Standardized Ileal Digestibility Coefficients Research Articles

Effect of age on the standardized ileal amino acid digestibility of soybean meal and canola meal in broilers

Standardized ileal digestibility coefficients (SIDC) of nitrogen (N) and amino acids (AA) in two protein sources (soybean meal [SBM] and canola meal [CM]) were investigated at six broiler ages (d 7, 14, 21, 28, 35, and 42). Two assay diets were formulated to contain either SBM (413 g/kg) or CM (553 g/kg) as the sole dietary AA source. Titanium dioxide (5 g/kg) was added as an indigestible marker. A total of 696 male broilers at 1 d old were allotted to 12 replicate cages per age group. Each assay diet was offered to birds for 4 d prior to the ileal digesta collection on d 7 (14 birds/cage), 14 (12 birds/cage), 21 (10 birds/cage), 28 (8 birds/cage), 35 (8 birds/cage) and 42 (6 birds/cage), respectively. The apparent digestibility coefficients were standardized using age-specific basal endogenous AA flows. In the SBM group, though the SIDC of N tended to be influenced (quadratic; P = 0.075) by age, no linear or quadratic response of age effect was observed on the average SIDC of indispensable (IAA) and total AA (TAA). An age effect (quadratic; P < 0.05) was observed on the average SIDC of dispensable AA (DAA) in SBM with the highest value recorded at d 7, followed by a decrease from d 14 to 28, which increased beyond d 35. The SIDC of some individual AA (Arg, Thr, Trp, Cys, Pro) were affected (P < 0.05 or P < 0.001) in a quadratic manner by age. In the CM, the SIDC of N, average SIDC of IAA, DAA and TAA were influenced (quadratic; P < 0.05 or P < 0.001) by age. The SIDC of N and average SIDC of DAA and TAA were higher from d 7 to 14, declined at d 21, and then increased beyond d 28. The average SIDC of IAA was low between d 7 and 28 and increased thereafter. The SIDC of individual AA were affected (linear or quadratic; P < 0.05 or P < 0.001) by different magnitudes by age. The age influence on the SIDC AA was variable, depending on the protein source and AA. The results demonstrate that age-specific SIDC AA data might need consideration in broiler feed formulations.

Total amino acid level affects the results of standardized ileal digestibility assays for feed ingredients for swine.

It has been demonstrated that the fiber content of oilseed meals and total amino acids (AA) in distillers' grains products affects standardized ileal digestibility (SID) values from swine assays and that total protein concentration affects the AA digestibility in assays using chickens. This analysis was conducted to test the hypothesis that the total AA content of test samples affects the SID assay results. Databases containing total AA profiles and SID values of 20 feedstuffs commonly fed to pigs from 2 sources, AMINODat 5.0 (Evonik Industries, 2015) and the Nutrient Requirements of Swine, 12th edition (NRC, 2012) were used to compare AA concentration effects on standardized ileal digestibility coefficients. Databases were compared with AA and SID available in both data sets. The total AA values were similar for the 2 databases with an R 2 of 0.979 (P<0.001). The linear relationship between digestibility coefficients from the 2 databases was highly significant, an R 2 of 0.810 (P<0.001). Both databases had increased SID values with increasing AA contents within and across feed ingredients. The SID=f(AA concentration) relationship was confirmed with an individual paper. Since SID, as typically measured, is a function of both digestion and absorption, both processes following Michaelis-Menten kinetics, SID=f(AA concentration) may simply be a natural phenomenon. Other reasons for the relationship were explored. Methods of estimating endogenous AA losses and misapplication statistical procedures may contribute to variation in results and at least partially explain why SID=f(AA concentration).

Determination and prediction of digestible energy, metabolizable energy, and standardized ileal digestibility of amino acids in barley for growing pig

