced from USA, Argentina and India were not different to that of Chinese and Brazilian SBM. No significant differences were observed for apparent dry matter, energy and protein digestibility coefficients (<0.05) of SBM among the countries. The differences observed in the ingredient chemical profile of SBM between countries were not reflected in the growth and digestibility data of shrimp. These results highlight the importance of multiple variables influencing the biological value of soybean meals and that simplified generalizations such as country of origin, poorly define the quality of an ingredient. [ABSTRACT FROM AUTHOR]

A 20-d experiment was conducted to test the hypothesis that phytase increases nutrient digestibility, bone ash, and growth performance of pigs fed diets containing 0.23%, 0.29%, or 0.35% phytate-bound P. Within each level of phytate, five diets were formulated to contain 0, 500, 1,000, 2,000, or 4,000 phytase units (FTU)/kg of a novel phytase (PhyG). Three reference diets were formulated by adding a commercial Buttiauxella phytase (PhyB) at 1,000 FTU/kg to diets containing 0.23%, 0.29%, or 0.35% phytate-bound P. A randomized complete block design with 144 individually housed pigs (12.70 ± 4.01 kg), 18 diets, and 8 replicate pigs per diet was used. Pigs were adapted to diets for 15 d followed by 4 d of fecal collection. Femurs were collected on the last day of the experiment. Results indicated that diets containing 0.35% phytate-bound P had reduced (P < 0.01) digestibility of Ca, P, Mg, and K compared with diets containing less phytate-bound P. Due to increased concentration of total P in diets with high phytate, apparent total tract digestible P and bone ash were increased by PhyG to a greater extent in diets with 0.29% or 0.35% phytate-bound P than in diets with 0.23% phytate-bound P (interaction, P < 0.05). At 1,000 FTU/kg, PhyG increased P digestibility and bone P more (P < 0.05) than PhyB. The PhyG increased (P < 0.01) pig growth performance, and pigs fed diets containing 0.35% or 0.29% phytate-bound P performed better (P < 0.01) than pigs fed the 0.23% phytate-bound P diets. In conclusion, the novel phytase (i.e., PhyG) is effective in increasing bone ash, mineral digestibility, and growth performance of pigs regardless of dietary phytate level. [ABSTRACT FROM AUTHOR]

An experiment was conducted to test the hypothesis that there are no differences among sources of sunflower co-products on the apparent total tract digestibility (ATTD) of P and Ca and on the standardized total tract digestibility (STTD) of P regardless of where the ingredients were produced. Six sources of sunflower meal (SFM) were obtained from the U.S. (2 sources), Ukraine (2 sources), Hungary, and Italy. A source of sunflower expellers (SFE) from the U.S. was also used. Seven diets were formulated by mixing each source of sunflower co-product with cornstarch; therefore, the sunflower co-product was the only source of P in these diets. Seven additional diets that were similar to the previous seven diets with the exception that 300 units per kg of microbial phytase were added were also formulated. A total of 112 barrows (initial body weight = 17.95 kg ± 1.37 kg) were allotted to the 14 diets using 4 blocks, 2 pigs per diet in each block, and a total of 8 replicate pigs per diet. Pigs were placed in individual metabolism crates to allow for the total collection of fecal materials for 4 days after 7 days of adaptation to the diets. Diets and dried fecal samples were analyzed for dry matter, Ca, and P. Data for Ca and P digestibility were analyzed in a randomized complete block design in a 7 × 2 factorial arrangement using the PROC MIXED function in SAS. Results indicated that diets containing phytase had greater (P < 0.01) ATTD of Ca and P and greater (P < 0.01) STTD of P than diets without phytase (Table 1). Digestibility of P was also greater in one of the sources of SFM from Ukraine compared with the other sources except for the SFM from Hungary (Table 2). Pigs fed the diet containing one of the sources of SFM from the U.S. had greater (P < 0.05) ATTD of Ca compared with pigs fed diets containing the other source of SFM from the U.S. or one of the Ukraine SFM sources. In conclusion, some variability in the ATTD and STTD of P and the ATTD Ca was observed among SFM of different origins, but the ATTD and STTD of P and ATTD of Ca in SFM and SFE were greater if microbial phytase was used. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to test the hypothesis that both drying temperature and drying time affect the standardized ileal digestibility (SID) of amino acids (AA) and metabolizable energy (ME) in corn fed to growing pigs. A single source of corn was divided into 11 batches that were dried using a "drying chamber" at 80°C for 1.5, 3.0, 24, or 48 h or at 130°C for 1.5, 3.0, 6.0, 9.0, 12, 24, or 48 h. Exp. 1 was designed to determine the concentrations of ME in the 11 batches of corn. Eleven diets based on each batch of corn were formulated. Growing barrows (n = 88; BW = 20.6 ± 1.2 kg) were allotted to the 11 diets in a randomized complete block design with 8 blocks of 11 pigs. Urine and fecal samples were collected for 4-days after 7-days of adaptation. Contrast statements were used to determine effects of temperature and drying time within temperature. Exp. 2 was designed to determine the SID of AA in the 11 batches of corn. An N-free diet and 11 diets that each contained one of the 11 batches of corn as the sole source of AA were formulated. All diets contained 0.40% chromic oxide as an indigestible marker. Twenty-four growing pigs (22.8 ± 5.1 kg) that had a T-cannula installed in the distal ileum were allotted to a replicated 12 × 4 Youden square with 12 diets and four 7-day periods in each square. Therefore, there were 8 replicate pigs per diet. Ileal digesta were collected on days 6 and 7 of each 7-days period. Data were analyzed as described for Exp. 1. Results indicated that ME (dry matter basis) was greater (P < 0.01) if corn was dried at 130°C than at 80°C (Table 1). The ME (dry-matter basis) increased (quadratic, P < 0.04) with drying time at 80°C, whereas it decreased at 130°C (quadratic, P < 0.05). The SID of AA did not differ between corn dried at 80°C and 130°C, except that the SID of Lys was less (P < 0.05) if corn was dried at 130°C than at 80°C. The SID of most AA decreased (linear or quadratic, P < 0.05) as time of drying increased at 130°C. In conclusion, the SID of AA and ME in corn are not reduced by extending the time of drying at 80°C. However, the digestibility of AA is reduced if corn is dried at 130°C and the longer the time of drying the more the SID of AA is reduced. Values for ME in corn are increased if corn is dried at 130°C rather than 80°C. [ABSTRACT FROM AUTHOR]

