Digestible Indispensable Amino Acid Research Articles

Digestible indispensable amino acid score (DIAAS) and protein digestibility corrected amino acid score (PDCAAS) in oat protein concentrate measured in 20- to 30-kilogram pigs.

Oat protein concentrate is often used in human food, but the quality of this protein has not been characterized. Therefore, the objectives of this experiment were to determine the standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) in oat protein concentrate and to determine differences in protein quality estimates between the protein digestibility-corrected AA score (PDCAAS) and the digestible indispensable AA score (DIAAS) when using growing pigs for both measurements. For infants, the most limiting AA in oat protein concentrate was the aromatic AA (Phe + Tyr), for which the DIAAS value was 41 and the PDCAAS was 43. For children (6 months to 3 years) and children older than 3 years, the most limiting AA in oat protein concentrate was Lys, for which the DIAAS was 56 and 67 and the PDCAAS was 58 and 69, respectively. The DIAAS value for oat protein concentrate was close to the calculated value for PDCAAS, but below the recommended intake for protein. Therefore, to satisfy the daily human AA requirement, oat protein needs to be complemented by other proteins of higher quality and specifically with greater lysine concentrations. © 2017 Society of Chemical Industry.

Herring roe protein has a high digestible indispensable amino acid score (DIAAS) using a dynamic in vitro gastrointestinal model

It is hypothesized that the digestible indispensable amino acid score (DIAAS) can be determined based on dynamic in vitro gastrointestinal digestion experiments as replacement for invasive animal studies. We determined the in vitro DIAAS for immature herring eggs (roe) proteins in comparison with reference proteins. The true ileal digestibility of protein and indispensable amino acids (IAA) was measured under human conditions simulated in a gastrointestinal model (tiny-TIM). The in vitro true ileal digestibility of ovalbumin, cooked and raw chicken egg white, and casein was similar to that found in humans (r2 = 0.96), providing a casual observation to support the validity of tiny-TIM. The digestibility of the immature herring egg proteins was 71% to 92%. The highest IAA digestibility was found for immature whole herring egg protein (55%-80%) in comparison to immature herring egg membrane and immature de-membraned herring protein (50%-70%). The DIAAS as recommended by FAO for children and adults, but measured in vitro, were 91% for immature whole herring egg protein (lysine first limiting), 71% for immature herring egg membrane protein (histidine first limiting), and 88% for immature herring egg de-membraned protein (sulfur AA first limiting). True ileal protein and amino acid digestibility can be determined in a dynamic gastrointestinal model, such as tiny-TIM, which can be used for estimating the DIAAS. Immature herring egg proteins, a previously underutilized resource, were determined to be an important and valuable source of IAA for human consumption.

Interactive effects of a high-quality protein diet and high stocking density on the stress response and some innate immune parameters of Senegalese sole Solea senegalensis

Amino acids (AA) regulate key metabolic pathways, including some immune responses. Therefore, this study aimed to assess whether an increased availability of dietary AA can mitigate the expected increase in plasma cortisol and metabolites levels due to high stocking density and its subsequent immunosuppression. Senegalese sole (Solea senegalensis) were maintained at low stocking density (LSD; 3.5 kg m(-2)) or high stocking density (HSD; 12 kg m(-2)) for 18 days. Additionally, both treatments were fed a control or a high protein (HP) diet (LSD, LSD HP, HSD and HSD HP). The HP diet slightly increased the levels of digestible indispensable AA, together with tyrosine and cysteine. HSD was effective in inducing a chronic stress response after 18 days of treatment since fish held at HSD presented higher plasma cortisol, glucose and lactate levels. Moreover, this increase in stress indicators translated in a decrease in plasma lysozyme, alternative complement pathway (ACP) and peroxidase activities, suggesting some degree of immunosuppression. Interestingly, while plasma glucose and lactate levels in HSD HP specimens decreased to similar values than LSD fish, plasma lysozyme, ACP and peroxidase activities increased, with even higher values than LSD groups for ACP activity. It is suggested that the HP diet may be used as functional feed since it may represent a metabolic advantage during stressful events and may counteract immunosuppression in sole.