Two experiments were performed to determine the digestible energy (DE), metabolizable energy (ME) and standardized ileal digestibility coefficients (SIDC) of amino acids (AA) in barley for pigs, and to develop prediction equations for the DE, ME and SIDC of AA based on its chemical composition. In Exp. 1, twenty-two castrated male pigs (29.5 ± 1.3 kg) were allotted to a replicated 11 × 3 incomplete Latin square design, including 11 diets and 3 consecutive periods. A corn-soybean meal basal diet and 10 test diets containing 400 g/kg of each barley at the expense of corn and soybean meal were prepared, and all diets had a constant ratio of corn to soybean meal. Each period includes 7 d of adaption and 5 d of total feces and urine collection. The DE and ME contents were measured by the total collection method. In Exp. 2, twenty-two ileal-cannulated pigs (30.5 ± 2.1 kg) were used in a duplicated 11 × 3 incomplete Latin square design with 11 diets and three 7-day periods. Titanium dioxide (3 g/kg) was added to all diets as indicator and ieal digesta were collected on d 6 and 7 of each period. Barley was the sole nitrogen source in 10 barley diets and a nitrogen-free diet was used for the endogenous nitrogen losses. The results showed great variations in ether extract (EE), calcium (Ca), ash, acid detergent fiber (ADF) and crude fiber (CF) among samples of barley. On an air-dry basis, the DE and ME in barley for pigs were 12.26 (11.29–13.58) MJ/kg and 11.87 (10.95–13.15) MJ/kg, respectively. The optimal prediction equations for DE and ME were: DE (MJ/kg) = −23.594 + 0.358 crude protein (CP) + 0.043 EE (R2 =0.95) and ME (MJ/kg) = 0.338 + DE - 0.014 ADF (R2 =0.99), respectively. The SIDC of lysine (Lys), methionine (Met), threonine (Thr), and tryptophan (Trp) in barley were 0.767 (0.731–0.809) g/kg, 0.825 (0.803–0.872) g/kg, 0.809 (0.793–0.822) g/kg, and 0.794 (0.760–0.858) g/kg, respectively. The best-fit prediction equations for SIDC of Lys, Met, Thr and Trp in barley fed to pigs were: SIDC Lys = 0.721 + 0.002 EE (R2 =0.79), SIDC Met = 1.045–0.00041 total starch (R2 =0.69), SIDC Thr = 0.739 + 0.001 ADF (R2 =0.69) and SIDC Trp = 1.468–0.006 CP - 0.001 neutral detergent fiber (R2 =0.99), respectively. The study confirms the large variations in chemical composition of different sources of barley, which contributes to the differences of DE, ME and SIDC of AA in barley fed to pigs and the fiber fraction can be used as key predictors.

Effects of broiler chicken age and dietary protease on the standardised ileal digestibility of amino acids in seeds from two lupin species

Abstract The extent to which lupin seeds can replace soybean meal in diets for broiler chickens is limited, and one of the reasons for this may be a lack of careful consideration given to the age-related amino acid availability differences in the feed formulation process. This study aimed to determine and compare standardised ileal digestibility (SID) coefficients of amino acids (AA) in raw seeds of the Lupinus luteus (YL) and the Lupinus angustifolius (NLL) cultivars as sole sources of AA in the diet of broiler chickens aged 14 or 28 days. An additional purpose was to check the influence of exogenous mono-component protease added to lupin-based assay diets on AA SID in birds at both ages. Each assay diet was offered to six replicatecages. On both sampling days, the contents from the lower half of the ileum were collected for determination of the apparent digestibility values. The SID coefficients were calculated using the age-appropriate basal ileal endogenous AA losses determined from birds fed a N-free diet. Results indicated a substantial advantage of YL over the NLL in SID of Met, Cys, His, Leu, Gly, Asp, Glu, Pro, Tyr and the average of total AA for 14-d-old chickens. With the exception of Cys and Tyr, there was no significant difference between these Lupinus species in the SID of AA in 28-d-old birds. The significant age-related differences within species were found only for the seeds of NLL, where the higher SID for Met, His, Ala, Pro, and the averages of total and indispensable AA were noted in birds aged 28 d. The protease increased SID of most AA from L. luteus in older broilers, whereas for L. angustifolius its efficacy was more pronounced in younger birds, giving the SID values similar to those determined at 28 d on an enzyme-unsupplemented diet. In conclusion, the SID coefficients of indispensable AA determined at 14 or 28 days of age for yellow lupin should not be applied to the precise formulation of starter-type feeds containing seeds of NLL.

