N-free Diet Research Articles

Metabolizable energy and digestible nutrient values of protease-supplemented field pea for broiler chicken.

A study was conducted to determine the effects of protease supplementation of field pea (in comparison with soybean meal; SBM) for broilers on apparent metabolizable energy (AMEn) and standardized ileal digestibility (SID) of amino acids (AA). One hundred and forty broiler chicks were divided into 35 groups of 4 birds/group and fed 5 diets in a completely randomized design (7 groups/diet) from 14 to 21 d of age. The diets were cornstarch-based containing SBM or field pea as the sole protein source without or with protease (ProSparity 250TM; CBS Bio Platforms, Calgary, AB, Canada) in 2 × 2 factorial arrangement, and N-free diet. Protease was added to diets to supply 6,250 U/kg. Digestibility of AA and N retention for feedstuffs were determined by the direct method, whereas digestibility and retention of energy for feedstuffs were determined by the difference from the N-free diet. On as fed basis, SBM and field pea contained 90.0 and 88.9 dry matter, 46.6 and 20.2 % crude protein, 2.88 and 1.47 % Lys, and 14.3 and 14.7 % non-starch polysaccharides, respectively. On as fed basis, the AMEn value for field pea was lower (P < 0.05) than that of SBM (2,006 vs. 2,414 kcal/kg). Also, the SID values of most indispensable AA in field pea were lower (P < 0.05) than those in SBM. Feedstuff (field pea vs. SBM) and protease did not interact on AMEn and SID of AA values. The supplemental protease increased (P < 0.05) AMEn values of the SBM and field by an average of 187 kcal/kg but decreased (P < 0.05) the SID values of all indispensable AA (except His) for the SBM and field, by an average of 2.7 percentage points. Results indicate that the protease product used in the current study marginally reduced the SID of AA for both SBM and field pea. However, the protease product can be beneficially included in diets based on SBM or field pea for broilers to enhance their AMEn values. The response to the protease on the AMEn was consistent regardless of the protein source in the diet, implying that the protease used in this study has similar positive impact on energy availability in both field pea and SBM.

Effects of Extrusion on the Available Energy and Nutrient Digestibility of Soybean Meal and Its Application in Weaned Piglets.

Experiments were conducted to investigate the effects of extrusion devices on the available energy and nutrient digestibility of soybean meal (SBM), and further to investigate the impact of different levels of extruded SBM on the growth performance and nutrient digestibility of weaned piglets. In Exp. 1, eighteen crossbreed growing pigs with an initial body weight (BW) of 32.6 ± 2.7 kg were randomly assigned to three treatments, including a corn basal diet, SBM, and extruded SBM diets. In addition, six cannulated pigs (initial BW, 22.3 ± 1.8 kg) were allocated across an 6 × 3 Youden square design. The experimental treatments included a N-free diet and three diets containing 40% of different SBM sources. The results indicated that extrusion reduced the anti-nutritional factors in soybean meal without affecting the digestibility of available energy and nutrients. In Exp. 2, 192 pigs (initial BW, 6.60 ± 0.54 kg) were allocated across four diets supplemented with 0%, 3%, 6%, and 9% extruded SBM. The four treatments were randomized and each comprised six replicate pens containing four boars and four gilts. The results showed that average daily feed intake (ADFI) decreased linearly with the increase in extruded SBM levels from d 0-14 (p < 0.05), and average daily gain (ADG) increased; ATTD was higher in the GE, DM, OM, and CP of piglets in the 9% extruded SBM group (p < 0.05). In conclusion, the extrusion treatment reduced ANFs in SBM, and adding 9% extruded SBM to the diet improved the growth performance of weaned piglets by increasing the digestibility of nutrients.

Standardized Ileal Digestibility of Amino Acids in Hybrid Rye Ground to Two Particle Sizes and Fed With or Without Multienzyme Supplement to Young Growing Pigs.

A newly developed hybrid rye with enhanced ergot resistance has potential as an alternative energy source for pigs. An experiment was conducted to evaluate the effects of particle size (PS) and multienzyme supplement (MES) on the apparent total tract digestibility (ATTD) of energy and nutrients and the standardized ileal digestibility (SID) of amino acids (AA) in hybrid rye fed to growing pigs. Bono and Gatano, two hybrid rye varieties, were ground to either a coarse (1111 and 1210 μm) or a fine (594 and 717 μm) PS using a hammer mill. Eighteen ileal-cannulated barrows (initial BW = 18.2 ± 1.0 kg) were randomly assigned to 1 of 9 dietary treatments in a replicated 9 × 3 incomplete Latin square design to give six observations per treatment. Among the nine experimental diets, eight featured two hybrid rye varieties (Bono or Gatano), either coarsely or finely ground, as the only source of AA with or without MES, while an N-free diet was used to estimate the endogenous losses of AA at the distal ileum. All diets contained titanium dioxide as an indigestible marker. Each period lasted 9 days, with the first 5 days being for adaptation followed by 2 days each for faecal and ileal digesta collection. Data were analysed using the MIXED procedure of SAS, with the final model having variety, PS, MES, their two-way interactions, and a three-way interaction. No interactions were noted except that the apparent ileal digestibility and SID of crude protein (CP) and most AA in Gatano had greater effects of MES than Bono (Variety × MES; p < 0.05). The ATTD of dry matter (DM), gross energy (GE) and CP were greater (p < 0.05) in Bono diets than in Gatano diets. Finely ground hybrid rye diets had higher (p < 0.05) ATTD of neutral detergent fibre assayed with a heat stable amylase and expressed inclusive of residual ash (NDF) and ether extract compared to coarsely ground hybrid rye diets. Dietary MES supplementation increased (p < 0.05) the ATTD of DM, GE, CP, NDF, acid detergent fibre expressed inclusive of residual ash, and ash in hybrid rye diets. In conclusion, the nutrients digestibility of hybrid rye can be affected by its variety. PS reduction improved the nutrient digestibility in hybrid rye, and MES supplementation improved the energy and AA digestibility in hybrid rye fed to growing pigs.