Effects of dietary amino acids and repeated handling on stress response and brain monoaminergic neurotransmitters in Senegalese sole ( Solea senegalensis) juveniles

The present study aimed to assess the effects of increased availability of dietary amino acids (AA) on brain monoamine neurotransmitters and the metabolic processes resulting from stressful situations in fish. Senegalese sole ( Solea senegalensis) juveniles (24.2 ± 0.4 g wet mass) were weekly subjected to an acute handling stressor (HDLG) or remained undisturbed (CTL). Additionally, both treatments were fed a control or a high protein (HP) diet (CTL, CTL HP, HDLG and HDLG HP). The HP diet slightly increased the levels of digestible indispensable AA, together with tyrosine and cysteine. Repeated handling induced a stress response after 14 and 28 days in fish held at both HDLG and HDLG HP treatments. While dietary treatment and handling stress activated the serotonergic system at 14 days, these effects were not observed after 28 days. In addition, the HP diet minimized the decrease in plasma indispensable AA due to repeated handling stress after 28 days. It was concluded that HP diet decreased post-stress plasma glucose and lactate levels in HDLG HP specimens only at 14 days of treatment. Moreover, dietary treatment was also effective in stimulating DA synthesis and release, thus dietary phenylalanine supplementation can increase DA biosynthesis in fish.

Protein utilization and amino acid digestibility of canola meal in response to phytase in broiler chickens

The regression method was used in a 14-d broiler chicken study to determine the true ileal digestibility of amino acid (AA) and protein utilization in canola meal (CM, 388 g of CP/kg) without or with added phytase. Experimental treatments consisted of 2 factors, phytase at 2 levels (0 or 1,500 phytase units/kg) and CM at 3 levels (125, 250, or 375 g/kg). Birds received a standard starter diet from d 1 to 8 and the assay diets from d 8 to 22 posthatch. On d 8, a total of 384 birds were allocated to 6 dietary treatments in a randomized complete block design; excreta were collected from d 12 to 14 and d 19 to 21, and ileal digesta were collected on d 22 posthatch. True ileal indispensable AA digestibility of CM were derived from the regression of AA flow (mg/kg of DM intake) at the terminal ileum against the intake of AA (mg/kg of dietary DM) of birds fed diets without or with phytase. Body weight gain (BWG), protein gain, and protein intake increased linearly (P < 0.001) with increasing CM level, regardless of phytase supplementation. Effects of phytase (P < 0.05) were observed on BWG and the protein efficiency ratio from d 8 to 15, whereas effects of phytase (P < 0.05) were observed on BWG and protein gain from d 15 to 22. There was no effect of phytase on protein intake and net protein utilization from d 8 to 22. Phytase supplementation at 1,500 phytase units/kg did not affect true ileal digestibility of any AA in CM. In conclusion, the results of this study indicated that phytase supplementation improved the protein efficiency ratio of birds fed diets containing CM as the sole protein source from d 8 to 15 posthatch but did not affect the true ileal digestibility of AA in CM as determined by the regression method.

The effect of autoclave processing and gamma irradiation on apparent ileal digestibility in broiler breeders of amino acids from canola meal.