166 A Comparison of key Methodologies Used to Quantify Protein Quality in Mammals: Ileal Digestibility, Indicator Amino Acid Oxidation, and in Vitro Digestibility

Abstract There are several methodologies which can be used to measure protein quality of an ingredient, however, the results of these studies are generally not compared to one another. The objectives of these studies were to 1) determine standardized ileal digestibility (SID) and in vitro digestibility coefficients for protein and amino acids (AA) from select pulses; 2) determine metabolic availability (MA) of methionine (Met) from field peas and faba beans; and, 3) compare digestibility coefficients determined via different methods. To determine SID of pulses, ileal cannulated barrows were randomly assigned to diets in a 4×4 Latin square. A nitrogen free diet was used to measure basal endogenous losses of AA and protein. Metabolic availability was determined via indicator AA oxidation by applying the principle of slope-ratio assay to F13CO2 from phenylalanine oxidation quantified through CO2 collection during breath collection using indirect calorimetry with barrows randomly assigned to diets in a 10×10 Latin square. Dietary treatments were formulated to include graded levels of Met: crystalline AA diets (Met inclusion of 50, 60, 70, and 80% of requirement), and pulse test diets (Met inclusion of 60, 70, and 80% of requirement). In vitro digestibility of diets was conducted using the TNO-gastrointestinal model. Statistical analysis of SID data was conducted using a mixed model in SAS with diet as a fixed effect and pig and period as random effects. Means were separated using Tukey HSD. Statistical comparison for digestibility coefficients compared to one another and compared to MA coefficients of Met will be conducted once all IAAO and in vitro data are finalized. The SID coefficients for protein and indispensable amino acids are summarized in Table 1. Peas had lower threonine content compared to faba beans and lentils (P &amp;lt; 0.05). Determination of in vitrodigestibility and MA of Met is in progress.

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.

An investigation into the influence of age on the standardized amino acid digestibility of wheat and sorghum in broilers

Standardized ileal digestibility coefficients (SIDC) of nitrogen (N) and amino acids (AA) in wheat and sorghum at 6 different ages (d 7, 14, 21, 28, 35, and 42) of broilers were determined. Two assay diets were formulated to contain 93.8% of each grain as the sole source of AA in the diet. Titanium dioxide (0.5%) was added as an indigestible marker. Each assay diet was fed to 6 replicate cages housing 14 (d 7), 12 (d 14), 10 (d 21), 8 (d 28), 8 (d 35), and 6 (d 42) birds per cage for 4 d prior to ileal digesta collection. The apparent ileal digestibility coefficients (AIDC) were standardized by using the age-appropriate basal endogenous AA losses. In the case of wheat, AIDC of N and all AA increased (linear or quadratic, P < 0.05 to 0.001) with advancing age. No age effect was noticed on the SIDC of N, average of indispensable (IAA) and dispensable AA (DAA), though the average of total AA (TAA) tended (linear, P = 0.09) to increase as birds grew older. In sorghum, the AIDC of N, average of IAA and DAA were unaffected (P > 0.05) by age. The SIDC of N, average SIDC of IAA, DAA and TAA were higher at d 7, reduced at d 14 and then plateaued. Among the IAA, the SIDC of Arg, His, Ile, Leu, Lys, Thr, Val, and the SIDC of all individual DAA (except Cys) decreased with age (linear or quadratic, P < 0.05 to 0.001) with higher values at d 7. The higher SIDC values determined at d 7 were due to higher EAA losses during wk 1. The results showed that broiler age influences AA digestibility and this may need be considered in practical feed formulations. The age effect is variable depending on the grain type and specific AA.

PSVI-4 Digestible and metabolizable energy content, and standardized ileal digestibility of amino acids in novel corn co-products for swine