The objective was to test the hypothesis that addition of microbial phytase to corn increases net energy (NE) by group-housed growing pigs. Three diets were formulated. The positive control (PC) diet contained corn as the sole source of energy. The PC diet contained Ca and P at the requirements for pigs (NRC, 2012). The negative control (NC) diet was similar to the PC except that this diet contained 0.08% standardized total tract digestible P and 0.12% total Ca less than the PC diet. The third diet was similar to the NC diet with the exception that this diet contained 1,000 units of phytase per kg diet. Pigs were allowed ad libitum access to feed and water. Pigs (n = 24; initial body weight = 44.99 kg; SD = 2.09) were allotted to the 3 diets using a replicated 6 × 3 incomplete Latin square design with 6 chambers (i.e., 4 pigs/chamber) and 3 periods. Oxygen consumption and CO2 and CH4 production were measured during fed and fasting states and fecal and urine samples were quantitatively collected. The statistical model included diet as the fixed effect and chamber and period as random effects. Result indicated that the apparent total tract digestibility (ATTD) of dry matter and gross energy, energy excretion in feces, urine, and heat, and NE did not differ among the 3 diets (Table 1). However, concentrations of digestible energy (DE) and metabolizable energy (ME) in diets and in corn were less (P < 0.05) in the PC diet compared with the NC diet without phytase, but no difference was observed between the PC diet and the NC diet with phytase or between the 2 NC diets. The ratio between NE and ME was not different among diets, but ME to DE was increased (P < 0.05) by supplementation of phytase to the NC diet. In conclusion, concentrations of DE and ME in corn are less if more feed phosphate and limestone are used in diets. However, concentrations of NE were not affected by supplemental phytase or Ca and P levels, even though ME to NE was increased by supplemental phytase. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to test the hypothesis that the digestibility of gross energy (GE) and nutrients, and concentrations of digestible energy (DE) and metabolizable energy (ME) in two sources of distillers dried grains with solubles (DDGS) are not different despite different concentrations of fat in the two sources. Cold-fermented DDGS (6.82% fat) and a conventional DDGS (9.54% fat) were used. In experiment 1, 12 growing barrows (initial body weight = 55.2 ± 3.6 kg) that had a T-cannula installed in the distal ileum were allotted to one of three diets and two periods. Two diets contained either cold-fermented or conventional DDGS as the sole source of crude protein (CP) and amino acids (AA). The third diet was an N-free diet that was used to determine the basal endogenous losses of AA from the pigs. Each experimental period lasted 7 d and ileal digesta were collected on days 6 and 7 of each period. Results demonstrated that values for the standardized ileal digestibility (SID) of CP and most AA were greater (P < 0.05) or tended to be greater (P < 0.10) in cold-fermented than in conventional DDGS. In experiment 2, 24 barrows (initial body weight = 17.3 ± 1.3 kg) were randomly allotted to three diets with 8 replicate pigs per diet. A corn-based basal diet and two diets containing corn and either cold-fermented DDGS or conventional DDGS were formulated. Pigs were housed individually in metabolism crates and feces and urine were collected separately for 5 d after 7 d of adaptation. The apparent total tract digestibility (ATTD) of neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid-hydrolyzed ether extract (AEE) was greater (P < 0.01) in conventional DDGS than in cold-fermented DDGS, but there was no difference in ATTD of GE between the two sources of DDGS. However, conventional DDGS contained more (P < 0.001) DE and ME than cold-fermented DDGS because of greater GE. In conclusion, the SID of AA was greater in cold-fermented DDGS than in the conventional DDGS that was evaluated in this experiment, but the ATTD of NDF, ADF, and AEE, and ME were greater in conventional DDGS than in cold-fermented DDGS. [ABSTRACT FROM AUTHOR]

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

An experiment was conducted to test the hypothesis that meat products have digestible indispensable amino acid scores (DIAAS) >100 and that various processing methods will increase standardised ileal digestibility (SID) of amino acids (AA) and DIAAS. Nine ileal-cannulated gilts were randomly allotted to a 9 × 8 Youden square design with nine diets and eight 7-d periods. Values for SID of AA and DIAAS for two reference patterns were calculated for salami, bologna, beef jerky, raw ground beef, cooked ground beef and ribeye roast heated to 56, 64 or 72°C. The SID of most AA was not different among salami, bologna, beef jerky and cooked ground beef, but was less (P < 0·05) than the values for raw ground beef. The SID of AA for 56°C ribeye roast was not different from the values for raw ground beef and 72°C ribeye roast, but greater (P < 0·05) than those for 64°C ribeye roast. For older children, adolescents and adults, the DIAAS for all proteins, except cooked ground beef, were >100 and bologna and 64°C ribeye roast had the greatest (P < 0·05) DIAAS. The limiting AA for this age group were sulphur AA (beef jerky), leucine (bologna, raw ground beef and cooked ground beef) and valine (salami and the three ribeye roasts). In conclusion, meat products generally provide high-quality protein with DIAAS >100 regardless of processing. However, overcooking meat may reduce AA digestibility and DIAAS. [ABSTRACT FROM AUTHOR]

Background: Raw meat contains all indispensable amino acids (IAAs), but before human consumption, meat usually undergoes some degree of processing. Processing affects the 3-dimensional structure of proteins, which may affect amino acid (AA) digestibility and, therefore, overall protein quality.Objectives: The experiment aimed at determining digestible indispensable amino acid scores (DIAAS) for pork products, and to test the hypothesis that processing increases DIAAS.Methods: Ten ileal cannulated gilts (body weight: 26.63 ± 1.62 kg) were randomly allotted to a 10 × 10 Latin square design with ten 7-d periods. Ileal digesta were collected for 9 h on days 6 and 7 of each period. Nine diets contained a single pork product (i.e., raw belly, smoked bacon, smoked-cooked bacon, non-cured ham, alternatively cured ham, conventionally cured ham, and loins heated to 63°C, 68°C, or 72°C) as the sole source of AAs. A nitrogen-free diet was formulated to determine basal endogenous losses of AAs, which enabled calculation of standardized ileal digestibility (SID) of AAs. DIAAS were subsequently calculated according to the FAO.Results: All pork products had DIAAS >100 (as-is basis). Loin heated to 63°C had the greatest (P < 0.05) DIAAS for children 6 mo to 3 y and smoked-cooked bacon had the greatest (P < 0.05) DIAAS for children older than 3 y, adolescents, and adults. Raw belly, smoked bacon, and loins heated to 68°C and 72°C had a reduced (P < 0.05) DIAAS for both reference patterns compared with other proteins. Alternatively cured ham had greater (P < 0.05) DIAAS when compared with non-cured ham and conventionally cured ham.Conclusions: Bacon, ham, and loin are excellent proteins with DIAAS >100, and processing may sometimes, but not always, increase DIAAS. [ABSTRACT FROM AUTHOR]

