Amino Acids In Corn Research Articles

PSX-1 Data Analytics of a Global Nirs Database of Corn Nutrient Content

Abstract Corn is the primary energy source for livestock and poultry. Corn nutrient composition and energy value vary due to genetics, country of origin, agronomic, harvest, and storage conditions. Analytical variability among and within-labs makes it more difficult to detect differences among sources and establish nutrient interrelationships to estimate amino acid (AA) content based on crude protein (CP), which is less variable. Near-infrared reflectance spectroscopy (NIRS) can standardize feedstuff evaluation and increase the sample size. The PNE system (Adisseo) has distinctive NIRS curves created using direct calibrations with in vivo data of standard chicken metabolizable energy (AME and AMEn) and AA digestibility studies. This study assessed the link between AA concentrations and CP and among proximate parameters (CP, crude fiber, ether extract, nitrogen-free extract, and ash), starch, AA concentrations and digestibilities with AME and AMEn. The PNE database used includes 84,331samples of maize scanned in diverse countries between 2018 and 2021 that came from Argentina (7,654), Brazil (49,672), Indonesia (18,072), Philippines (4,747), and the United States (4,186). Correlation and regression analyses between AA and CP were performed. The pairwise correlations (P < 0.001) observed between AA and CP ranged between 0.52 and 0.90. The positive linear associations with CP content can be used to predict the concentrations of all AAs in corn (P < 0.001). However, coefficients of determination (R2) ranged from 0.27 (Trp) to 0.80 (Val) or 0.81 (Phe). Prediction equations for Lys, sulfur AAs had lower R2 values (0.37 to 0.47). Although the country of origin and CP interacted (P < 0.001), R2 modestly increased when added to these models. The estimation of AME and AMEn based on proximate values, starch, amylose, amylose:amylopectin, AA concentrations, AA digestibility, and country of origin was done using multiple linear regression (MLR) and neural networks (NN) analysis. All factors were significant (P < 0.001), and MLR models including starch and amylopectin, had the best fit for AME (R2 = 0.87, AICc = 149,635) and AMEn (R2 = 0.87, AICc = 149,543). The NN models had a better fit for training and validation datasets for AME (R2 = 0.95, RASE = 15.18) and AMEn (R2 = 0.95, RASE = 15.23). The NN models helped to visualize the greater importance of starch, AA concentration (Trp, Ile, Thr), and Leu digestibility. In summary, some corn AA concentrations (Val, Phe, Ile) may be predicted from their CP content; other AA concentrations may be more difficult to predict. Corn AA content varies by country of origin and independent of CP content. Starch content, AA concentration, and AA digestibility are essential factors in determining energy value of corn. Relevant nutritional aspects were elucidated by data analytics of a NIRS database with direct calibration of in vivo parameters of energy utilization and AA digestibility.

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.

Comparison of methods for estimating basal endogenous losses of amino acids and additivity of digestibility of amino acids in corn and soybean meal for broilers

This study was to compare the estimates of basal endogenous losses (BEL) of amino acids (AA) determined by 3 methods including feeding a nitrogen-free diet (NFD) or a low-casein diet (LCD, containing casein at 30 g/kg diet) or using the regression method. Another objective was to investigate whether the ileal AA digestibility of corn calculated from a casein-supplemented corn diet is additive for a corn-soybean meal (SBM) mixed diet in broilers. On d 31 of age, 168 Ross 308 male broilers were assigned to 8 dietary treatments with 6 replicates in a randomized complete block design. An NFD and 3 diets containing 30, 60, or 90 g/kg of casein were formulated to determine the BEL of AA and ileal AA digestibility of casein. The other 4 diets consisted of a corn diet, SBM diet, casein-supplemented corn diet, and corn-SBM mixed diet. On d 35 of age, digesta from the distal section of the ileum were collected. The BEL of AA in birds fed the LCD were greater (P < 0.05) than those of the NFD and the regression method. There were no differences in the BEL of AA determined between the NFD and the regression method. Apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of AA for corn calculated from the casein-supplemented corn diet were greater (P < 0.05) than those of the corn diet. The predicted AID of Thr in the corn-SBM mixed diet based on the AID of AA for corn in the corn diet was lower (P < 0.05) than the measured AID. However, the predicted AID of AA in the mixed diet based on the AID of AA for corn in the casein-supplemented corn diet did not differ from the measured AID. The predicted SID of AA in the mixed diet did not differ from the measured SID irrespective of casein supplementation. In conclusion, feeding an NFD or using the regression method yields similar BEL of AA, but not feeding an LCD. Casein supplementation in the corn diet increases the ileal AA digestibility for corn, which is additive for the corn-SBM mixed diet.