Abstract The objective of this study was to determine and compare the digestible energy (DE) and metabolizable energy (ME) content, and standardized ileal digestibility (SID) of amino acids in novel corn co-products and dried distillers’ grains with solubles (DDGS) for swine. Seven corn co-products were evaluated including 2 conventional DDGS (DDGS-A and DDGS-B), 1 corn fiber and solubles (CFS), 2 high protein distillers’ grains (HPDG-A and HPDG-B), and 2 high yeast and protein co-products (HYP-A and HYP-B). In Exp.1, 32 barrows (BW = 24.2 ± 3.4 kg) were housed individually in metabolism crates and randomly allotted to a corn-soybean meal basal diet or 1 of 7 diets containing 30% of a co-product in a randomized two-period crossover design. Feces and urine were collected in 2 periods (7-d adaptation and 4-d collection). In Exp.2, 16 ileal-cannulated barrows (BW = 37.0 ± 3.8 kg) were assigned to 1 of 8 diets in a repeated 8 × 4 Youden square design. An N-free diet, and 7 test diets containing 1 of 7 corn co-products as the sole protein source were used. Diets were fed to pigs for four 7-d periods (5-d adaptation and 2-d ileal digesta collection). The HYP-A and HYP-B had the greatest (P &amp;lt; 0.05) DE (4,309 and 4,183 kcal/kg DM, respectively) and ME (4,118 and 3,972 kcal/kg DM, respectively), and HPDG-B had the lowest (P &amp;lt; 0.05) DE and ME (2,266 and 2,168 kcal/kg DM, respectively) among all corn co-products. The SID of Arg, His, Ile, Lys, Met, Thr, and Val were similar among DGS-B, HPDG-A, HYP-A, and HYP-B, while HPDG-B had the lowest (P &amp;lt; 0.05) SID coefficients for all AA and CP. The high ME and SID Lys, Met, Thr, and Trp content of HYP-A and HYP-B indicate greater feeding value for swine compared to other co-products evaluated.

Standardised Ileal Amino Acid Digestibility in Field Pea Seeds of Two Cultivars Differing in Flower Colour for Broiler Chickens: Effects of Bird Age and Microbial Protease.

Simple SummaryThe extent to which field peas can replace soybean meal in diets for broiler chickens is limited, and one of the reasons for this may be a lack of careful consideration given to the age-related amino acid availability differences in feed formulations. As the digestibility of amino acids in feeds for poultry is a sensitive gauge of their bioavailability, this study has determined and compared standardised ileal amino acid digestibility estimates for whole (raw) seeds of white- and coloured-flowered pea cultivars fed to young and older chickens (14 or 28 days old) in the presence or absence of exogenous protease in their diet. The results demonstrate that when a digestible amino acid system is used, the coefficients of essential amino acids determined at 14 days of age in low-tannin white-flowered peas are not applicable to the formulation of grower-type feed mixtures containing seeds of coloured-flowered cultivars. The increased digestibility of nutritionally essential amino acids in white-flowered pea fed to bids at both ages and in coloured-flowered pea fed to chickens aged 28 days can be expected from protease supplementation. These results contribute to improved use of peas as an alternative to soybean meal vegetable protein sources in diets for broiler chickens.This study aimed to determine and compare standardised ileal digestibility (SID) coefficients of amino acids (AA) in raw seeds of the white-(WF) and the coloured-flowered (CF) field pea cultivar as sole sources of AA in the diets fed to broiler chickens aged 14 or 28 days. An additional purpose was to check the influence of exogenous protease added to pea-based assay diets on AA SID in birds at both ages. Each assay diet was offered to six replicate pens. On both sampling days, the contents from the lower half of the ileum were collected for determination of the apparent digestibility values. The SID coefficients were calculated using ileal endogenous AA losses determined from birds fed an N-free diet. Results indicated a substantial advantage of WF pea over CF pea as a source of digestible Lys, Met, Cys, His, Ile, Leu, Phe, Val, Asp and Glu for 14-day-old chickens. With the exception of methionine and cysteine, there was no significant difference between these two cultivars in the SID values of AA in 28-day-old birds. The protease increased SID of nutritionally essential AA from WF pea-based diet at both ages, and from CF pea-based diet in chickens aged 28 days. In conclusion, the SID coefficients of indispensable AA determined at 14 days of age in low-tannin WF peas are not applicable to the formulation of grower-type feeds containing seeds of CF cultivars.

Influence of feed form on the standardised ileal amino acid digestibility of common grains for broiler chickens