Three experiments were conducted to test the hypothesis that the standardized ileal digestibility (SID) of AA, concentrations of DE and ME, and the standardized total tract digestibility (STTD) of P in a source of torula yeast are not different from values obtained in Menhaden fish meal. In experiment 1, six weanling barrows (initial BW: 11.7 ± 0.4 kg) were prepared with a T-cannula in the distal ileum and allotted to a replicated 3 × 3 Latin square design with 3 diets and 3 periods. In each period, there were 5 d of adaptation and 2 d of collection. Two cornstarch-based diets using the torula yeast or fish meal as the sole source of AA and a N-free diet were formulated. The SID of CP and all AA was greater (P < 0.05) in torula yeast than in fish meal. In experiment 2, 24 weanling barrows (initial BW: 14.4 ± 1.1 kg) were individually housed in metabolism crates and allotted to a corn-based diet or 2 diets based on a mixture of corn and torula yeast or corn and fish meal. Feces and urine samples were collected for 4 d following a 5-d adaptation period. There were 8 replicate pigs per diet and fecal and urine materials were collected. Results of this experiment indicated that there were no differences in the concentration of DE and ME (DM basis) between torula yeast and fish meal. In experiment 3, a total of 32 weanling barrows (initial BW: 11.9 ± 1.1 kg) were allotted to 4 diets and 8 replicate pigs per diet. Pigs were placed in individual metabolism crates. The torula yeast or fish meal were used in 2 diets containing either 0 or 500 units of microbial phytase. Feces samples were collected as described for experiment 2. The STTD of P in torula yeast was greater (P < 0.05) than in fish meal, but regardless of ingredient, there was no effect of the inclusion of phytase in the diets. In conclusion, the SID of AA and the STTD of P in torula yeast is greater than in fish meal, but values for the concentration of DE and ME in torula yeast are not different from those in fish meal. Therefore, the torula yeast that was used in the present experiments may be included at the expense of fish meal in diets fed to weanling pigs if the concentration of standardized ileal digestible AA is considered in the formulation. [ABSTRACT FROM AUTHOR]

Due to the variations in nutrient quality of soybean meal (SBM) that is a result of differences in production location and processing specifications, a study was conducted to determine the fluctuations in apparent digestibility coefficients of differently sourced SBM fed to Pacific white shrimps (Litopenaeus vannamei). Twenty‐four SBM‐based diets were formulated by mixing a basal diet and test ingredients on a dry matter basis (70:30 ratio), while 1% chromic oxide was used as the inert marker. The digestibility trial was carried out in a semi‐closed recirculation system with six replicate groups per treatment (mean shrimp weight of 10.2 g). Significant differences were observed for apparent dry matter, energy and protein digestibility coefficients (p < .05 was considered significant) among 24 sources of SBM and digestibility values ranged from 45% to 90%, 56% to 93% and 87% to 98%, respectively. Based on multivariate analysis, acid detergent fibre, neutral detergent fibre, lignin, raffinose and trypsin inhibitor were screened as the key chemical characteristics in SBM that influenced digestibility of nutrients in Pacific white shrimps. Variations in growth performances of shrimp were in line with the variations in apparent digestibility coefficients of SBM verifying the importance of digestibility data in shrimp feed formulations. [ABSTRACT FROM AUTHOR]

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

An experiment was conducted to determine the standardized ileal digestibility (SID) of CP and AA in solvent extracted canola meal (CM) fed to gestating and lactating sows without or with a multi-enzyme complex. Eight sows cannulated on day 40 of gestation were randomly assigned to 1 of 4 dietary treatments in a replicated 4 × 4 Latin square design. The 4 diets included 2 cornstarch-based diets with 31.3% CM as the only source of AA, without or with a multi-enzyme complex, a casein-cornstarch diet to determine ileal endogenous AA losses, and a phosphorus-free diet (phosphorus digestibility data reported elsewhere). All diets contained 0.3% titanium dioxide. Gestating sows were fed 3.0 kg/d of the respective experimental diets, whereas, during lactation, sows had ad libitum access to experimental diets. Ileal digesta samples were collected in midgestation, late gestation, and lactation. In each period, after 6-d acclimation to the experimental diets, on days 7 and 8, ileal digesta samples were collected continuously for 12 h. Results indicated that sows in lactation had greater apparent ileal digestibility (AID) of CP and all AA (P < 0.05) compared with sows in gestation. Enzyme supplementation improved (P < 0.05) the AID of histidine, lysine, methionine, valine, and alanine, and a tendency (P < 0.10) for improvement in AID was observed for arginine, isoleucine, tryptophan, and cysteine during lactation, but not during gestation. However, the SID of most AA was not affected by collection phase, but enzyme supplementation improved (P < 0.05) the SID of arginine, histidine, lysine, methionine, and valine during lactation. The SID of indispensable AA in CM fed to gestating and lactating sows were as follows: arginine, 89.2 and 91.3%; histidine, 93.1 and 94.0%; isoleucine, 85.9 and 87.0%; leucine, 89.2 and 89.2%; lysine, 87.0 and 87.7%; methionine, 92.2 and 93.2%; phenylalanine, 89.2 and 87.8%; threonine, 84.3 and 82.7%; tryptophan, 88.1 and 91.5%; valine, 85.9 and 84.3%. In conclusion, the SID of AA in CM fed to lactating sows may be improved if a mixture of carbohydrases is included in the diet, but under the conditions of this experiment, the carbohydrase mixture did not affect SID of AA in CM fed to gestating sows in midgestation or late gestation. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

An experiment was conducted to determine the apparent total tract digestibility (ATTD) and the standardized total tract digestibility (STTD) of P in three varieties of hybrid rye and in one source of barley, wheat, corn, and sorghum. The STTD of P in each cereal grain was determined both without and with addition of microbial phytase. In total, 112 growing barrows (13.7 ± 1.3 kg initial BW) were allotted to a randomized complete block design with four blocks of 28 pigs. Pigs were randomly allotted to 14 diets with two replicate pigs per diet in each block, resulting in a total of eight replicate pigs per diet for the four blocks. Each diet contained one of the cereal grains as the sole source of P. There were two diets with each cereal grain with one diet containing no microbial phytase and the other diet containing 1,000 units of microbial phytase per kilogram of diet. In each period, fecal output was collected for 5 d following a 5-d adaptation period according to the marker-to-marker procedure. Among the diets that did not include microbial phytase, one hybrid of rye had greater (P < 0.05) STTD of P than wheat, corn, and sorghum, which is likely a result of the greater intrinsic phytase activity in rye than in the other cereal grains. Without microbial phytase, there was no difference in the STTD of P in the three hybrids of rye and barley. Among the diets containing microbial phytase, there was no difference in STTD of P among the three hybrids of rye, barley, and corn. The STTD of P in the three hybrids of rye with microbial phytase was 61.9%, 70.8%, and 63.0%, respectively. Overall, microbial phytase improved (P < 0.05) the STTD of P in all cereal grains, although the magnitude of the increase in STTD of P differed among the grains. [ABSTRACT FROM AUTHOR]