Energy Values and Standardized Ileal Digestibility of Amino Acids in Fermented Soybean Meal Fed to Growing Pigs.

This study aimed to evaluate the digestible energy (DE), metabolizable energy (ME), and standardized ileal digestibility (SID) of amino acids (AA) in fermented soybean meal (FSBM) fed to growing pigs. In experiment 1, twenty-two growing pigs (Duroc × Landrace × Yorkshire; 32.0 ± 4.2 kg BW) were fed one of 11 diets in a replicated 11 × 3 incomplete Latin square design to determine the DE and ME of FSBM. The diets included a corn-based diet and 10 experimental diets formulated by replacing the corn with 29.10% FSBM. In experiment 2, eleven growing pigs (Duroc × Landrace × Yorkshire; 24.3 ± 2.3 kg BW) were surgically equipped with a T-cannula and arranged in an 11 × 6 incomplete Latin square design with 11 diets and six periods. The diets included an N-free diet and 10 experimental diets containing 40% FSBM as the sole source of AA. The results showed that the contents of dry matter (DM), gross energy, crude protein, crude fiber, neutral detergent fiber, acid detergent fiber, calcium, and phosphorus averaged 91.83% (ranging from 89.24 to 94.55%), 18.44 MJ/kg (ranging from 18.00 to 18.95 MJ/kg), 50.63% (ranging from 50.00 to 51.81%), 4.51% (ranging from 3.41 to 5.40%), 9.17% (ranging from 7.02 to 10.30%), 6.38% (ranging from 4.97 to 7.45%), 0.32% (ranging from 0.29 to 0.34%), and 0.67% (ranging from 0.61 to 0.84%), respectively. The average DE and ME were 17.55 and 16.33 MJ/kg DM, respectively, with ranges of 15.72 to 18.80 MJ/kg DM and 14.30 to 17.72 MJ/kg DM, respectively. Significant differences were observed in the SID of essential AA (p < 0.05), except for Thr and Arg. The SID of Lys, Met, Trp, and Thr ranged from 68.13 to 83.27% (mean = 76.62%), 62.23 to 89.30% (mean = 75.25%), 72.30 to 90.29% (mean = 80.96%), and 74.17 to 84.41% (mean = 77.90%), respectively. These results indicate significant variability in chemical composition, energy content, and the SID of AA among the selected FSBM samples. The chemical composition of FSBM can be used to predict DE and ME values.

Determination and Prediction of Amino Acid Digestibility in Rapeseed Cake for Growing-Finishing Pigs.

The experiment was conducted to determine the apparent or standardized ileal digestibility (AID or SID) of crude protein (CP) and amino acids (AA) in 10 rapeseed cake samples fed to pigs, and to construct predictive models for the SID of CP and AA based on the chemical composition of rapeseed cakes. Twenty-two cannulated pigs (initial body weight: 39.8 ± 1.2 kg) were assigned to two 11 × 3 incomplete Latin square designs, including an N-free diet and 10 diets containing rapeseed cake. Each experimental period included 5 days of adaptation and 2 days of ileal digesta collection. Titanium dioxide (TiO2) was added at 0.3% to all the diets as an indigestible marker for calculating the ileal CP and AA digestibility. The coefficients of variation (CV) of the content of crude fat (EE), crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF), and total glucosinolates (TGS) in 10 samples of rapeseed cake were greater than 10%. The standardized ileal digestibility (SID) of crude protein (CP), lysine (Lys), methionine (Met), threonine (Thr), and tryptophan (Trp) in rapeseed cake was 73.34% (61.49 to 81.12%), 63.01% (41.41 to 73.10%), 69.47% (50.55 to 88.16%), 79.61% (74.41 to 87.58%), and 94.43% (91.34 to 97.20%), respectively. The best prediction equations for SIDCP, SIDLys, and SIDVal were as follows: SIDCP = 90.124 - 0.54NDF (R2 = 0.58), SIDLys = 100.107 - 1.229NDF (R2 = 0.94), and SIDVal = 151.012 - 2.990TGS (R2 = 0.57). Overall, great variation exists among the 10 rapeseed cakes, and the NDF, TGS, and heating temperature can be used as the key predictors for the SID of CP and AA.