The present experiment was carried out to determine the influence of feed form (FF) on the apparent ileal digestibility coefficients (AIDC) of dry matter (DM), starch and, standardised ileal digestibility coefficients (SIDC) of nitrogen (N) and amino acids (AA) in different grain types (GT). Eight experimental diets were developed in a 4 × 2 factorial arrangement of treatments that included four GT (maize, sorghum, wheat and barley) and two FF (mash vs. pellet). A N-free diet was also used to determine the endogenous N and AA losses for the calculation of SIDC values. Titanium dioxide was incorporated in all diets as an indigestible marker. Ileal nutrient digestibility was determined using the direct method. The four assay diets were formulated to contain 938 g/kg grain as the sole source of AA and starch in the diet. The assay diets and N-free diet were randomly allotted to six replicate cages (eight birds per cage) and fed from 19 to 23 d post-hatch and the ileal digesta was collected on d 23. Pelleting reduced (P < 0.05) the AIDC of DM in all test grains. A significant (P < 0.001) GT × FF interaction was observed for AIDC of starch. Starch digestibility was unaffected by FF in maize- and sorghum-based diets but was reduced in pelleted wheat- and barley-based diets. The GT had a significant (P < 0.05 to 0.001) effect on the SIDC of N and AA. In general, the average values for SIDC of AA were higher in maize followed by sorghum or wheat and barley. The FF showed no significant (P> 0.05) effect on the SIDC of N and AA except cysteine and proline, in which the SIDC values were higher (P < 0.05) in mash than the pelleted diets. Overall, the present data suggest that the physical form of the feed can impact the digestibility of DM, starch and AA in broilers. Because the FF effect on nutrient digestibility can vary depending on the grain type and nutrient, the FF effect should be taken into account in feed evaluation assays to achieve the optimum use of nutrients especially AA.

Nutritional value of Tenebrio molitor larvae meal for broiler chickens: metabolizable energy and standardized ileal amino acid digestibility

Summary Two experiments were conducted to determine the nitrogen-corrected apparent metabolizable energy (AMEn) (experiment 1) and the standardized ileal digestibility coefficients (SIDC) of amino acids (AA) (experiment 2) of Tenebrio molitor larvae meal (TM) for broilers. In experiment 1, 48 21-day-old male broilers were distributed in a completely randomized experimental design with 2 treatments (diets) and 6 replicates (metabolic cages)/treatment, with 4 birds each. Based on the total excreta collection method, cages were randomly assigned to 2 diets: a reference diet and a test diet prepared by substituting 300 g/kg of the reference diet with TM. Ferric oxide (1%) was added to the diets on the first and last day of excreta collection carried out from day 28 to 32, twice daily. In experiment 2, 120 one-day-old male broiler chicks were distributed in a completely randomized experimental design with 2 treatments (diets) and 6 replicates (pens)/treatment, with 10 birds each. At day 16, birds were assigned to 2 experimental diets: a semi-purified nitrogen free diet and a test diet with TM as the sole source of AA, formulated to be approximately 20% CP. Chromium oxide was used at 5 g/kg as an indigestible marker. On day 22, all birds were euthanized, and the contents of the distal ileum were collected. The determined AMEn for TM was 5,004 ± 121.2 kcal/kg DM, a value higher than that of common feed sources of animal and vegetable origin. The average SIDC of AA was 0.86, indicating a good availability of the nutrients for chickens. The values obtained for AMEn and SIDC of TM are comparable to those of other insect meals reported in the literature. Thus, AMEn and SIDC of AA of TM determined here might be applied as a guide to optimize poultry feed formulation using this ingredient.

Energy values and standardized ileal digestibility of amino acids in some feedstuffs for broilers

The objective of this study was to determine the energy values, standardized ileal digestibility coefficients and digestible amino acid contents of parboiled brown rice bran (PBRB), protein sorghum meal (PSM) and bread waste meal (BWM) in broiler diets. In the first trial, 144 broiler chicks at 14 days of age were evaluated in a completely randomized design involving three feedstuffs + a control diet, with six replicates and six birds per experimental unit. The total excreta collection method was adopted to determine the energy values of the feedstuffs. In the second trial, 144 broilers at 24 days of age were used in a completely randomized design involving three feedstuffs + a protein-free diet, with six replicates and six birds per experimental unit. Ileal digesta was harvested to determine the standardized ileal digestibility coefficients and digestible amino acid contents of the feedstuffs. The nitrogen-corrected apparent metabolizable energy (AMEn) values of PBRB, PSM and BWM were 2638, 2799 and 3399 kcal.kg-1, respectively. The metabolizability coefficients of AMEn (CAMEn) of PBRB, PSM and BWM were 54.13, 57.35 and 86.66%, respectively. Bread waste meal had the highest CAMEn (p &lt; 0.05) and standardized ileal digestibility of amino acids (p &lt; 0.01), followed by PBRB and PSM. The main limiting digestible amino acids in PBRB, PSM and BWM were found at the following respective levels: methionine - 0.19, 0.33 and 0.24%; lysine - 0.40, 0.46 and 0.40%; threonine - 0.25, 0.50 and 0.45%; and valine - 0.44, 0.73 and 0.48%.