The objective was to test the hypothesis that the standardized total tract digestibility (STTD) of Ca and the response to microbial phytase on STTD of Ca and apparent total tract digestibility (ATTD) of P in diets fed to gestating sows are constant throughout gestation. The second objective was to test the hypothesis that retention of Ca and P does not change during gestation. Thirty-six gestating sows (parity = 3.3 ± 1.5; d of gestation = 7 d) were allotted to 4 diets. Two diets containing 0 or 500 units of microbial phytase per kilogram were based on corn, potato protein concentrate, and calcium carbonate. Two Ca-free diets were also formulated without or with microbial phytase to estimate basal endogenous loss of Ca. Daily feed allowance was 1.5 times the maintenance energy requirement. Sows were housed individually in gestation stalls and fed a common gestation diet, but they were moved to metabolism crates from days 7 to 20 (early gestation), days 49 to 62 (midgestation), and again from days 91 to 104 (late gestation). When sows were in metabolism crates, they were fed experimental diets and feces and urine were quantitatively collected for 4 d after 4 d of adaptation. Results indicated that outcomes were not influenced by the interaction between period of gestation and dietary phytase. The basal endogenous loss of Ca was greater (P < 0.05) by sows in early gestation than by sows in mid- or late-gestation, but supplementation of microbial phytase to the Ca-free diet decreased (P < 0.01) the basal endogenous loss of Ca and tended (P = 0.099) to increase ATTD of P. Supplementation of microbial phytase did not affect ATTD of DM, STTD of Ca, Ca retention, ATTD of P, or P retention in sows fed the calcium carbonate-containing diet. The ATTD of DM was not affected by period of gestation, but the ATTD of Ca, the ATTD of P, and the retention of Ca were least (P < 0.05) in midgestation, followed by early and late gestation, respectively, and the STTD of Ca in midgestation was also reduced (P < 0.05) compared with sows in early or late gestation. Phosphorus retention was greater (P < 0.05) in late gestation than in the earlier periods. In conclusion, Ca retention was less negative and ATTD of P tended to increase with supplementation of microbial phytase to the Ca-free diet regardless of gestation period. The basal endogenous loss, STTD of Ca, ATTD of P, and retention of Ca and P in gestating sows change during gestation with the greatest digestibility values observed in late gestation. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to test the hypothesis that the apparent ileal digestibility (AID) of AA, CP, and GE, the apparent total tract digestibility (ATTD) of CP and GE, and the apparent hindgut digestibility of CP and GE by growing pigs may be improved by supplementing diets with two direct-fed microbials (DFM) containing different Bacillus strains. Twenty-four growing barrows (initial BW: 22.69 ± 1.48 kg) that had a T-cannula installed in the distal ileum were individually housed and randomly allotted to a three diet, three period design with 24 pigs and three 21-d periods. There were eight pigs per diet in each period for a total of 24 observations per diet. Three diets that were based on corn, soybean meal, and distillers dried grains with solubles were formulated. The control diet contained no DFM, but two additional diets contained two different Bacillus strains (Bacillus amyloliquefaciens or Bacillus subtilis). Feed was provided in mash form in two daily meals at 0800 and 1600 hours. The initial 12 d of each period was the adaptation period to the diet. Fecal and urine samples were collected from days 13 to 18, and ileal digesta were collected for 8 h on days 20 and 21. Results indicated that there were no differences among diets in ATTD of CP, but the AID of CP was reduced (P < 0.05) for the B. subtilis diet compared with control and B. amyloliquefaciens diets. Therefore, the apparent hindgut digestibility of CP was greater (P < 0.005) in pigs fed the B. subtilis diet compared with the other diets. The AID of total indispensable, total dispensable, and total AA was greater (P < 0.05) in the B. amyloliquefaciens diet compared with the control diet. There were no differences among diets in ATTD of GE, but the AID of GE was greater for the B. amyloliquefaciens diet than for the control and the B. subtilis diets (P < 0.001). Therefore, the apparent hindgut digestibility of GE was less (P < 0.05) in the B. amyloliquefaciens diet compared with the other diets. The DE (DM basis) for the B. subtilis diet was greater (P < 0.05) compared with the control and the B. amyloliquefaciens diets. In conclusion, supplementation of Bacillus spp. to diets fed to growing pigs may increase the AID of AA and GE, but there appears to be differences among strains of Bacillus spp. in their impact on AA and energy digestibility. [ABSTRACT FROM AUTHOR]