Influence of age and type of feed ingredients on apparent and standardized ileal amino acid digestibility in broiler chickens.

Two experiments were conducted to determine the effects of bird age on apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of amino acids (AA) for 10-d-old Experiment (Exp. 1) and 22-d-old (Exp. 2) male broilers. This study investigated the effects of different broiler ages and feed ingredients on AID and SID of AA in corn and soybean meal (SBM). Four hundred and eighty (age = 7 d; initial body weight [BW] = 173.4 ± 12.65 g) and 192 (age = 18 d; initial BW = 772.2 ± 62.13 g) birds were allocated to three dietary treatments in a randomized complete block design with eight replicate cages per treatment. Two diets were formulated based on corn or SBM as the sole source of AA in the diet. A nitrogen-free diet was also formulated to measure basal endogenous losses of AA. Experimental diets were given for 3 and 4 days in Exps. 1 and 2, respectively. An interaction was observed (p < 0.05) between the age of birds and the type of ingredient for the AID of most AA, except for methionine, valine, cysteine (Cys), and tyrosine; however, the effects of age and type of ingredients were diminished in the SID of AA, except for histidine, isoleucine, leucine (Leu), phenylalanine, alanine (Ala), and glutamic acid (Glu). The AID of AA, except for Leu and Cys and the SID of AA, except for Leu, Ala, Glu, and Pro in SBM were greater (p < 0.05) than in corn. As the age of birds increased from 10 to 22 d, digestibility of all AA increased (p < 0.05), regardless of the expression of AA digestibility (i.e., AID and SID). In conclusion, the AID and SID of AA in both corn and SBM increased with increasing age, and the AID and SID of AA in SBM were greater than in corn.

Evaluating growth response of broiler chickens fed diets supplemented with synthetic DL-methionine or DL-hydroxy methionine: a meta-analysis

Methionine (Met) is the first limiting amino acid in corn and soybean meal-based diets (containing L-Met) in broiler chickens, which are often supplemented with synthetic DL-Met or DL-Hydroxy Met (OH-Met). Our objective was to quantitatively assess the efficacy of synthetic Met sources and determine differences in growth rate of broilers fed at or below requirements in response to Met intake. A systematic literature search resulted in building a database containing 480 treatment means from 39 articles published between 1985 and 2019 globally. The database was divided into starter, grower, and finisher subsets based on the age of the broilers. For each subset, linear-plateau and quadratic-plateau models were fitted to determine Met or sulfur amino acid (SAA; Met + Cysteine) requirements using average daily gain as a response variable. For each phase, 4 new subsets were obtained by only retaining records with digestible Met or SAA intake at or below requirement by linear-plateau or quadratic-plateau models. Then, a linear model (without plateau) was fitted for all new subsets for each rearing phase using supplemental digestible synthetic Met or SAA intake (basal Met intake was subtracted from total Met intake) as independent variables. The basal diet was made of only raw materials without supplementation of any synthetic Met source. Finally, the models were extended to evaluate source of synthetic Met effects on the slope parameter. At all stages of model fitting, the inclusion of a random study effect was evaluated for each parameter. All models were fitted within a Bayesian framework, for which minimally informative priors were used. The best models, that is, the most accurate inclusion of random effects, were selected based on at least 10-point difference in leave-one-out cross-validation information criterion. Model selection criteria did not consistently favor either of the linear- and quadratic-plateau models to determine Met or SAA requirements across broiler growth phases. Extending models with covariates (e.g., dietary energy and amino acids) did not improve any model fit. Body weight gain response of broiler chickens to the 2 sources was not different when fed at or below Met requirements for any of the growth phases.

Influence of Age on the Standardized Ileal Amino Acid Digestibility of Corn and Barley in Broilers.