PSVI-28 Interactive effects of different fiber and lipid sources on amino acid digestibility in growing pigs

Abstract A study was conducted to determine the effects of different fiber and lipid sources on the digestibility of amino acids (AA) in growing pigs. Five diets were fed in this study. The diets were corn-soybean meal-based diet with either soybean hulls (SBH) or sugar beet pulp (SBP) as fiber source and either soybean oil (SBO) or choice white grease (CWG) as lipid source in a 2 × 2 factorial arrangement; and a N-free diet. The diets were formulated to be similar in content of AA, calcium, available phosphorus, and total dietary fiber. The SBH and SBP were each included in their respective diets at 15%, whereas the SBO and CWG were each included in their respective diets at 4.5%. The 5 diets were fed to 10 ileal-cannulated pigs [5 barrows and 5 gilts; initial average body weight (BW) = 54.8 ± 5.6 kg)]in a 5 × 5 Latin square design to give 10 replicates per diet. On an as fed basis, SBH and SBP contained 11.3 and 8.8% crude protein, 66.1 and 49.8% total non-starch-polysaccharides (NSP), 54.3 and 29.5% insoluble NSP, and 11.8 and 20.3% soluble NSP, respectively. The SBO and CWG contained &amp;gt;98.5 and &amp;gt;98.5% crude fat, 14.7 and 35.6% saturated fatty acids, and 76.6 and 62.5% unsaturated fatty acids, respectively. Dietary fiber source and lipid sources did not interact on standardized ileal digestibility (SID) of AA. The SBH- and SBP-containing diets did not differ regarding SID of all AA except Met and Trp. Pigs fed SBP-containing diets had lower (P &amp;lt; 0.05) SID of Met and greater (P &amp;lt; 0.05) SID of Trp than those fed SBH-containing diets by 2.5 and 4.7%, respectively. The SBO- and CWG-containing diets did not differ regarding SID of all AA except Trp. The SID of Trp for SBO-containing diets was greater (P &amp;lt; 0.05) than that for CWG-containing diets by 2.6%. In conclusion, the lack of interaction between dietary fiber and lipid sources on the SID of AA implies that these two factors (fiber and lipid sources) may exert their effects on ileal digestibility of AA independently if the fiber and lipid sources are included in diets for growing pigs at same levels included in the diets fed in the current study. The dietary fiber source and dietary lipid source had limited effects on the digestibility of most AA, implying that replacement of one fiber source with one another fiber source or of one lipid source with another lipid source in diets for growing pigs may have limited effect on digestibility of AA if the fiber and lipid sources are included in diets for growing pigs at same levels included in the diets fed in the current study.

Extrusion can ameliorate negative effects of molecular structures of brewer's spent grain on energy contents and amino acid digestibility in growing pigs.

The objectives of this study were to investigate the effects of extrusion on the chemical compositions, surface structure, and molecular structure of brewer's spent grain (BSG), as well as to determine the digestible energy (DE), metabolizable energy (ME), apparent total tract digestibility (ATTD) of nutrients and energy, and amino acid (AA) digestibility of extruded BSG when fed to growing pigs. Firstly, we determined the changes in chemical compositions and molecular structure of both non-extruded and extruded BSG. In Exp. 1, eighteen growing pigs were fed three different diets including one corn-soybean meal basal diet and two experimental diets containing 20% BSG with or without extrusion. Feces and urine were collected to determine the ATTD of nutrients and energy, DE, and ME of extruded or non-extruded BSG. In Exp. 2, eighteen growing pigs were fed three different diets including 30% BSG with or without extrusion, and an N-free diet. Ileal digesta was collected through the slaughter method to determine the apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of AA of extruded or non-extruded BSG. The results showed that extrusion reduced the neutral detergent fiber, hemicellulose and cellulose contents in BSG, and increased the Arg, Asp, Glu, Ser, Tyr, total indispensable AA and total AA contents of BSG, altered the surface structure of BSG, increased the peak absorbance in amide I and amide II height, amide II and amide (I+II) area, α-helix height, decreased β-sheet height, and weakened band intensities in cellulosic compounds (CELC) area, structural carbohydrates (SCHO) area, carbohydrates area (CHO) peak 2 and 3 height, the area ratio of CELC: CHO and CELC: SCHO. Moreover, DE and ME values and ATTD of energy, dry matter, crude protein, acid detergent fiber, neutral detergent fiber, cellulose and hemicellulose increased (P < 0.05) when pigs were fed extruded BSG diets. The AID and SID of Arg, His, Lys, Val and Gly increased, whereas the AID and SID of Ile and Leu decreased when pigs were fed extrusion diets (P < 0.05). Our study found that the ATTD of nutrients and AA digestibility in pigs were positively correlated with the molecular structure of proteins, and negatively correlated with the molecular structure of carbohydrates (P < 0.05). These findings suggested that extrusion had the potential to improve the nutrient digestibility of BSG by altering its chemical compositions, surface structure, and molecular structure.

Standardized ileal amino acid digestibility and performance indices in pullets and laying hens fed expeller-pressed Canadian prairie soybean meal

Soybean meals (SBM) from different locations differ in their protein content, subsequently influencing their amino acid (AA) profile. In this study, standardized ileal digestibility (SID) of AA and growth or production performance were evaluated in pullets and hens fed SBM derived from soybean grown in Western Canada, primarily Manitoba (MB) labelled as A-, B- and C-SBM compared with that from Eastern Canada (Ontario, ON-SBM) and contained 38.3 ± 0.44, 38.6 ± 0.61, 39.4 ± 0.49, or 44.0 ± 0.87% CP, respectively. A N-free diet was used to determine basal ileal endogenous losses of AA. The study included the grower, developer, and layer phases (9-12, 13-16, and 44/59-64-wk old birds, respectively). Although a lower (P = 0.029) SID for cysteine was noted in the grower phase for the C-SBM compared with other SBM, the developer phase had higher (P < 0.05) SID for methionine, phenylalanine, cysteine (more by 4.4, 2.4 and 7.2% units, respectively) on average for SBM samples from MB compared with the ON-SBM. Regardless the source of the SBM, no difference in SID of AA was noted in the layer phase. Overall, in all phases the SID values of most AA in the SBM from MB were comparable with the ON-SBM, which may be linked to higher values of these AA per unit of protein content in the former source. In addition, the growth performance including feed intake, BW gain and feed conversion ratio in pullets, and egg production/quality in layers were similar between treatments. These findings show that the MB-SBM have a comparable feeding value with the ON-SBM, hence represent a suitable alternative protein source for poultry.