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.

Nutritional value of enzyme-treated soybean meal, concentrated degossypolized cottonseed protein, dried porcine solubles and fish meal for 10- to -20 kg pigs

The digestible energy (DE) and metabolizable energy (ME) content (Exp.1), and apparent or standardized ileal digestibility coefficients (AIDC or SIDC) of crude protein (CP) and amino acid (AA) (Exp.2) in Soyppt-50% (S50), Hamlet Protein 300, (HP300), concentrated degossypolized cottonseed protein (CDCP), Palbio 50 RD (P50) and fish meal fed to piglets were estimated. In Exp.1, 36 barrows (10.19 ± 1.35 kg BW) were randomly divided into 6 diets with 6 pigs per diet. A basal diet and 5 diets containing 800 g/kg basal diet and 200 g/kg of each test protein ingredient were prepared. In Exp.2, 38 barrows (12.61 ± 1.45 kg BW) were randomly allotted to 1 of 6 diets with 6 pigs except for N-free diet (n = 8). 5 diets containing each of test protein ingredient as the sole source of AA and a N-free diet were formulated. At the end of the trial, ileal digesta of each pig was collected using the slaughter method. Results indicated that S50 contained more DE (16.28 MJ/kg) (P < 0.05) than CDCP (15.79 MJ/kg) and P50 (15.16 MJ/kg), but less (P < 0.05) than HP300 (16.53 MJ/kg) and fish meal (16.59 MJ/kg). The ME content in CDCP (14.68 MJ/kg) was less (P < 0.05) than in S50 (14.47 MJ/kg), HP300 (15.77 MJ/kg) and fish meal (15.63 MJ/kg), but greater (P < 0.05) than in P50 (13.11 MJ/kg). P50 had lower (P < 0.05) AIDC or SIDC of CP and most indispensable AA compared with other protein ingredients. AIDC or SIDC of CP and most indispensable AA in HP300 and CDCP were no differences, but greater (P < 0.05) than in other protein ingredients. S50 and fish meal had similar AIDC or SIDC of CP and most indispensable AA. In summary, S50, HP300 and CDCP had promising potential to replace fish meal in piglet diet after adding appropriate amount of fat and crystalline AA.

Metabolizable energy and amino acid digestibility of mash and pelleted diets for broilers determined under different methodologies

The objective of this study was to determine the interaction between feed processing and different methodologies for assessing apparent metabolizable energy corrected by nitrogen (AMEn) and standardized ileal digestibility coefficients (SIDC) of amino acids (AA) in broiler diets. A completely randomized design in a 4×2 factorial was used to evaluate AMEn by four methodologies and two physical forms of diet (mash and pelleted). The methodologies were total excreta collection and use of the markers: acid insoluble ash (AIA), titanium dioxide (TiO2) and chromium oxide (Cr2O3). After 5days of total excreta collection, all the birds were slaughtered and ileal content was assessed for AA. There was significant interaction (P<0.05) between the methodologies and physical form of the diets on AMEn values. Regardless of the physical form of the diet, the AIA marker provided similar AMEn values for total excreta collection on a DM basis. Pelleted diets had higher values (P<0.05) of AMEn (MJ/kg) on DM, except for Cr2O3. For AA, there was no interaction (P>0.05) between the markers and the physical form of the diets. There was no difference in SIDC between mash and pelleted diets (P>0.05). The AIA marker provided a higher SIDC compared to the TiO2 and Cr2O3 markers, except as regards methionine and lysine. Overall, pelleting increases dietary AMEn, but does not affect amino acid digestibility. Total collection and AIA lead to similar AMEn values, and AIA provides higher SIDC of the amino acids.

Standardized ileal digestibility of amino acids in European soya bean and rapeseed products fed to growing pigs.