Simple SummaryEfficient amino acid (AA) utilization in broilers is crucial concerning the accuracy of feed formulation, economy of diet and minimizing nitrogenous pollution in the environment. A range of factors (ingredient type, age, sex, feed form and bird type) can affect the AA digestion in poultry. The first week of broiler life is considered the most critical period while chicks source nutrition from residual yolk. Dynamic changes are noted in the digestive tract development, secretion and activity of protein digestive enzymes during the first few weeks in broiler. Limited data exist on the age effect on AA digestibility in broilers, and the results are paradoxical. The aim of the present study was to investigate the influence of age on the standardized ileal digestibility coefficients (SIDCs) of AAs in corn and barley from hatching to the end of the broiler growth cycle (day 42). Based on the results, the age influence on AA digestibility is grain- and AA-dependent. The pattern of the age effect on the SIDC AA in corn was not consistent. In the case of barley, the SIDC AA increased with advancing age.The aim of this study was to determine the standardized ileal digestibility coefficients (SIDCs) of nitrogen (N) and amino acids (AAs) in corn and barley at six different ages (days 7, 14, 21, 28, 35 and 42) of broilers using the direct method. The apparent AA digestibility coefficients were corrected using age-appropriate basal endogenous AA losses. No age effect (p > 0.05) was noted for the SIDC of N in corn. The average SIDC of indispensable AAs (IAAs) and total AAs (TAAs) was influenced in a quadratic manner (p < 0.05) with the values being higher at day 7 that decreased at day 14, increased and plateaued between days 21 and 35 and dropped again at day 42. The average SIDC of dispensable AAs (DAAs) was influenced linearly (p < 0.05). In barley, the SIDC of N and average IAAs, DAAs and TAAs was affected (quadratic; p < 0.001) by age. The digestibility increased from day 7 to 21 and then plateaued up to day 42. The present findings confirm that the SIDC of AA in corn and barley are influenced by broiler age and that the age effect on AA digestibility may need to be considered for precise feed formulation.

The effect of natural feed additive on productive performance of broiler chickens

The effect of natural feed additive on productive performance of broiler chickens

Canonical interrelationships in morphological characters, yield and nutritional components of corn

The increase in the world population, the need to increase food production, both in quantity and quality, becomes increasingly prominent. The objective of this work was to identify the canonical correlations between yield components, morphological characters, micronutrients, bioactive compounds and amino acids in corn. The experimental design used was a randomized block containing 11 treatments arranged in three replications. The treatments consisted of 11 Top Crosses hybrid genotypes, these being made through crosses directed between a narrow genetic base tester hybrid for specific combining ability with 11 S5 inbred lines. It is inferred that groups considered yield components, secondary traits, bioactive compounds, micronutrients and amino acids are dependent. Promising characters are identified for the corn breeding for high yields, nutritional and energetic quality of corn grains. The indirect selection of grains with additions in essential amino acids can be directed to plants with superiority in height, mass and width of grains, phenols, flavonoids, soluble solids and zinc content.

Effect of the extrusion process on the amino acid components profile of the broilers diet

The paper presents the studies results of the extrusion process effect on changes in the amino acid profile of the diet components for broilers. The amino acid composition of wheat bran was higher in all indicators relative to corn, so there was a predominance in the content of arginine by 77.5 %, lysine-62 %, valine-61.8 %, threonine-53.6 %, glycine-68.5 %, phenylalanine -52.9 %, threonine-53.6 % (p≤0.001), histidine – 60.5 % (p≤0.01). The extrusion of wheat bran led to a quantitative decrease in amino acids, there was a decrease in histidine by-28.95 %, valine-20 %, serine – 17.81 %, lysine-16 %, proline-14.9 %, threonine-10.72 %. At the same time, there was an increase in the concentration of amino acids in corn after extrusion relative to the native form, which was for arginine -80%, histidine -33%, proline–13%, alanine–11%. The concentration of tyrosine, on the contrary, decreased by 20%. At the same time, the extrusion process retained the predominance of the amino acid composition of wheat bran over corn for all the amino acids considered, except methionine.