The objective of this study was to investigate the effect of different doses of gamma irradiation and autoclaving on the apparent ileal digestibility in male broiler breeders of amino acids from canola meal. Samples were irradiated in a gamma cell at total doses of 15, 30 and 45 kGy. One package (control) was left at a room temperature: similar to the other treatments, evaporation decreased the moisture content of the samples. Autoclaving of canola meal for 15 min at 121°C was studied. The treatments were: 1) control untreated canola meal diet; 2) autoclaved canola meal diet; 3) canola meal diet gamma irradiated at a dose of 15 kGy; 4) canola meal diet gamma irradiated at a dose of 30 kGy; 5) canola meal diet gamma irradiated at a dose of 45 kGy. The results showed that autoclaving for 15 min at 121°C had a statistically significant effect on the apparent ileal digestibility of the amino acids in canola meal (p < 0.05). Autoclaving increased the apparent ileal digestibility of the amino acids of canola meal compared with the other treatments (p < 0.05). The effect of autoclaving on an increase in total coefficient of ileal apparent of amino acid digestibility (CIAD) total apparent ileal digestibility of indispensable amino acids, and total apparent ileal digestibility of dispensable amino acids was significant (p < 0.05). Gamma irradiation at doses of 15, 30 and 45 kGy significantly decreased the content of glucosinolate of canola meal compared with that of untreated canola meal (p < 0.05). The results also showed that gamma irradiation of canola meal were effective in denaturizing of protein and in increasing the apparent digestibility of amino acids. In addition, autoclaving canola meal for 15 min at 121°C and 105 kPa increased the apparent digestibility of amino acids. Irradiation of canola meal at 45 kGy improved the apparent digestibility of amino acids in comparison with the other processing methods. Key words: Gamma, digestibility, protein, canola, poultry.

Evaluation of barley and triticale as feed ingredients in growing Iberian pigs: amino acid and carbohydrate ileal digestibility

AbstractBACKGROUND: Iberian pig production is linked to the use of the Mediterranean woodland, where the use of local feed resources is of paramount importance for the sustainability of the system. The aim of the present work was to explore the potential of triticale cv. Camarma as compared to barley cv. Esgueva in Iberian pig feeding by studying their respective ileal digestibilities of amino acids and carbohydrates in animals cannulated at the end of the ileum.RESULTS: Leu, Met and Tyr had (P &lt; 0.05) greater standardised ileal digestibilities (SID) in pigs fed triticale diet. There was a trend (P = 0.07) towards greater SID of Thr in pigs fed the barley diet. The least digestible indispensable amino acids were Ile (74.6% SID) for barley and Thr (78.9% SID) for triticale. Except for β‐glucans, apparent ileal digestibilities (AIDs) of individual non‐starch polysaccharide (NSP), sugars and starch were greater in pigs fed triticale (P &lt; 0.05). Nevertheless, total amounts of NSP digested were greater in pigs fed the barley diet (P &lt; 0.05).CONCLUSION: Overall, triticale cv. Camarma had greater amino acid and carbohydrate AID than barley cv. Esgueva and may represent a valuable grain for Iberian pig feeding. Copyright © 2008 Society of Chemical Industry

Digestible energy, protein and amino acid content in selected short season corn cultivars fed to growing pigs

The digestible energy (DE), ileal digestible crude protein (CP) and amino acid (AA) contents in two corn cultivars commonly grown in Manitoba were determined using six ileal cannulated barrows (average initial BW of 21.5 ± 0.9 kg). Three samples of each cultivar, each obtained from two locations, were evaluated in six dietary treatments in a 2 × 3 factorial arrangement. Diets contained 97% corn and 0.3% chromic oxide as an indigestible marker, and were assigned to pigs in a 6 × 6 Latin square design. Ileal digesta and fecal samples were collected for determining energy and nutrient digestibilities. Location affected (P ≤ 0.05) ileal digestible indispensable AA, except for lysine and threonine. Cultivar affected (P ≤ 0.05) ileal digestible CP and indispensable AA, except for lysine, phenylalanine and valine. There was an interaction effect (P &lt; 0.05) of location and cultivar on ileal digestible indispensable AA, except for lysine and histidine. Digestible energy, CP and AA averaged 3662 kcal kg-1, 5.95% and 0.40%, respectively, in the dry matter. The content of digestible CP and AA in corn may vary with location and cultivar and this variation should be considered when formulating livestock feeds. Key words: Amino acids, corn, digestibility, energy, pig

Apparent ileal digestibility of amino acids in dietary ingredients for broiler chickens