157 Effects of increasing dietary protein concentration on digestibility of amino acids by growing pigs

Abstract Two experiments were conducted to test the hypothesis that the standardized ileal digestibility (SID) of amino acids (AA) by growing pigs is not influenced by dietary protein concentration if all AA are supplied by soybean protein isolate (SPI) or casein. In Exp. 1, cannulated pigs [n = 12; average body weight (BW) = 39.22 kg; SD = 3.96] were allotted to a replicated 6 × 3 Youden square design with the 6 diets and 3 periods. Five diets were formulated to contain 7 to 35% SPI. An N-free diet was also used. In Exp. 2, cannulated pigs (n = 24 average BW = 23.12 kg; SD = 2.89) were allotted a quadruplicated 6 × 2 Youden square design with the 6 diets and 2 periods. Five diets were formulated to contain 6.75 to 33.75% casein. An N-free diet was also used. Ileal digesta were collected and analyzed for dry matter (DM), Cr, and AA. The statistical models included diet as a fixed variable and square, animal, and period as random effects. Polynomial contrasts were used to test linear and quadratic effects of increasing dietary protein. Results from Exp. 1 indicated that the apparent ileal digestibility (AID) of DM linearly (P = 0.001) decreased and the AID of all AA quadratically (P &amp;lt; 0.05) increased as the inclusion of SPI increased in the diets (Table 1). The SID of His and Trp was not affected by the inclusion of SPI in the diets. However, the SID of Arg, Leu, Lys, Phe, Thr, and Val linearly (P &amp;lt; 0.05) decreased, and the SID of Ile and Met tended to linearly (P &amp;lt; 0.10) decrease as the inclusion of SPI in the diets increased. Results from Exp. 2 indicated that the AID of DM tended to linearly decrease (P = 0.089) as the inclusion of casein increased in the diets (Table 2). The AID of most AA increased quadratically (P &amp;lt; 0.01) and the AID of Trp tended to increase (quadratic, P = 0.068) with increasing inclusion rate of casein. The SID of most AA was independent of casein levels. In conclusion, the anti-nutritional factors may have been increased in the diets as the inclusion of SPI increased and thus resulted in reduced SID values. However, the SID values were not influenced by increasing dietary protein if all AA were supplied by casein that does not contain anti-nutritional factors. Therefore, it is concluded that pigs have the capacity to absorb peptides and AA with the same efficiency if the protein concentration is 30% as if it is 6%. Dietary protein concentration itself, therefore, is not likely to limit AA absorption. However, even small amounts of anti-nutritional factors appear to negatively impact the SID of AA.

PSII-17 Effect of protease supplementation on amino acids digestibility of soybean meal fed to growing pigs of different ages

Abstract Protease supplementation can increase amino acids (AA) availability; however, the effectiveness of protease in swine diets varies and has been associated with the type and dose of protease, dietary ingredients, and potentially animal age. This study investigated the interactive effect of protease inclusion level and pig age on standardized ileal digestibility (SID) of protein (CP) and AA of soybean meal (SBM) fed to growing pigs. A corn starch–based diet was formulated with SBM as the sole source of AA and containing titanium as an indigestible marker. Protease was supplemented at 0, 15,000; 30,000 and 45,000 NFP/kg of feed (ProAct 360). An N-free diet was used to estimate basal ileal endogenous AA losses. Ten cannulated pigs (body weight = 21 kg ± 2 kg) were assigned to experimental diets in a duplicate 5 × 5 Latin square design. In Phase I (23 to 30 kg-pigs, 90 ± 17 d of age), ileal digesta was collected in 5 periods of 7 d (5 d adaptation and 2 d ileal digesta collection). In Phase II (50 to 65 kg-pigs. 140 ± 17 d of age), using the same diets, ileal digesta was collected in 5 more periods of 7 d. Pigs were fed at 4% of body weight (BW) adjusted at the end of each period. Diets and ileal digesta were analyzed for CP, AA, and titanium and SID was calculated. Orthogonal polynomial contrasts were used to determine the linear and quadratic effects of protease supplementation. The combined data were analyzed as 4 x 2 factorial, including the fixed effects of protease inclusion (excluding N-free diet), age, and their interactions. In phase I, increasing levels of protease resulted in linear improved (P &amp;lt; 0.1) of SID for the majority of indispensable AA (Except Arg, His, Met + Cys, and Trp) and the average of dispensable AA. In phase II, the SID of Ile, Leu, Met, Met + Cys, Val, the average of indispensable AA, and the majority of dispensable AA was quadratically improved. Overall (Phase I and II), the SID of Ile, Leu, Met + Cys, Val, Cys, Glu, Tyr, and the average of dispensable AA was quadratically improved (P &amp;lt; 0.1). In most cases, the supplementation of 30,000 NFP/kg of feed resulted in the greatest AA digestibility improvements. However, the linear response in the first phase for some AA suggests that diets for younger pigs could be supplemented with a greater level (45,000 NFP/kg of feed). There were no interactions between protease levels and age. Younger pigs had improved (P &amp;lt; 0.1) SID of CP and most AA (Except Cys, Gly, and Ser). In conclusion, dietary protease supplementation can improve SID of AA in soybean mean independent of pig age. Pigs age can influence AA digestibility where younger pigs have greater AA digestibility.