An experiment was conducted to test the hypothesis that microbial xylanases may contribute to the degradation of fiber in wheat and wheat-based diets and in corn and corn-based diets along the intestinal tract of pigs. Twenty-four growing barrows (initial BW: 28.51 ± 1.86 kg) were prepared with a T-cannula in the proximal duodenum and another T-cannula in the distal ileum and allotted to a replicated 12 × 4 Youden square design with 12 diets and four 18-d periods. Two diets based on corn and soybean meal (SBM) or corn, SBM, and 30% distillers dried grains with solubles (DDGS) were formulated and two diets based on wheat and SBM or wheat, SBM, and 30% wheat middlings were also formulated. The four diets were formulated without microbial xylanase, or with one of two microbial xylanases (xylanase A or xylanase B) for a total of 12 diets. Feces and urine were collected on days 8 to 13, ileal digesta were collected on days 15 and 16, and duodenal digesta were collected on days 17 and 18 of each period. The apparent duodenal digestibility (ADD), apparent ileal digestibility (AID), and apparent total tract digestibility (ATTD) of GE, nutrients, and dietary fiber were calculated. Results indicated that the AID of GE in corn-SBM or wheat-SBM diets was greater (P < 0.05) than in the corn-SBM-DDGS and wheat-SBM-wheat middlings diets, but no difference was observed for the AID of dietary fiber between wheat-SBM and wheat-SBM-wheat middlings diets. The ATTD of dietary fiber was also greater (P < 0.05) in corn-SBM and wheat-SBM diets compared with corn-SBM-DDGS and wheat-SBM-wheat middlings diets, which indicates that the concentration of dietary fiber may influence the degree of fermentation of fiber. Inclusion of xylanase A or B improved (P < 0.05) the ADD and the ATTD of dietary fiber in wheat-based diets, indicating activity of xylanase in the gastro-intestinal tract of pigs. Inclusion of xylanase A improved (P < 0.05) the concentration of DE and ME in wheat-SBM-wheat middlings diets and xylanase B improved (P < 0.05) the concentration of DE in wheat-based diets and improved (P < 0.05) the concentration of the ME in wheat-SBM diet. In conclusion, the xylanases used in this experiment improved the digestibility of dietary fiber in the stomach and hindgut and improved the energy status of pigs fed wheat-based diets, but not of pigs fed corn-based diets. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to test the hypothesis that corn source 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 sources (i.e., soft or hard endosperm) were procured, and sources were divided into two drying batches (i.e., 35 or 120 oC). Therefore, four corn sources were used. In experiment 1, ten 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 five diets and five periods giving ten replicates per diet. A nitrogen-free diet and four diets containing each source of corn as the only AA source were formulated. Data were analyzed in a 2 × 2 factorial arrangement of treatments using the MIXED procedure of SAS. The model included corn source, drying temperature, and the interaction between corn source and drying temperature. Results indicated that neither source nor drying temperature influenced the apparent ileal digestibility of starch in corn (Table 1), but the standardized ileal digestibility of most AA was less (P < 0.05) in corn dried at 120 oC compared with corn dried at 35 oC. In experiment 2, 40 pigs (20.82 ± 1.74 kg) were housed in metabolism crates and allotted to four diets with ten replicate pigs per diet. The four corn-based diets used in experiment 1 were also used in experiment 2. Feces and urine were collected using the marker-to-marker approach with 5-day adaptation and 4-day collection periods. Data were analyzed as explained for experiment 1. Results indicated that diets containing hard endosperm corn had greater (P < 0.05) ATTD of TDF compared with diets containing soft endosperm corn. The ATTD of GE and the concentration of metabolizable energy (ME) in hard endosperm corn were also greater (P < 0.05) compared with soft endosperm corn. Diets containing corn dried at 120 oC had greater (P < 0.05) ATTD of TDF compared with diets containing corn dried at 35 oC, but drying temperature did not influence ATTD of GE or ME. In conclusion, endosperm hardness did not influence the digestibility of AA and starch; however, drying corn at 120 oC resulted in reduced digestibility of AA. Hard endosperm corn had greater ATTD of GE and TDF, but drying temperature did not influence energy digestibility. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to determine the effect of increased microbial phytase on total tract digestibility of P in feed phosphates when fed to growing pigs. A source of monocalcium phosphate (MCP), monosodium phosphate (MSP), and magnesium phosphate (MgP) were procured. Three basal diets were formulated to contain 0, 500, and 4,000 units of microbial phytase (FTU) and no addition of feed phosphates. Nine phosphate-containing diets were formulated by adding each of the 3 feed phosphates and 3 levels of phytase. A P-free diet was formulated to determine the basal endogenous P loss. A total of 117 growing barrows (BW = 15.56 kg; SD = 1.68) were divided into 3 blocks of 39 pigs and allotted to the 13 diets for a total of 9 pigs per diet. During the experiment, pigs were housed individually in metabolism crates equipped with a slatted floor, a feeder, and a nipple drinker. Fecal samples were quantitatively collected for 4 days after 5 days of adaptation using the marker-to-marker approach. Fecal samples were dried and ground before analysis. Fecal samples, feed ingredients, feed phosphates, and diet samples were analyzed for P, Ca, and dry matter and the apparent total tract digestibility (ATTD) and standardized total tract digestibility (STTD) were calculated. The ATTD and STTD of P in the 3 feed phosphates were calculated using difference procedure. The statistical model included the level of phytase and the P source as the fixed effects and the random effects of period and replicate within period. Contrast statements were used to test for linear and quadratic effects of increasing phytase in diets and the model included diet as the fixed effect and period and replicate as the random effects. Pig was the experimental unit. Results indicated that the ATTD and STTD of P in all diets increased (P < 0.05) with the inclusion of 500 or 4,000 FTU, but the ATTD and STTD of P in feed phosphates were not affected by the inclusion of phytase (Table 1). 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) 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. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to test the hypothesis that the basal endogenous loss of P from pigs fed a diet containing blood plasma, casein, or potato protein concentrate is not different from that of pigs fed a diet containing gelatin. Pigs (n = 40; body weigh =: 19.34 kg) were housed in metabolism crates and were randomly allotted to four low-P diets containing 20% gelatin, 20% blood plasma, 18.5% casein, or 20% potato protein concentrate. With the exception of Ca and P, diets were formulated to meet the requirements for 11 to 25 kg pigs. Feces and urine samples were collected separately for 4 d following a 5-d adaptation period. Feces samples were dried, ground, and analyzed for Ca and P, and urine samples were also analyzed for Ca and P. Data were analyzed using a model that included diet as fixed effect and replicate as random effect. Results indicated that feed intake and fecal excretion of dry matter were greater (P < 0.05) in pigs fed diets containing blood plasma, casein, and potato protein concentrate compared with pigs fed the gelatin diet, with pigs fed potato protein concentrate having the greatest (P < 0.05) excretion (Table 1). The apparent total tract digestibility of dry matter was least (P < 0.001) in pigs fed the diet containing potato protein concentrate, but there were no differences among gelatin, blood plasma, and casein diets. No differences were observed in the standardized total tract digestibility of P among diets. Basal endogenous loss of P was not different between the gelatin and casein diets, but pigs fed diets containing blood plasma or potato protein concentrate had greater (P < 0.001) basal endogenous loss of P compared with pigs fed gelatin or casein diets. In conclusion, the basal endogenous loss of P was greater in diets containing blood plasma and potato protein concentrate compared with gelatin. However, casein could be an alternative to gelatin to estimate the basal endogenous loss of P because casein provides a greater amount of P compared with gelatin that compensates for the deficient level of P in gelatin, but does not affect values for the basal endogenous loss of P. [ABSTRACT FROM AUTHOR]