This study was conducted to determine the chemical composition and standardized ileal digestibility coefficients (SID) of crude protein (CP) and amino acids (AA) of European soya bean and rapeseed products in pigs. Six soya bean and two rapeseed products were used as the sole dietary source of CP and AA, including raw (FFSB) and roasted full-fat soya beans (FFSBRoasted ), soya bean (SBC) and rapeseed cake (RSC), and rapeseed meal (RSM) from Bavaria (Germany), soya bean meal (SBM) from the Danube region (Austria; SBMAustria ), a commercially available standard SBM (SBMStd ) and an imported genetically modified organism-free SBM (SBMGMO-free ). Eight ileal- cannulated pigs with an initial body weight of 32±2kg were allotted to a row-column design with eight diets and six periods of seven days each. Trypsin inhibitor activity (TIA) ranged from 1.8 in SBMStd to 24.5mg/g DM in FFSB. The SID of CP and all AA in FFSBRoasted were greater than in FFSB, but lower when compared to SBC and SBMAustria (p<.05). The SID of CP and all AA (except glutamic acid) were not different between SBC and SBMAustria , but the SID of CP and all AA (except methionine) were greater (p<.05) in SBC than in SBMGMO-free . Furthermore, the SID of CP and most AA showed a quadratic response with decreasing TIA, and there exists a quadratic response in SID of CP and all AA with increasing lysine to CP ratio and neutral detergent insoluble nitrogen (p<.05). In conclusion, variation in chemical composition and SID of CP and AA was observed in different European soya bean and rapeseed products as influenced by differences in processing conditions. European SBC and SBMAustria can be used as alternative to imported SBMGMO-free and SBMStd in diets for growing pigs.

Basal endogenous losses of amino acids in protein nutrition research for swine and poultry

In this review, the definition and terminology of amino acid (AA) digestibility and ileal endogenous losses of AA (IAAend) in poultry and swine nutrition are discussed. Compared with apparent (AID) and true (TID) ileal digestibility, standardised ileal digestibility (SID) of AA is recommended for the expression of digestible AA contents of feed ingredients and for describing nutritional requirements of poultry and swine. To determine the SID of AA, total ileal flow of AA should be corrected for basal IAAend. Therefore, the measurement of basal IAAend is of great importance for the accuracy of the SID estimation in feed ingredients. The techniques for measuring basal IAAend in poultry and swine include the use of a nitrogen-free diet (NFD), a highly digestible or enzyme hydrolyzed protein diet, and the regression method. The classic method for basal IAAend determination involves the feeding of a NFD to experimental animals and measuring the ileal AA flow. This IAAend output is considered as basal IAAend, and it is assumed that the excretion of basal IAAend depends only on DM intake, regardless of dietary composition. There are criticisms with the NFD method about the abnormal physiological state induced by severe AA deficiency. Although this AA deficiency may affect the estimate of basal IAAend for dispensable AA, especially proline and glycine because of the degradation of body protein, the NFD method is still the most widely used method for basal IAAend measurements. According to the definition of basal IAAend, the NFD should be the preferred methodology in SID determination, because the basal IAAend should be only related to dry matter intake. Additionally, the SID coefficients in feed ingredients generated by NFD method are considered to be additive in a complete diet. However, the results generated from NFD method can vary among studies due to the variance in the experimental animals and diet composition. To improve the accuracy of estimating the SID of AA in feed ingredients, it is suggested that a mandatory NFD be included in individual studies to generate basal IAAend for correcting total ileal amino acid flow in determining SID of AA. In addition, research is needed to investigate the standard diet formulation of NFD.

Effects of Increasing Crystalline Amino Acids in Sorghum- or Corn-based Diets on Finishing Pig Growth Performance and Carcass Composition