154 Reduction of particle size of field peas increases net energy and digestibility of starch when fed to growing pigs

Abstract Two experiments were conducted to test the hypothesis that particle size of field peas and location of production may affect the apparent ileal digestibility (AID) of starch, the standardized ileal digestibility (SID) of amino acids (AA), and net energy (NE). One source of peas from the U.S., and two sources from Canada were procured. The U.S. peas were ground to 265, 457, or 678 µm, whereas the two Canadian peas were ground to 411 and 415 µm, respectively. A basal diet containing corn and soybean meal as the sources of energy, starch, and AA, and five diets containing corn and soybean meal and 50% of each source of peas were formulated. Pigs were fed the same diets in Exp. 1 and 2, but an N-free diet was also used in Exp. 1. In Exp. 1, barrows [n = 7; initial body weight (BW) = 60.6 kg; SD = 2.1] that had a T-cannula installed in the distal ileum were allotted to a 7 × 7 Latin square design with seven diets and seven periods. Ileal digesta were collected and analyzed for Cr and AA. In Exp. 2, pigs (n = 24; initial BW = 30.8 kg; SD = 1.0) were used in a 6 × 6 Latin square design with six calorimetry chambers and six periods. To determine NE, feces and urine were quantitatively collected and O2 consumption and CO2 and CH4 productions were measured. In both Exp. 1 and 2, the statistical model included diet as the main effect and pairwise comparisons were used to separate the means. Contrast coefficients were also used to determine linear effects of particle size within the U.S. peas. Results from Exp. 1 indicated that the SID of AA was not influenced by the origin of the peas or by particle size, except that the SID of Arg was linearly (P = 0.042) increased (Table 1) as particle size of U.S. field peas was reduced. The AID of starch in the U.S. peas ground to 265 µm was greater (P &amp;lt; 0.05) than in the two Canadian sources, and the AID of starch and NE in diets were linearly (P &amp;lt; 0.001) increased as particle size was reduced. The NE in U.S. peas ground to 678 µm was less (P &amp;lt; 0.05) than in all other pea samples. In conclusion, AID of starch, SID of AA, and NE did not differ between field peas grown in Canada and peas grown in the U.S., but reducing the particle size of field peas resulted in improved digestibility of starch and energy by pigs.

153 Standardized ileal digestibility of amino acids and concentration of metabolizable energy in three sources of corn protein fed to weanling pigs

Abstract Two experiments were conducted to test the hypothesis that the standardized ileal digestibility (SID) of amino acids (AA), apparent total tract digestibility (ATTD) of gross energy (GE), and concentrations of digestible energy (DE) and metabolizable energy (ME) are not different among three sources of corn protein (i.e., new corn protein, ANDVantage 50Y, ANDVantage 40Y) when fed to weanling pigs. In Exp. 1, ileal-cannulated barrows [n = 8; initial body weight (BW) = 11.09 kg; SD = 0.46] were fed an N-free diet or three diets containing each corn protein as the sole source of AA. Pigs were allotted to a replicated 4 × 4 Latin square design with 4 diets and 4 periods of 7 d in each square. Ileal digesta were collected for 2 d and the SID of AA was calculated. In Exp. 2, weanling pigs (n = 32; initial BW = 18.0 kg; SD = 1.21) were fed a corn-based basal diet or three diets containing corn and each source of corn protein. Pigs were housed individually in metabolism crates and feces and urine were quantitatively collected for 5 d after 7 d of adaptation. Concentrations of DE and ME in all diets were calculated and DE and ME in the three sources of corn protein were calculated by difference. Data from both experiments were analyzed using the MIXED procedure of SAS with pig as the experimental unit. In Exp. 1, the statistical model included diet as the fixed effect and square, pig, and period as random effects. In Exp. 2, the model included ingredient as the fixed effect. Results from Exp. 1 demonstrated that the SID of all indispensable AA except Arg and His in ANDVantage 40Y and ANDVantage 50Y were greater (P &amp;lt; 0.05) compared with the new corn protein, but no differences were observed between ANDVantage 50Y and ANDVantage 40Y (Table 1). Results from Exp. 2 indicated that on a dry matter basis, concentration of DE in ANDVantage 50Y was greater (P &amp;lt; 0.05) than in ANDVantage 40Y, the new corn protein, and corn, but ME in ANDVantage 50Y was not different from the ME in the new corn protein (Table 2). Concentration of ME in the new corn protein was not different from ME in corn, ANDVantage 40Y, or ANDVantage 50Y. In conclusion, the new source of corn protein had concentrations of AA that were not different from ANDVantage 50 Y, but this new corn protein had decreased digestibility of AA compared with other corn proteins. The new corn protein also had less DE compared with ANDVantage 50Y, but ME in the new corn protein was not different from corn, ANDVantage 40Y, or ANDVantage 50Y.