AbstractThe apparent ileal digestibility coefficients of amino acids in 107 samples representing 22 food ingredients were determined using 6-week-old broiler chickens. The ingredients assayed included five cereals (barley, maize, sorghum, triticale and wheat), two cereal by-products (rice polishings and wheat middlings), four oilseed meals (canola, cottonseed, soya-bean and sunflower meals), full-fat canola, maize gluten meal, four grain legumes (chickpeas, faba beans, field peas and lupins) and five animal protein sources (blood, feather, fish, meat and meat and bone meals). The mean ileal digestibility coefficients of amino acids in wheat and maize were higher than those in sorghum, triticale and barley. However, variations observed in individual amino acid digestibilities among samples within cereal type were greater than those determined between cereals. Threonine and lysine were the least digestible indispensable amino acids in the five cereals evaluated. The most digestible indispensable amino acid was phenylalanine in wheat and, leucine in maize and sorghum. In the case of the wheat middlings and rice polishings, threonine was the least digestible indispensable amino acid and arginine was the best digested.In the oilseed meals assayed, amino acid digestibility was highest for soya-bean and sunflower meals, intermediate for canola meal and lowest for cottonseed meal. Ileal digestibility coefficients of amino acids in lupins were found to be slightly lower than those in soya-bean meal. The amino acid digestibilities of field peas, faba beans and chickpeas were considerably lower than those of lupins. Digestibility of arginine was the highest and that of threonine was the lowest of the indispensable amino acids in oilseed meals and grain legumes, except in cottonseed meal. Lysine was the least digestible amino acid in cottonseed meal.In the animal protein sources assayed, digestibility coefficients of amino acids in blood meal were high, intermediate in fish meal, and low in meat meal, meat and bone meal and feather meal. Variation in amino acid digestibility coefficients determined for blood meal samples was small. However, wide variations in amino acid digestibilities were observed for other animal protein sources, highlighting significant batch-to-batch differences. In particular, marked variations were determined for meat meal and meat and bone meal samples. Cystine was the least digested amino acid in animal protein meals, with the exception of blood meal in which isoleucine had the lowest digestibility. The limitations of using apparent digestibility values in diet formulations and the concept of the standardized digestibility system to overcome these limitations are discussed.

Utilization of Energy and Amino Acids of Spray-Dried Egg, Plasma Protein, and Soybean Meal by Ducks

A study was conducted to determine AMEn, TMEn, apparent amino acid digestibility (AAAD), and true amino acid digestibility (TAAD) of spray-dried egg (SDE), plasma protein (PP), and soybean meal (SBM). AMEn and TMEn values for ducks fed SDE were higher (P ≤ 0.001) than for ducks fed PP, which were higher than SBM. The AMEn values were 5.048, 3.230, and 2.605 kcal/g for SDE, PP, and SBM, respectively, with TMEn values of 5.373, 3.555, and 2.930 kcal/g, respectively. Spray-dried egg, PP, and SBM were similar in apparent digestibility of the indispensable amino acids except for methionine, histidine, and valine. Apparent methionine digestibility in SDE (95.5%) was higher (P ≤ 0.01) than PP (88.3%) or SBM (91.3%). Apparent digestibilities of dispensable amino acids were similar for SDE, PP, and SBM except proline and alanine. Apparent alanine digestibility in SDE (89.9%) was higher (P ≤ 0.05) than in SBM (85.7%). True digestibilities of indispensable amino acids were similar in SDE, PP, and SBM except for methionine, histidine, and valine. True methionine digestibility was higher (P ≤ 0.05) for SDE (97.0%) than for PP (89.8%) or SBM (92.7%), with PP and SBM being similar. True histidine and valine digestibilities were significantly lower for SDE (P ≤ 0.05) than for PP or SBM. True digestibilities of the dispensable amino acids were also similar in SDE, PP, and SBM except for proline and alanine. This study demonstrates that the energy value of SDE is greater than that of PP or SBM.