138 Effects of Increasing Soybean Meal in Corn-based Diets on Growth Performance of Late-finishing Pigs

Abstract Two experiments were conducted to determine the effects of increasing levels of soybean meal (SBM) replacing feed grade amino acids in corn or corn-dried distillers grains with solubles (DDGS)-based diets on growth performance of late finishing pigs. In both experiments, there were 22 to 27 pigs per pen and 14 pens per treatment. Average length of the experiments was 35 (Exp. 1) and 29 days (Exp. 2). Diets were balanced to contain 0.70% SID Lys and 2,667 or 2,610 kcal NE/kg for Exp. 1 and 2, respectively. Minimum amino acid ratios relative to Lys were: Ile, 55; Met&amp;Cys, 60; Thr, 65; Trp, 19.5, and Val, 70. Dietary crude protein ranged from 10.1 to 15.2 for Exp. 1 and 13.6 to 19.4 for Exp. 2. The statistical model considered fixed effects of treatment, linear and quadratic contrasts, and random effect of block. In Exp.1, 1,793 pigs (L337×1050, PIC; initially 104.9 ± 1.4 kg) were fed corn-based diets and pens of pigs were assigned to 1 of 5 dietary treatments with increasing SBM from 5 to 20%. Overall, average daily gain (ADG) and gain-to-feed (G:F) increased (linear; P &amp;lt; 0.05) as SBM increased with the greatest improvement observed as SBM increased from 5 to 8.75%, with little improvement thereafter. In Exp. 2, 1,827 pigs (L337×1050, PIC; initially 97.9 ± 1.1 kg) were used in a similar study as Exp. 1, but all diets contained 25% DDGS and SBM levels increased from 0 to 16%. Overall, G:F and final bodyweight of pigs marginally improved (linear and quadratic, respectively; P &amp;lt; 0.10) as SBM increased, with the greatest performance observed when diets contained 8% SBM. These results suggest that increasing SBM up to 8% at the expense of feed grade amino acids in corn or corn-DDGS-based diets improved ADG or G:F in late-finishing pigs.

PSII-23 Addition of Hydrogen Chloride to Collection Bags or Containers Did Not Change Basal Endogenous Losses or Digestibility of Amino Acid in Corn, Soybean Meal, or Wheat Middlings Fed to Growing Pigs

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

PSVI-13 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

Abstract 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). Six barrows with an initial body weight of 30.9 ± 2.6 kg fitted with a T-cannula in 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 source of AA 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 4 and half days, and the 3 diets containing AA mixture were switched to the respective diets without AA mixture during the following 2 and half days. Ileal digesta were collected during the last 2 days. The addition of AA mixture during the adaptation period caused increased apparent ileal digestibility of Arg and Trp in corn (P &amp;lt; 0.05), but did not affect that in SBM. The addition of AA mixture during the adaptation period caused increased apparent ileal digestibility of Pro and Gly regardless of feed ingredient (P &amp;lt; 0.05), but did not affect that of other AA. All AA except Pro in corn and SBM were unaffected by the addition of AA mixture during the adaptation period. In conclusion, the addition of amino acid during the adaptation period does not affect the standardized ileal digestibility of indispensable amino acids in feed ingredients.

Addition of hydrochloric acid to collection bags or collection containers did not change basal endogenous losses or ileal digestibility of amino acid in corn, soybean meal, or wheat middlings fed to growing pigs.

ObjectiveThe 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.MethodsTwenty-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.ResultsThere 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.ConclusionIt is not necessary to add acid to digesta collection bags or collection containers if ileal digesta are stored at −20°C immediately after collection.

Crystalline amino acids do not influence calculated values for standardized ileal digestibility of amino acids in feed ingredients included in diets for pigs.

An experiment was conducted to test the hypothesis that addition of crystalline amino acids (AA) to diets during the adaptation or collection periods will not influence calculated values for apparent ileal digestibility (AID) or standardized ileal digestibility (SID) of AA in corn and soybean meal (SBM). Seven ileal-cannulated barrows (initial body weight: 77.9 ± 2.6 kg) were allotted to a 7 × 7 Latin Square design with 7 dietary treatments and 7 periods. Dietary treatments included feeding diets based on corn or SBM without or with crystalline AA for the entire 7-d period or with crystalline AA during the adaptation period, but without crystalline AA during the collection period. An N-free diet was also used. Each experimental period consisted of 5 d of adaptation to the diets followed by 2 d of ileal digesta collection, with digesta being collected for 9 hr/d starting after feeding the morning meal. Thus, the entire experiment lasted 49 d. The AID and SID of crude protein (CP) and AA were calculated using values determined in corn or in SBM without or with crystalline AA to determine if crystalline AA influenced calculated values for AID or SID of CP and AA. Results indicated that addition of crystalline AA to diets fed during the entire 7-d period increased (P < 0.05) AID of some AA in corn and SBM. However, no differences in SID of CP and AA were observed between pigs fed the diets without crystalline AA and pigs fed the diets with crystalline AA if dietary crystalline AA were ignored in calculations of SID values. This indicates that crystalline AA were 100% absorbed before the distal ileum and did not affect calculated values for SID of AA if calculations were based only on the AA in corn or SBM. Therefore, it is concluded that crystalline AA may be added to experimental diets in digestibility experiments before and during collection periods without affecting results, if crystalline AA are disregarded in the calculation of AID or SID of AA in ingredients.