Determination and prediction of amino acid digestibility in brown rice for growing-finishing pigs.

The experiment aimed to determine the standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) in 10 brown rice samples fed to pigs, and to construct predictive models for SID of CP and AA based on the physical characteristics and chemical composition of brown rice. Twenty-two cannulated pigs (initial body weight: 42.0±1.2 kg) were assigned to a replicated 11×3 incomplete Latin square design, including an N-free diet and 10 brown rice diets. Each period included 5 d adaptation and 2 d ileal digesta collection. Chromic oxide was added at 0.3% to all the diets as an indigestible marker for calculating the ileal CP and AA digestibility. The coefficients of variation of all detected indices for physical characteristics and chemical composition, except for bulk weight, dry matter (DM) and gross energy, in 10 brown rice samples were greater than 10%. The SID of CP, lysine (Lys), methionine, threonine (Thr), and tryptophan (Trp) in brown rice was 77.2% (62.6% to 85.5%), 87.5% (80.3% to 94.3%), 89.2% (78.9% to 98.9%), 55.4% (46.1% to 67.6%) and 92.5% (86.3% to 96.3%), respectively. The best prediction equations for the SID of CP, Lys, Thr, and Trp were as following, SIDCP = -664.181+8.484×DM (R2 = 0.40), SIDLys = 53.126+6.031×ether extract (EE)+0.893×thousand-kernel volume (R2 = 0.66), SIDThr = 39.916+7.843×EE (R2 = 0.41), and SIDTrp = -361.588+4.891×DM+0.387×total starch (R2 = 0.85). Overall, a great variation exists among 10 sources of brown rice, and the thousand-grain volume, DM, EE, and total starch can be used as the key predictors for SID of CP and AA.

Apparent metabolizable energy and ileal amino acid digestibility of commercial soybean meals of different origins in broilers

We studied the chemical composition and the in vivo AMEn content and apparent (AID) and standardized (SID) ileal digestibility of CP and amino acids (AA) of 27 samples of soybean meals (SBM) from Argentina (ARG), Brazil (BRA), and USA, collected in Spain. On 88% DM basis, the BRA meals had more CP (46.9 vs. 46.0 and 45.9%; P < 0.05) and less sucrose (5.21 vs. 6.28 and 6.47%; P < 0.001) and stachyose (4.20 vs. 4.66 and 4.78%; P < 0.05) than the USA and ARG meals. Urease activity, protein dispersibility index, KOH protein solubility, and trypsin inhibitor activity values, were higher for the USA meals than for the South American meals (P < 0.05). In the in vivo trial, broilers received a common crumble diet from 0 to 16 d of age and then, their respective experimental diets (53% of a N-free diet and 47% of each of the 27 SBM tested) in mash form, for 5 d. The AMEn (2,334 vs. 2,282 and 2,277 kcal/kg; P = 0.062) and the AID (87.3 vs. 86.7 and 86.4%; P = 0.054) and SID (91.9 vs. 91.2 and 90.8%; P < 0.05) of the protein, were greater for the USA meals than for the ARG and BRA meals. In fact, the SID of Lys (93.5 vs. 93.0 and 92.1%; P < 0.001) and of the sum of Lys, Met, Thr, Trp, and Cys (91.4 vs. 91.0 and 90.2%; P < 0.05) were greater for the USA meals than for the ARG and BRA meals. In summary, the chemical composition, protein quality indicators, AMEn content, and ileal digestibility of the CP and the AA of the SBM, varied with the country of origin of the soybeans. In order to increase the accuracy of the feed formulation process, the composition and nutrient content of commercial batches of SBM, by country of origin should be controlled and periodically updated.

Evaluation of exogenous phytase in high-phytate diets for broiler chickens and pigs

There is a gap in the understanding of the relationship between dietary phytate levels and the relative efficacy of phytase to improve amino acid (AA) digestibility in pigs and chickens. Two experiments were conducted to investigate the effect of exogenous phytase on standardized ileal digestibility (SID) of AA and the apparent ileal digestibility (AID) of P in both standard- (SP) and high-phytate (HP) diets for broilers and swine. There were either 40 cages of Cobb 500 male broilers or 10 crossbred barrows (35 kg) fitted with ileal T-cannulas. Both studies were allotted to five dietary treatments (8 replicates). Treatments consisted of four corn-soybean meal-based diets arranged in a 2 × 2 factorial of standard or high phytate and exogenous phytase at 0 or 1 000 phytase units (FYT)/kg; and one N-free diet. Birds were fed a common starter diet from d 0 to 20 and fed experimental diets from d 20 to 25. Birds were euthanized on d 25 via CO2 asphyxiation, and digesta were collected from the terminal ileum. Pigs were fed for a total of four 7-d periods, where digesta were collected on d 6 and 7 of each period. Diet and digesta samples were analyzed for DM, N, Ti, AA, and P to determine AA and P digestibility. The SID of AA was determined by correcting the AID of AA for the basal endogenous losses estimated using the N-free diet. Main effects of the diet type (standard or HP) and phytase (0 or 1 000 FYT/kg), and the interaction of diet type and phytase were evaluated. For both experiments, the HP diets produced lower SID of AA compared to the SP (P < 0.001). For broilers, there was a phytase effect (P < 0.001) for the SID of all AAs evaluated regardless of the diet type. For pigs, phytase improved (P < 0.05) the SID of Met, Lys, Cys, Glu and Ser and tended to improve (P < 0.10) Arg, Leu, Thr, and Tyr. There were no significant interactions for either experiment. For both experiments, AID of P was lower for the HP diets (P < 0.01), and phytase produced greater AID of P for both diet types (P < 0.01). These data indicate that phytase greatly improves the digestibility of P for broilers and pigs and has the ability to significantly increase the digestibility of amino acids for these animals, regardless of the dietary phytate P.