The objective was to test the hypothesis that digestible energy (DE), metabolizable energy (ME), standardized ileal digestibility (SID) of amino acids (AA), and standardized total tract digestibility (STTD) of P in soybean meal produced from a new variety of soybeans (Photoseed) are not different from conventional soybean meal (SBM-CV). In Exp. 1, thirty pigs (18.3 ± 1.3 kg) were randomly allotted to a corn diet or 2 diets containing corn and Photoseed or corn and SBM-CV. Pigs were housed in metabolism crates and feces and urine were collected for 4 days after 5 days of adaptation. Feces and urine were analyzed for gross energy and DE and ME were calculated for each ingredient. The statistical model included ingredient as fixed effect and replicate as random effect and pig was the experimental unit. Results indicated that DE and ME of Photoseed were not different from DE and ME in SBM-CV (Table 1). In Exp. 2, nine barrows (30.0 ± 1.5 kg) with a T-cannula in the distal ileum were allotted to a triplicated 3 × 3 Latin Square design with 3 diets and 3 periods in each square. An N-free diet and diets containing SBM-CV or Photoseed were used. Pigs were housed individually in fully slatted pens and ileal digesta were collected on d 6 and 7 of each period. Digesta samples were lyophilized, ground, and analyzed for AA, and SID of AA was calculated. The statistical model included diet as fixed effect and square, period, and pig as random effects, and pig was the experimental unit. Results indicated that the SID of Arg, Ile, and Lys were not different between the two ingredients (Table 2), but the SID of other indispensable AA were greater (P < 0.05) in SBM-CV than in Photoseed. In Exp. 3, forty-eight barrows (12.0 ± 1.6 kg) were allotted to 6 diets with 8 pigs per diet. The SBM-CV or Photoseed were included in diets with 3 levels of microbial phytase (0, 500, or 1,000 units/kg). Pigs were housed in metabolism crates and feces were collected quantitatively for 4 days after 5 days of adaptation. Fecal samples were dried and analyzed for P and the STTD of P was calculated. The statistical model included ingredient, phytase, and the interaction between ingredient and phytase as fixed effects and replicate as the random effect. The pig was the experimental unit. Results indicated that inclusion of phytase in the diets increased (P < 0.05) the STTD of P, but STTD of P in Photoseed was not different from the STTD in SBM-CV (Table 3). In conclusion, no differences in DE and ME, STTD of P, and SID of some indispensable AA between Photoseed and SBM-CV were observed. [ABSTRACT FROM AUTHOR]

An experiment was conducted to test the hypothesis that inclusion of increasing concentrations of an Escherichia coli phytase to a corn-soybean meal (SBM) diet results in improved digestibility of DM, GE, CP, NDF, ADF, macrominerals, microminerals, and AA. Twenty-four growing barrows (initial BW: 37.0 ± 1.4 kg) were equipped with a T-cannula in the distal ileum and placed individually in metabolism crates, and allotted to a 2-period switch-back design with 6 diets and 4 replicate pigs per diet in each period. The positive control diet was a corn-SBM diet that contained limestone and dicalcium phosphate to meet the requirement for standardized total tract digestible (STTD) P and Ca (0.31% STTD P and 0.70% Ca). A negative control diet that was similar to the positive control diet, with the exception that no dicalcium phosphate was used, was also formulated, and this diet contained 0.16% STTD P and 0.43% Ca. Four additional diets were formulated by adding 500, 1,000, 2,000, or 4,000 units of microbial phytase (FTU) to the negative control diet. Each period lasted 14 d. Fecal and urine samples were collected from the feed provided from days 6 to 11 of each period following 5 d of adaptation to the diets. Ileal digesta were collected for 8 h on days 13 and 14. Results indicated that addition of the E. coli phytase to the negative control diet tended to quadratically improve the apparent ileal digestibility of Phe (P = 0.086) and Asp (P = 0.054), and linearly increased (P < 0.05) the apparent total tract digestibility (ATTD) of ADF, K, and Fe. Microbial phytase also quadratically increased (P < 0.05) the ATTD of NDF and Mg, and linearly and quadratically increased (P < 0.05) the ATTD and retention of Ca and P. However, no effects of the phytase on ATTD of GE or the concentration of DE were observed. In conclusion, the increased absorption of several minerals including Ca, P, K, Mg, and Fe that was observed as increasing concentrations of an E. coli phytase was added to a corn-SBM meal diet indicates that the dietary provision of these minerals may be reduced if phytase is fed. [ABSTRACT FROM AUTHOR]

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, soybeanmeal, 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. [ABSTRACT FROM AUTHOR]

The objective of this research was to compare values for digestible energy (DE) and metabolisable energy (ME) and apparent total tract digestibility (ATTD) of nutrients in 11 diets fed to both growing pigs and gestating sows. Three diets were based on corn, wheat or sorghum and eight diets were based on a combination of corn and soybean meal, canola meal, conventional distillers’ dried grains with solubles, low-fat distillers’ dried grains with solubles, corn germ meal, corn bran, wheat middlings or soybean hulls. A total of 88 gestating sows (252 ± 24.2 kg BW; parity two to six) and 88 growing barrows (40 ± 4.7 kg BW) were used and randomly allotted to the 11 diets with eight replicate sows or pigs per diet. Faecal and urine samples were collected for 4 d following a 19 d adaptation period. The DE, ME and ATTD of gross energy (GE), acid detergent fibre (ADF), neutral detergent fibre (NDF) and crude protein (CP) in the 11 diets were calculated. Gestating sows had greater (p < 0.05) ATTD of GE and CP and DE values for all diets compared with growing pigs. Gestating sows also had greater (p < 0.05) ME values than growing pigs for the three grain diets and the diets containing wheat middlings and soybean hulls. No differences were observed in ATTD of ADF and NDF between gestating sows and growing pigs for any of the diets, except that gestating sows had greater (p < 0.05) ATTD of NDF than growing pigs when they were fed the four protein diets. The ATTD of GE and CP and DE values in gestating sows may be predicted by using equations generated from the values of ATTD of GE and CP and DE values obtained in growing pigs. Results of this research indicate that ATTD values of CP and GE obtained in gestating sows are greater than the values obtained in growing pigs, but values for ATTD of ADF obtained in growing pigs are not different from values in gestating sows. [ABSTRACT FROM PUBLISHER]

To determine values for the digestible indispensable amino acid score (DIAAS), it is recommended that ileal amino acid (AA) digestibility values obtained in growing pigs are used to characterise protein quality in different foods. Therefore, an experiment was conducted to determine the standardised ileal digestibility (SID) of AA in eight cereal grains (yellow dent maize, Nutridense maize, dehulled barley, dehulled oats, polished white rice, rye, sorghum and wheat) fed to pigs, where SID values in pigs can be used to calculate approximate DIAAS values in humans. In the present experiment, twenty-four barrows with a T-cannula inserted in the distal ileum were allotted to eight diets and fed for three periods to give a total of nine replicate pigs per diet. Each period lasted 14 d, and ileal digesta samples were collected on days 13 and 14. Among the SID values obtained for all cereal grains, values for total indispensable AA were greatest (P< 0·05) in rice and lowest (P< 0·05) in rye and sorghum. The concentrations of SID indispensable AA in rice were less (P< 0·05) than in dehulled oats, but greater (P< 0·05) than in the other cereal grains, and the concentrations of SID indispensable AA in Nutridense maize were greater (P< 0·05) than in yellow dent maize and sorghum, but less (P< 0·05) than in the other cereal grains, except rye. In conclusion, results indicate that to meet dietary requirements for AA in humans, diets based on yellow dent maize or sorghum require more AA supplementation than diets based on other cereal grains. [ABSTRACT FROM PUBLISHER]