The direct and difference procedures result in similar estimates for amino acid digestibility in feed ingredients fed to growing pigs.

An experiment was conducted to test the hypothesis that values for standardized ileal digestibility (SID) of amino acids (AA) in corn, wheat, and wheat middlings obtained using the direct procedure are not different from values obtained using the difference procedure. Sixteen ileal-cannulated barrows (initial BW: 69.5 ± 5.0 kg) were allotted to a replicated 8 × 4 Youden Square design with 8 diets and 4 periods. Each period consisted of 5 d of adaptation to the diet and 2 d of collection of ileal digesta. 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, SBM and wheat, or SBM and wheat middlings, and an N-free diet was also used. The apparent ileal digestibility (AID) and the SID of crude protein (CP) and AA for the 4 diets containing SBM, corn, wheat, or wheat middlings as the sole source of AA were calculated using the direct procedure. The AID and SID of CP and AA for the 3 mixed diets containing SBM and corn, wheat, or wheat middlings were also calculated and the contribution of digestible AA from SBM was subtracted from the AID or SID values for the diets. The AID or SID of AA in corn, wheat, and wheat middlings were subsequently calculated by difference. Results indicated that the AID values for a few AA were lower (P < 0.05) if the direct procedure was used instead of the difference procedure, regardless of ingredient. The AID of Trp was greater in corn and wheat middlings, and the SID of Trp in corn and wheat middlings tended to be greater, if the direct procedure rather than the difference procedure was used, but that was not the case for wheat (interaction, P < 0.05 and P < 0.10, respectively). However, for all other indispensable AA, and for most of the dispensable AA, the SID of AA in corn, wheat, and wheat middlings was not different between the difference procedure and the direct procedure. Therefore, values for SID of AA in cereal grains and fiber-rich ingredients may be determined using either the direct or the difference procedure.

Digestibility of amino acids, fiber, and energy by growing pigs, and concentrations of digestible and metabolizable energy in yellow dent corn, hard red winter wheat, and sorghum may be influenced by extrusion

Two experiments were conducted to determine effects of extrusion on energy and nutrient digestibility in cereal grains fed to growing pigs. One source of yellow dent corn, one source of hard red winter wheat, and one source of sorghum were ground to approximately 300 microns and each source of grain was divided into 2 batches. One batch of each grain was extruded, whereas the other batch was used without further processing. In Exp. 1, 7 diets were formulated to determine ileal starch and amino acid (AA) digestibility in the grains. Three diets contained the non-extruded grains and 3 diets contained the extruded grains. The last diet was an N-free diet that was used to determine basal endogenous losses of AA from the pigs. Seven growing barrows (initial body weight = 14.2 ± 0.9 kg) had a T-cannula installed in the distal ileum and were allotted to a 7 × 7 Latin square. Each experimental period lasted 7 days with the initial 5 days being the adaptation period and ileal digesta were collected on days 6 and 7. Results indicated that extruded grains had greater (P < 0.001) apparent ileal digestibility (AID) of starch than non-extruded grains. Extrusion also increased standardized ileal digestibility (SID) of crude protein (CP) and all AA except Lys and Pro in corn, but the SID of CP and AA in wheat and sorghum was not affected by extrusion. In Exp. 2, 6 diets were used. Three diets contained the non-extruded corn, wheat, or sorghum, and 3 diets contained the extruded grains. Forty eight growing barrows (initial body weight = 15.1 ± 3.7 kg) were allotted to a randomized complete block design. Pigs were housed individually in metabolism crates and feces and urine were collected separately for 5 days after 5 days of adaptation. The apparent total tract digestibility (ATTD) of gross energy was increased by extrusion of corn or sorghum, but that was not the case for wheat (interaction, P < 0.001). The ATTD of neutral detergent fiber in wheat was reduced by extrusion, but not in corn and sorghum (interaction, P < 0.001). However, extrusion reduced (P < 0.05) the ATTD of acid detergent fiber in all grains. Extrusion increased the digestible energy (DE) and metabolizable energy (ME) in corn and sorghum (DM-basis) compared with non-extruded grains, but there was no increase in DE and ME (DM-basis) if wheat was extruded (interaction, P < 0.001). In conclusion, extrusion increased the AID of starch in all grains and the ATTD of energy and the DE and ME in corn and sorghum. The SID of most AA in corn was also increased by extrusion.

Additivity of Ileal Amino Acid Digestibility in Diets Containing Corn, Soybean Meal, and Corn Distillers Dried Grains with Solubles for Male Broilers.