Reduction of particle size of field peas (Pisum sativum L.) increases net energy and digestibility of starch when fed to growing pigs, but there is no difference in nutritional value between peas from the United States and peas from Canada.

Two experiments were conducted to test the hypotheses that particle size of field peas and location where peas are grown do not affect apparent total tract digestibility of nutrients and gross energy, digestible energy (DE), metabolizable energy (ME), and net energy (NE), apparent ileal digestibility (AID) of starch, or standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA). In both experiments, 3 sources of field peas were used. One source was obtained from the United States and 2 sources were obtained from Canada (i.e., Canada 1 and Canada 2). The U.S. field peas were ground to 678, 457, or 265 µm, whereas the 2 sources of Canadian peas were ground to 411 and 415 µm, respectively. Therefore, 5 batches of field peas were used in both experiments. A basal diet contained corn and soybean meal as the only source of energy, starch, and AA, and 5 diets containing corn and soybean meal and 50% of each source of field peas were also formulated. The ratio between corn and soybean meal was 1.92:1 in all diets. In experiment 1, an N-free diet was also used to calculate basal endogenous losses of AA and CP, but in experiment 2, no N-free diet was used. In experiment 1, 7 barrows (initial body weight = 60.6 ± 2.1kg) that had a T-cannula installed in the distal ileum were allotted to a 7 × 7 Latin square design with 7 diets and 7 periods. In experiment 2, 24 pigs (initial body weight = 30.8 ± 1.0kg) were housed in 6 calorimeter chambers with 4 pigs per chamber. The 6 chambers were allotted to one of the 6 diets using a 6 × 6 Latin square design with 6 consecutive periods of 15 d. Results of experiment 1 demonstrated that the SID of CP and AA was not influenced by the origin of the peas or by the particle size, but the AID of starch increased (linear, P < 0.001) as particle size was reduced from 678 to 457 or 265 µm. Results of experiment 2 indicated that growing location did not affect concentrations of DE, ME, or NE of field peas, but concentrations of DE, ME, and NE increased (linear, P < 0.05) when particle size was reduced from 678 to 457 or 265 µm. In conclusion, field peas grown in Canada or the United States have the same nutritional value, but starch digestibility and NE increase if the particle size of field peas is reduced.

Influence of particle size and origin of field peas on apparent ileal digestibility of starch and amino acids and standardized ileal digestibility of amino acids when fed to growing pigs.

The objective was to test the hypothesis that particle size and origin of field peas influence the apparent ileal digestibility (AID) of starch, crude protein (CP), and amino acids (AA) and the standardized ileal digestibility (SID) of AA. Three sources of field peas were procured. One source was from the United States and two sources were from Canada. The U.S. source and one of the sources from Canada (i.e., Canada 1) were each divided into two batches and ground to achieve a target particle size of 250 or 450µm, whereas the other source from Canada (i.e., Canada 2) was only ground to a target particle size of 250µm. Each batch of field peas was included in one diet as the only source of AA. An N-free diet was used to determine the basal endogenous losses of CP and AA. Six barrows (initial weight: 50.5kg; SD = 3.7) that had a T-cannula installed in the distal ileum were randomly allotted to a 6 × 6 Latin square design with six diets and six 7-d periods. Ileal digesta from pigs were collected for 2d after 5d of adaptation. Data were analyzed using a statistical model that included batch of field peas as the fixed effect and animal and period as the random effects. Contrast statements were used to analyze the effects of particle size, origin, and the interaction between particle size and origin. Results indicated that the AID of starch was increased by reducing the particle size in the U.S. source of field peas, but that was not the case for the Canada 1 source (interaction; P < 0.001). Particle size did not influence the AID of CP or AA, but the Canada 2 source of field peas had greater (P < 0.05) AID of Trp, Ala, Cys, Gly, and Tyr than the field peas from the United States. The SID of CP and AA was also not affected by the particle size of field peas. The SID of CP and Trp was greater (P < 0.05), and the SID of His, Ile, and Thr tended (P < 0.10) to be greater in the Canada 2 source compared with the U.S. source, but no differences between the two Canada sources were observed. In conclusion, a few differences in SID of AA between field peas produced in the United States and peas produced in Canada were observed, but there was no effect on SID of AA of reducing the particle size of field peas from 450 to 250µm, whereas the AID of starch increased by reducing the particle size only in the field peas from the United States.

Amino acid supplementation during the adaptation period did not affect the standardized ileal digestibility of amino acids in corn and soybean meal fed to pigs.