An experiment was conducted to test the hypothesis that the standardised digestibility of Ca in calcium carbonate andLithothamniumcalcareumCa is not different regardless of the level of dietary Ca, and that phytic acid affects the digestibility of Ca in these two ingredients to the same degree. The objectives were to determine where in the intestinal tract Ca absorption takes place and if there are measurable quantities of basal endogenous Ca fluxes in the stomach, small intestine or large intestine. Diets contained calcium carbonate orL. calcareumCa as the sole source of Ca, 0% or 1% phytic acid and 0.4% or 0.8% Ca. A Ca-free diet was also formulated and used to measure endogenous fluxes and losses of Ca. Nine growing pigs (initial body weight 23.8 ± 1.3 kg) were cannulated in the duodenum and in the distal ileum, and faecal, ileal and duodenal samples were collected. Duodenal endogenous fluxes of Ca were greater (p < 0.05) than ileal endogenous fluxes and total tract endogenous losses of Ca, but ileal endogenous fluxes were less (p < 0.05) than total tract endogenous losses. Standardised digestibility of Ca was not affected by the level of phytic acid, but decreased (p < 0.05) as Ca level increased inL. calcareumCa diets, but that was not the case if calcium carbonate was the source of Ca (interaction,p < 0.05). The standardised duodenal digestibility (SDD), standardised ileal digestibility (SID) and standardised total tract digestibility (STTD) of Ca were not different if calcium carbonate was the source of dietary Ca. However, the STTD of Ca inL. calcareumCa was greater (p < 0.05) than the SID and SDD of Ca. The SDD, SID and STTD of Ca in calcium carbonate were greater (p < 0.05) than those ofL. calcareumCa. In conclusion, under the conditions of this experiment, standardised digestibility of Ca is not affected by the level of phytic acid, but may be affected by dietary Ca level depending on the Ca source. Calcium from calcium carbonate is mostly absorbed before the duodenum, but Ca fromL. calcareumCa is mostly absorbed in the jejunum and ileum. [ABSTRACT FROM PUBLISHER]

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

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. [ABSTRACT FROM AUTHOR]

The objective was to test the hypothesis that standardized total tract digestibility (STTD) of Ca and Ca and P retention and the response to microbial phytase in diets fed to sows are constant throughout gestation. Thirty-six sows (parity = 3.3) were allotted to 4 diets on d 7 post-breeding. Two corn-based diets in which calcium carbonate was the sole source of Ca and 2 Ca-free diets were formulated without or with phytase (500 units per kg). Sows were housed individually in metabolism crates during early-gestation, mid-gestation, and late-gestation, and feces and urine were quantitatively collected. Data were analyzed by repeated measures using a model that included phytase, period of gestation, and the interaction between phytase and period as fixed effects, and block and replicate as random effects. Interactions between period and phytase were not observed. The basal endogenous loss (BEL) of Ca was greater (P < 0.05) in early-gestation than in mid- and late-gestation, but phytase reduced (P = 0.002) BEL of Ca and tended (P = 0.099) to increase apparent total tract digestibility (ATTD) of P in the Ca-free diet. Phytase did not affect ATTD of DM, STTD of Ca, ATTD of P, or Ca and P retention in sows fed the diet containing calcium carbonate (Table 1). The ATTD of DM was not affected by period, but Ca retention and ATTD of Ca and P were least (P < 0.05) in mid-gestation, followed by early- and late-gestation, and the STTD of Ca in mid-gestation was also reduced (P < 0.05) compared with early- or late-gestation. Phosphorus retention was greater (P < 0.05) in late-gestation than in the earlier periods. In conclusion, BEL of Ca, STTD of Ca, ATTD of P, and Ca and P retention in sows change throughout gestation regardless of use of phytase. http://www.conferenceharvester.com/ [ABSTRACT FROM AUTHOR]

The objective was to test the hypothesis that standardized total tract digestibility (STTD) of Ca and the response to microbial phytase is constant among different sources of calcium carbonate and different sources of dicalcium phosphate (DCP). In Exp. 1, 80 pigs (19.0 ± 1.9 kg) were placed in metabolism crates and randomly allotted to 10 diets. Four calcium carbonate-containing diets and a Ca-free diet were formulated without or with microbial phytase (500 units/kg diet). Feces were collected for 4 d after a 5 d adaptation period. Data were analyzed using a model that included calcium carbonate source, phytase, and the interaction between source and phytase as fixed effects and replicate as random effect. There were no interactions between phytase and source. The basal endogenous loss (BEL) of Ca from pigs fed phytase was less (P = 0.037) than from pigs fed no phytase. Values for STTD of Ca in calcium carbonate differed (P < 0.05) among the 4 sources, but increased (P < 0.05) if phytase was used (Table 1). In Exp. 2, 40 pigs (14.9 ± 1.3 kg) were allotted to a basal diet where all Ca was supplied by calcium carbonate, 3 diets containing calcium carbonate and DCP, and a Ca-free diet. Pigs were placed in metabolism crates and feces were collected as in Exp. 1. Data were analyzed using a model that included DCP-source as fixed effect and replicate as random effect. Results indicated that the STTD of Ca in DCP was not different among sources. In conclusion, use of microbial phytase reduces the BEL of Ca and increases Ca digestibility in calcium carbonate, but the STTD of Ca varies among sources of calcium carbonate. However, no difference in STTD of Ca among sources of DCP were observed. [ABSTRACT FROM AUTHOR]

An experiment was conducted to test the hypothesis that values for standardized ileal digestibility (SID) of amino acids (AA) in cereal grains and fiber rich ingredients obtained using the direct method are not different from values obtained using the difference method. Sixteen ileal-cannulated barrows (69.45 ± 5.01 kg) were allotted to an 8 diets × 4 period Youden square design. Each period consisted of 5 d of adaptation and 2 d of ileal digesta collection. Four diets were based on soybean meal (SBM), corn, wheat, or wheat middlings as the only AA-containing ingredients. Three additional diets were based on a mixture of SBM and corn, wheat, or wheat middlings and a N-free diet was also used. The SID of AA in the 4 diets containing SBM, corn, wheat, or wheat middlings as the sole source of AA were calculated using the direct method. The SID of AA in corn, wheat, and wheat middlings were also calculated by difference from the 3 diets containing SBM and corn, wheat, or wheat middlings by subtracting the contribution from SBM of each AA from the SID values for the mixed diet. Data were analyzed using a model that included the method of determination of AA digestibility as the fixed effect, and pig and period as random effects. There was no difference between the direct and the difference method for the SID of most AA in corn, wheat, and wheat middlings, although the SID of Trp was lower (P < 0.05) for the difference method than values derived by the direct method for both corn and wheat middlings (Table 1). Therefore, values for SID of AA in cereal grains or fiber-rich ingredients could be obtained using either the direct method or the difference method. [ABSTRACT FROM AUTHOR]