Simple SummaryThere is limited information on the additivity on ileal digestibility of amino acids (AAs) in poultry diets containing corn distillers dried grains with solubles. The aim of this study was to test additivity of two types of ileal digestibility of AAs in mixed diets containing corn, soybean meal, and corn distillers dried grains with solubles in male Ross 308 broiler chickens. The apparent ileal digestibility of some amino acids in feed ingredients used in the study was not additive in mixed diets, whereas the standardized ileal digestibility of most amino acids was additive. Based on the results, standardized ileal digestibility values are more additive in poultry diets containing various feed ingredients compared with apparent ileal digestibility values.The aim was to test additivity of apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of amino acids (AAs) in mixed diets for Ross 308 broiler chickens. Two hundred and eighty-eight, 20-d-old male broiler chickens were assigned to one of six diets, with six birds per cage using a randomized complete block design. The diets consisted of a nitrogen-free diet, three diets containing corn, soybean meal (SBM), and corn distillers dried grains with solubles (CDDGS) as the sole source of nitrogen, respectively, and two mixed diets containing corn, SBM or CDDGS. Chromic oxide was added to the diets as an indigestible index. On day 24, birds were euthanized for ileal digesta collection. Relative proportion of the basal endogenous loss of AAs to total ileal outflow of AAs in corn was greater (p < 0.05) than that of SBM and CDDGS. For the corn-SBM and corn-SBM-CDDGS mixed diets, the AID of AAs differed (p < 0.05) from the predicted values. No difference was observed between the measured and predicted SID of AA. In conclusion, the SID of AAs is more additive in mixed diets containing corn, SBM, or CDDGS compared to AID values.

Toward standardized amino acid matrices for exogenous phytase and protease in corn–soybean meal–based diets for broilers

A total of 468 male Ross 308 broilers were used in a digestibility study to determine the additivity of apparent or standardized amino acid (AA) digestibility values for corn, soybean meal (SBM), or a mixture of corn and SBM that were supplemented, or not, with either phytase, protease, or a combination of phytase and protease. These treatments generated a total of 12 experimental diets that were arranged in a 3 × 4 design. A nitrogen-free diet was also fed to estimate endogenous AA loss. Apparent and standardized AA digestibility values were assessed on day 28 posthatch. The apparent digestibility of AA in the complete diet was higher (P < 0.05) than expected based on the digestibility of the corn and SBM individually. However, this overestimation was corrected by the adjustment to standardized values. Importantly, addition of protease or the combination of protease and phytase increased (P < 0.05) the digestibility of AA in corn and SBM. Furthermore, these effects were arithmetically coherent with respect to the measured effects of the enzymes in the mixture of corn and SBM, even improving the additivity of AA digestibility values when assessed on an apparent basis. This study demonstrates that the effect of exogenous protease and phytase on AA digestibility in complete diets is predictable based on measurements made in individual ingredients. In addition to improving digestibility values per se, exogenous protease and phytase may enhance precision in least cost formulation systems.

116 Direct vs. difference method to determine amino acid digestibility in ingredients fed to pigs

Abstract 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 &lt; 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.

Ileal digestibility of amino acids in corn condensed distiller’s solubles and whole stillage for pigs

The immense growth in global bioethanol production has greatly increased the supply of by-products such as whole stillage and condensed distiller’s solubles, which could be potentially used for animal feeding. The objective of this experiment was to determine apparent ileal digestibility coefficients (AID) and standardized ileal digestibility coefficients (SID) of crude protein and amino acids in corn condensed distiller’s solubles (CCDS) and corn whole stillage (CWS) when fed to pigs. A total of 18 finishing barrows with an average initial body weight 79.4 ± 4.5 kg and a simple T cannula in the distal ileum were used in this experiment. Two test diets were formulated with CCDS or CWS as the sole source of amino acids, and a nitrogen free diet was used for estimation of basal ileal endogenous losses of crude protein and amino acids. The direct procedure was employed for calculation of AID and SID in the two by-products. Compared with CWS, CCDS had higher SID of crude protein (0.864 vs. 0.796; P = 0.03) and lysine (0.821 vs. 0.743, P = 0.10), but lower SID of methionine (0.730 vs. 0.831, P = 0.009), and similar SID of threonine (0.762 vs. 0.710, P = 0.26), tryptophan (0.862 vs. 0.863, P = 0.98), and cysteine (0.675 vs. 0.686, P = 0.74). The information generated from this experiment can be used for formulation of swine diets containing these two ethanol by-products.