The objective was to determine the influence of amino acid (AA) supplementation during the adaptation period on the ileal digestibility of crude protein and AA in corn and soybean meal (SBM) fed to pigs. Six barrows with an initial body weight of 30.9±2.6 kg fitted with a T-cannula at the distal ileum were assigned to a 6×6 Latin square design with 6 dietary treatments and 6 periods. Two experimental diets contained corn or SBM as the sole AA source and an N-free diet was additionally prepared. For AA supplementation groups, an AA mixture consisted of Gly, Lys, Met, Thr, Trp, Ile, Val, His, and Phe was added to the corn diet and the N-free diet at the expense of cornstarch, and an AA mixture of Lys, Met, and Thr was added to the SBM diet. All diets contained 0.5% of chromic oxide. The 6 experimental diets were fed to the pigs for four and half days, and the 3 diets containing an AA mixture were switched to the respective diets without AA mixture during the following two and half days. Ileal digesta were collected on days 6 and 7. The addition of an AA mixture during the adaptation period increased apparent ileal digestibility of Arg and Trp in corn (p<0.05) but did not affect that in SBM. The addition of an AA mixture during the adaptation period increased apparent ileal digestibility of Pro and Gly regardless of feed ingredient (p<0.05) but did not affect that of other AA. All AA except Pro in corn and SBM were unaffected by the addition of the AA mixture during the adaptation period. The addition of amino acids to a low-protein diet during the adaptation period does not affect the standardized ileal digestibility of indispensable amino acids in pigs.

153 Effect of Exogenous Phytase on the Digestibility of Amino Acids and Phosphorus in Standard and High Phytin Swine Diets

Abstract The objective of the following study was to investigate the effect of exogenous phytase (Hiphorius 40, DSM Nutritional Products) on the standardized ileal digestibility (SID) of amino acids (AA) and the apparent ileal digestibility (AID) of P in both standard and high phytin (HP) swine diets. The study consisted of 4 diets arranged in a 2 x 2 factorial of standard or high phytin and exogenous phytase at 0 or 1,000 FYT/kg; and one N-free diet. Ten crossbred male pigs fitted with ileal T-cannulas were allotted to the 5 dietary treatments in duplicate 5 x 4 incomplete Latin-square design. Pigs were fed for a total of four 7-d periods, where digesta was collected on d 6 and 7 of each period. Diet and digesta samples were analyzed for dry matter, N, Ti, AA, and P to determine AA and P digestibility. The SID of AA was determined by correcting the AID of AA for the basal endogenous losses estimated using the N-free diet. Data were subjected to an ANOVA where main effects of the diet type (standard vs. HP) and phytase were evaluated as well as the interaction of diet type and phytase. If the ANOVA was significant the means were separated by Tukey’s method. The basal endogenous AA losses of pigs in this study ranged from 0.115 (Met) to 0.921 (Thr) g/kg DM and 0.308 (Cys) to 9.455 (Pro) g/kg DM for indispensable and dispensable AA, respectively. The HP diets produced less SID of all AA compared with the standard diets (P &amp;lt; 0.001) with an average SID reduction of 6.5% for indispensable AA. Phytase improved (P &amp;lt; 0.05) the SID of Met, Lys, Arg, Cys, Glu and Ser and tended to improve (P &amp;lt; 0.10) Leu, Thr, and Tyr. There were no significant diet type*phytase interactions. The AID of P was less (P &amp;lt; 0.01) for the HP diets relative to the standard (39.12% vs. 45.84%), and phytase produced greater (P &amp;lt; 0.01) AID of P for both diet types (25.62% vs. 59.34%). These data indicate that phytase can improve the digestibility of many AA and P in both standard and HP diets for growing pigs.

303 Interactive Effects of Pelleting and Particle Size Reduction of Corn on Ileal Digestibility of Starch and Amino Acids in Corn-Soybean Meal Diets Fed to Pigs

Abstract The objective was to determine the interactive effects of particle size reduction and pelleting on the apparent ileal digestibility (AID) of starch and the standardized ileal digestibility (SID) of amino acids (AA) in corn-soybean meal diets fed to pigs. Six corn-soybean meal based diets were arranged in a 3 × 2 factorial with 3 particle sizes of corn (i.e., 700, 500, or 300 μm) and 2 diet forms (i.e., meal or pelleted). An N-free diet was also used and there were, therefore, a total of 7 diets. Pigs were allowed ad libitum access to feed and water. Pigs (n = 7; initial body weight = 59.30 kg; SD = 2.77) that were equipped with a T-cannula in the distal ileum were allotted to the 7 diets using a 7 × 7 Latin square design with 7 periods. Ileal digesta were collected for 2 days after 5 days of adaptation. The statistical model included diet as fixed effect and pig and period as random effects. Contrast coefficients were used to determine effects of diet form, linear effects of particle size, and the interaction. Results indicated that the AID of starch was linearly increased (P = 0.001) with reduced particle size of corn and pelleted diets had greater (P = 0.029) AID of starch than meal diets (Table 1). The SID of Leu, Lys, Met, Phe, Thr, and Val linearly increased with reducing particle size, but the increase was greater in pelleted diets than in meal diets (interaction, P &amp;lt; 0.05). The SID of Arg, His, Ile, and Val also linearly increased (P &amp;lt; 0.05) as the particle size of corn was reduced, and the SID of all indispensable AA except Trp was greater (P &amp;lt; 0.05) in pelleted diets than in meal diets. In conclusion, reducing the particle size of corn from 700 to 300 μm increased the AID of starch and the SID of AA, but the AID of starch and the SID of most indispensable AA was greater in pelleted diets than in meal diets. If there were interactions, the effects of reducing particle size were greater when corn particle size was reduced from 500 to 300 μm in meal diets and from 700 to 500 μm in pelleted diets.