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

The hypothesis that the standardized ileal digestibility (SID) of AA, concentration of ME, and the standardized total tract digestibility (STTD) of P in an enhanced torula yeast (ETY; Arbiom, Raleigh, NC) are not different from values obtained in Menhaden fish meal (FM) was tested. In Exp. 1, 6 ileal cannulated barrows (11.7 ± 0.4 kg) were allotted to a replicated 3 × 3 Latin square with 3 diets (ETY, FM, and N-free) and 3 7-d periods. Ileal digesta were collected on d 6 and 7 of each period. Data were analyzed using the Proc Mixed with diet as main effect and pig as random effect. The SID of AA was greater (P < 0.05) in ETY than in FM (Table 1). In Exp. 2, 24 barrows (14.4 ± 1.1 kg) were individually housed in metabolism crates and allotted to a corn diet or diets based on corn and ETY or corn and FM. Feces and urine were collected for 5 d. Data were analyzed as in Exp. 1. No difference in ME between ETY (3,636 kcal/kg DM) and FM (3,611 kcal/kg DM) was observed. In Exp. 3, 32 barrows (11.9 ± 1.1 kg) were allotted to 4 diets in a 2 × 2 factorial with 2 ingredients (ETY and FM) and 0 or 500 units/kg of phytase. Housing and fecal sample collection was as in Exp. 2. Data were analyzed as in Exp. 1 with diet and phytase as main effects. Phytase did not influence STTD of P, but the STTD of P in the ETY (91%) was greater (P < 0.05) than in FM (68%). In conclusion, the SID of AA and the STTD of P in ETY is greater than in FM, but the ME in ETY is not different from FM. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to test the hypothesis that the concentration of Ca in diets fed to late gestating sows affects the apparent total tract digestibility (ATTD) and retention of Ca and P, serum concentrations of Ca and P, hormones, and blood biomarkers for bone formation and resorption. Thirty-six sows (average parity = 2.8) were housed in metabolism crates from day 91 to day 104 of gestation and fed 1 of 4 experimental diets containing 25, 50, 75, or 100% of the requirement for Ca. All diets met the requirement for P. The initial 5 d of each period were the adaptation period, which was followed by 4 d of quantitative collection of feces and urine. At the end of the collection period, a blood sample was collected from all sows. Results indicated that feed intake, weights of dried fecal and urine samples, and the ATTD of DM were not affected by dietary Ca, but ATTD of Ca increased (quadratic, P < 0.05) as Ca in diets increased. Urine Ca output was not affected by dietary Ca, but Ca retention increased (quadratic, P < 0.05) as Ca intake increased. Fecal P output increased (linear, P < 0.001) as dietary Ca increased, which resulted in a linear decrease (P < 0.001) in the ATTD of P. Urine P output also decreased (linear, P < 0.001) as dietary Ca increased, but P retention increased (linear, P < 0.05). Regressing the apparent total tract digestible Ca against dietary Ca intake resulted in a regression line with a slope of 0.33, indicating that true total tract digestibility of Ca in calcium carbonate was 33%. Serum concentrations of Ca and P and estrogen, calcitonin, and parathyroid hormone were not affected by dietary Ca. Serum concentration of carboxyterminal cross-linked telopeptide of type I collagen (CTX-I) decreased (linear, P < 0.05) as dietary Ca increased, which is a result of reduced bone resorption as dietary Ca increased. Serum bone-specific alkaline phosphatase tended to decrease (linear, P < 0.10) as Ca in diets increased, but the concentration of osteocalcin (OC) in serum was not affected by dietary Ca. The ratio between OC and CTX-I tended to increase (P < 0.10) as dietary Ca increased, which indicated that there was more bone formation than resorption in sows as dietary Ca increased. In conclusion, P digestibility in late gestating sows decreased, but retention of P increased, as dietary Ca increased from inadequate to adequate levels and blood biomarkers for bone resorption changed as Ca and P retention increased. [ABSTRACT FROM AUTHOR]

An experiment was conducted to 1) test the hypothesis that a minimum adaptation period to diets used in ileal amino acid (AA) digestibility experiments with pigs is needed and 2) to test the null-hypothesis that ileal digestibility and basal endogenous losses of AA are not affected by the indigestible marker used. Eight ileal-cannulated barrows with an initial BW of 58.1 ± 4.3 kg were randomly allotted to a 2-period crossover design with 2 diets and 4 pigs per diet in each period. A soybean meal-based diet and an N-free diet were prepared. Both diets contained 0.4% chromium oxide, 0.4% titanium dioxide, and 0.4% Celite (a source of acid insoluble ash; AIA). Pigs were provided feed in a daily amount of 3 times the maintenance requirement for metabolizable energy, and 2 equal meals were provided each day. Ileal digesta samples were collected from 0800 to 2000 h on each day during the two 9-d collection periods. There was no period by diet interactions observed. Marker concentrations in ileal digesta were analyzed separately for each day, and the point where the concentration of each marker was stabilized in the digesta was determined using a linear broken-line analysis. For pigs fed the soybean meal diet, the breakpoints for Cr, Ti, and AIA in ileal digesta were 2.70, 2.45, and 3.77 d, respectively. In pigs fed the N-free diet, the breakpoints for Cr, Ti, and AIA in ileal digesta were 2.52, 2.39, and 2.29 d, respectively. Based on the pooled data, the basal endogenous losses of most AA calculated using Cr as an indigestible marker were less (P < 0.05) than the values calculated using Ti, but greater (P < 0.05) compared with values calculated based on AIA. The standardized ileal digestibility of most AA in soybean meal calculated using Cr or Ti as a digestibility marker were greater (P < 0.05) than the digestibility values calculated using AIA. In conclusion, 3 d of adaptation is required before markers are stabilized in the ileal outflow if Cr or Ti is used as an indigestible marker and 4 d of adaptation is required if AIA is the marker. Values for AA digestibility calculated using Cr or Ti as the marker are not different, but greater compared with values calculated using AIA as the marker. [ABSTRACT FROM AUTHOR]

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