Verwertung der im Intestinum wachsender Bullen absorbierten essentiellen Aminosäuren

Abstract. Title ofthe paper: The efficiency of utilization of intestinal digestible indispensable amino aeids in growing bulls There are problems to determine the efficiency of protein deposition of intestinal absorbed amino aeids, because it cannot be exeluded that the amount of single or some indispensable amino acid (IAA) can influence the growing Performance of the animal. The dependence of amino acid gain on the flux of essential absorbable amino aeids into the duodenum was studied in growing bulls to calculate the utilization rate of these amino aeids. Four growing bulls (Schwarzbuntes Milchrind, BW: 240–310 kg) with duodenal T-type cannulas were fed diets varying in crude protein content. Energy level was 11,2 MJ ME/kg DM. The efficiency for the different absorbable IAA was decreased with increasing nutritional level. This is in contrast with the constant utilization factor ofthe protein evaluation system (AfB, 1995; 1997). The efficiency of utilization of apparently digestible IAA for protein retention was highest for His and Met and amounted to 33 (He), 34 (Phe and Thr), 38 (Lys and Val), 41 (Leu), 52 (Met) und 76 (His) %, respectively. The intersection ofthe regression curve (AA-deposition against apparently digestible AA) with the abscissae resulted in the maintenance requirement of absorbable amino acid. For growing bulls (BW: 300 kg) a value of 4,7 g/d histidine and 4,2 g/d methionine was determined, but more investigations are necessary in this field.

The influence of cecectomy on metabolizable energy and amino acid digestibility of select feedstuffs for white Pekin ducks

Twenty-four cecectomized and 24 intact White Pekin ducks were used in two experiments to assess the influence of cecectomy on ME and amino acid digestibility of several feed ingredients for ducks. Corn and soybean meal (SBM) were evaluated in Experiment 1, and bakery meal (BM), red dog (RD), and wheat middlings (WM) were evaluated in Experiment 2. Nitrogen-corrected true metabolizable energy and amino acid digestibility of the ingredients were assayed concurrently. In Experiment 1, TME of corn was higher (P < or = 0.05) in cecectomized ducks, and intact ducks demonstrated greater (P < or = 0.05) ability to utilize the energy in SBM. Intact ducks exhibited higher (P < or = 0.05) true digestibilities of lysine and methionine. True digestibility of tryptophan was higher (P < or = 0.05) for cecectomized ducks. True digestibility of indispensable amino acids in SBM did not differ (P > or = 0.05) between cecectomized and intact ducks. In Experiment 2, cecectomized ducks exhibited greater (P < or = 0.05) ability to utilize the energy in RD. Intact ducks exhibited greater (P < or = 0.05) ability to utilize the energy in WM. True digestibility of indispensable amino acids in BM, RD, and WM was variable. Results of the present study suggest that the effect of cecectomy on nutrient digestibility in ducks is dependent on the feedstuff assayed.

Effects of Processing on the Nutritional Quality of Canola Meal

Two 10-day chick bioassays and two amino acid digestibility trials using cecectomized cockerels were conducted to assess the effects of steam heating and commercial processing on in vivo protein quality of canola meal. In vitro protein solubility measurements in .2 or .5% KOH were evaluated as predictors of in vivo protein quality. Commercial solvent-extracted canola meal autoclaved at 121 C and 105 kPa (international pressure units) for 0, 10, 20, 30, 40, 60, or 90 min, was fed to 8-day-old chicks in corn-canola meal diets containing 20% CP. Growth performance of chicks fed autoclaved canola meal decreased linearly (P ≤ .001) as autoclaving time increased. The analyzed lysine content in canola meal was reduced markedly by increased autoclaving time, with little or no effects observed for other amino acids. True digestibilities of indispensable amino acids decreased (P ≤ .05) as autoclaving time increased, with lysine providing the most notable change. The decreased digestibility of lysine was due both to reduced concentration of analyzed lysine and to reduced digestibility of the analyzed lysine remaining after autoclaving. Protein solubility in .2 and .5% KOH decreased as autoclaving time increased. Use of .5% KOH provided a larger range in solubility values over autoclaving times. Four samples of canola from different stages of processing (full-fat seeds, flaked or conditioned meal, expeller meal, and solvent-extracted meal) were also evaluated. Protein solubility in .2% KOH decreased upon solvent extraction, but there were no significant changes in amino acid digestibility due to stage of processing.