A study was conducted to determine the impact of increasing crystalline amino acids in either sorghum- or corn-based diets on finishing pig growth and carcass composition. A total of 288 pigs (PIC 327×1050; initially 101.1 lb) were used in a 90-d study with 8 pigs per pen and 6 pens per treatment. Treatments were arranged in a 2 × 3 factorial with main effects of grain source (sorghum vs. corn) and crystalline AA supplementation (low, medium, or high). Amino acids ratios to Lys as well as standardized ileal digestibility coefficients used were set by NRC (2012). All diets were formulated to the same Lys:NE ratio and at 95% of the pig’s estimated Lys requirement to ensure that AA were not above the pigs’ requirement. The grain sources and soybean meal were analyzed for AA profile and diets formulated from these concentrations. The low AA fortification contained L-lysine HCl and DL-methionine. The medium AA fortification contained L-lysine HCl, DL-methionine, and L-threonine. The high AA fortification contained L-lysine HCl, DL-methionine, L-threonine, and L-valine in sorghumor L-tryptophan in corn-based diets. Overall, there were no grain source × crystalline AA level interactions observed for any response criteria measured. Pigs fed corn-based diets tended to have greater ADG (P < 0.072) and had better F/G (P < 0.01) than those fed sorghum-based diets. As crystalline AA increased, ADG tended to increase then decrease (quadratic; P=0.057), and ADFI decreased (linear; P = 0.019) resulting in a tendency for improved F/G (quadratic; P=0.097). Pigs fed sorghum had decreased (P < 0.01) jowl fat iodine value in comparison to those fed corn-based diets. Crystalline AA level did not impact carcass characteristics. In conclusion, diets with high AA fortification had decreased ADG and ADFI with slightly improved F/G compared with low or medium AA fortification. Furthermore, grain sorghum had approximately 97% of the feeding value relative to corn based on F/G.

Effects of increasing crystalline amino acids in sorghum- or corn-based diets on nursery pig growth performance (2014)

A total of 300 pigs (PIC 1050; initially 23.3 lb BW) were used in a 21-d study to compare the effects of increasing crystalline amino acids in sorghum- and corn-based diets on nursery pig growth performance. Treatments with 5 pigs per pen and 10 pens per treatment were arranged in a 2 × 3 factorial with main effects of grain source (sorghum vs. corn) and crystalline amino acid supplementation (low, medium, or high). Amino acid ratios to lysine as well as standardized ileal digestibility coefficients used were set by NRC (20123). Because replacing increasing amounts of soybean meal with crystalline amino acids changes the NE of the diet, all diets were formulated to the same Lys:NE ratio. The lysine concentration in the diets was formulated at 95% of the pig’s estimated requirement to ensure that the other amino acids, on a ratio to lysine, would not be underestimated. The grain sources and soybean meal were analyzed for amino acid profile and diets formulated from these concentrations. The low amino acid fortification contained L-lysine HCl and DL-methionine. The medium amino acid fortification contained L-lysine HCl, DL-methionine, and L-threonine, and the high amino acid fortification contained L-lysine HCl, DL-methionine, L-threonine, and L-valine. Overall, no main or interactive effects (P > 0.05) of grain source or added amino acids were detected for any response criteria. This suggests that balancing to the third, fourth, or fifth limiting amino acids is possible in both sorghum- and corn-based diets with the use of crystalline amino acids without detrimental effects on growth performance.; Swine Day, Manhattan, KS, November 20, 2014

Evaluation through literature data on standardized ileal digestibility and basal ileal endogenous loss of amino acids associated with barley in pigs

This meta-analysis aimed to estimate the standardized ileal digestibility (SID) and the basal ileal endogenous amino acid losses (IAAend) in barley for growing pigs. In total, 38 different barley treatments published in 26 peer-reviewed papers were used for the meta-analysis containing information on dietary composition including amino acid (AA) contents of the assay diets, and (or) barley samples, as well as apparent ileal digestibility (AID) of AA in barley. The SID of AA was determined by either correcting AID of AA for their IAAend or by regression analysis between the apparent ileal digestible and total dietary AA contents. The SID values obtained by correcting the AID values for their IAAend amounted to 70%, 77%, 74% and 63% for Lys, Met, Thr and Trp, whereas those based on regression analysis method were 82%, 82%, 69% and 55%, respectively. Estimates of basal ileal endogenous loss of CP in ileal digesta varied considerably and averaged 11.84 g/kg dry matter intake (DMI), whereas IAAend for indispensable AA ranged from 0.05 g/kg DMI for Trp to 1.90 g/kg DMI for Leu. In most cases, these estimates were considerably higher than previously reported values for IAAend. The results of the present regression analysis indicate for most AA higher SID values compared with SID of most AA that were obtained by correcting AID values for IAAend. In view of the observed high variations in IAAend and the low CP content of the barley samples, estimating SID of AA based on literature data by means of the regression method may improve accuracy of SID coefficients for barley. In contrast, transformation of AID values into their corresponding SID values by using a constant correction factor for IAAend adds an additional source of error, thereby reducing the precision in estimating SID of AA.