Essential Amino Acid Requirements Research Articles

140 Response of 6 to 13 kg nursery pigs to increasing SID Arg:Lys

Abstract Newly weaned pigs (n = 480; PIC 337 × 1050; Genus, Hendersonville, TN) with an initial body weight (BW) of 6.20 ± 0.61 kg were used in a dose-response study to evaluate the effects of increasing standardized ileal digestible (SID) Arg:Lys in nursery pigs. At weaning, pigs were placed into 48 pens with five barrows and five gilts per pen and randomly assigned to one of six dietary treatments. The experimental diets were formulated with increasing levels of SID Arg by replacing corn starch, glycine, and L-alanine with L-arginine. Levels of SID Arg:Lys ranged from 45 to 145%. Diets were sub-limiting in SID Lys and exceeded all other essential amino acid requirements. Furthermore, diets were formulated to be isocaloric, isonitrogenous, and met or exceeded NRC (2012) vitamin and mineral recommendations. The experimental diets were fed in two feeding phases from d 0 to 10 and d 10 to 27, with adjustments made to account for the decreasing Lys requirement of the pigs. Pigs were subsequently fed a common diet for the remaining 14 d of the nursery period to determine carryover effects. Pigs and feeders were weighed at the beginning and end of each dietary phase for the calculation of average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (gain to feed ratio; G:F). The data were fit using linear regression with R version 4.3.1 (R Core Team, 2023). The model included linear and quadratic effects of SID Arg:Lys and initial BW. Pen was the experimental unit, and results were considered significant at P ≤ 0.05 and a tendency at 0.05 < P ≤ 0.10. There was a significant linear and quadratic effect of SID Arg:Lys on BW on d 27 (P ≤ 0.024), where BW was maximized at a SID Arg:Lys 97.09%. From d 0 to 27 there was a linear and quadratic tendency of SID Arg:Lys on ADFI (P = 0.069), where feed intake was maximized at a SID Arg:Lys of 97.00%. Furthermore, there tended to be a linear and quadratic effect of SID Arg:Lys on ADG from d0 to 27 (P ≤ 0.081), where ADG was maximized at a SID Arg:Lys of 95.65%. There was no evidence for an effect of SID Arg:Lys on G:F at any timepoint throughout the trial (P ≥ 0.298). In conclusion, SID Arg:Lys linearly and quadratically impacted ADFI and ADG in 6 to 13 kg nursery pigs, where ADG was maximized at a SID Arg:Lys of 95.65%, but ADFI was maximized at a SID Arg:Lys of 97.00%. Together, these data suggest that the SID Arg:Lys requirement of nursery pigs is greater than NRC (2012) recommendations, and excessive Arg supplementation may have negative consequences on growth performance.

Essential amino acid requirements of fish and crustaceans, a meta‐analysis

AbstractA meta‐analysis of literature data on essential amino acid (EAA) requirements of fish and crustaceans was performed to re‐estimate EAA requirements and provide ideal amino acid profiles. Large numbers of studies have been conducted on EAA requirements of fish and crustaceans over the past decades. However, estimated EAA requirements of different species showed a large variation due to differences in methodological approaches and regression models. An extensive search and inclusion of literature on EAA requirements were conducted following the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidelines in this study, resulting in a dataset of 358 studies covering 77 species. The relative percentage of maximum weight gain was used as the outcome to evaluate the 10 EAA requirements. Forest plots analysis was employed for heterogeneity analysis, study weight allocation and re‐estimation of the requirements. Results showed that trophic level, water temperature and dietary EAA inclusion levels affected EAA requirements estimation. The meta‐analysis suggested that the estimated 10 EAA requirements (expressed as % crude protein, CP) of the fish were: arginine (Arg) 5.0 (±0.14), histidine (His) 2.0 (±0.11), isoleucine (Ile) 3.3 (±0.16), leucine (Leu) 4.9 (±0.24), valine (Val) 3.8 (±0.11), lysine (Lys) 5.2 (±0.12), sulfur amino acids (Met + Cys) 3.5 (±0.18), total aromatic amino acids (Phe + Tyr) 6.2 (±0.12), threonine (Thr) 3.5 (±0.18) and tryptophan (Trp) 0.9 (±0.08). Estimated EAA requirements (expressed as % CP) of crustaceans were Arg 5.1 (±0.31), His 2.5 (±0.15), Ile 4.3 (±0.97), Leu 5.7 (±0.08), Val 4.3 (±0.30), Lys 4.9 (±0.28), Met + Cys 3.2 (±0.18), Phe + Tyr 5.1 (±0.65), Thr 3.8 (±0.04) and Trp 0.8 (±0.15).

The potential of young vegetative quinoa (Chenopodium quinoa) as a new sustainable protein-rich winter leafy crop under Mediterranean climate

The demand for protein products has significantly risen in the last few years. In western countries, animals are the primary source of protein; however, plants could take a share of this market due to lower production costs, among other advantages such as a lower environmental footprint. Quinoa (Chenopodium quinoa Willd.) is a well-known but under-utilized protein-rich crop, commonly cultivated for grain production. These plants were recently evaluated for their use as a non-traditional, green leafy crop. Here we assessed the potential of young vegetative quinoa as a new sustainable winter leafy crop in Israel—serving as a model for Mediterranean semi-arid regions, by evaluating yield, protein content and quality. Five quinoa accessions were sown on three winter sowing dates over two consecutive years. Plants were harvested when they reached 10% dry matter (DM). DM yield ranged between 574 and 1,982 kg ha-1 and was generally higher in the second year. Protein content ranged from 14.4–34% and was generally higher in the first year. Protein yield ranged from 111–471 kg ha-1 and was greatest on the December sowing date. DM and protein yields were positively correlated with plant density. Protein content was negatively correlated with plant density and DM yield. Our findings show that 200 g DM of young vegetative quinoa can meet the protein and most essential amino acid requirements for a 70 kg human adult. Prospects for cultivating young vegetative quinoa in Mediterranean countries as a new sustainable, protein-rich winter leafy crop are therefore high, as supported by its high protein yields and quality, and its requirement for only scant irrigation. Further studies should examine economic and other agrotechnical parameters toward the geographical distribution and expansion of young vegetative quinoa cultivation.

48 Evaluation of Branched-Chain Amino Acid Interactions in 13 to 23 kg Nursery Pigs Using a Central Composite Design

Abstract Two groups of 240 pigs (PIC 337 X 1050, PIC Genus, Hendersonville, TN) with initial body weight (BW) 13.20 ± 3.05 kg were used to investigate interactions between the branched-chain amino acids (BCAA). At weaning, pigs were placed into 40 pens with three barrows and three gilts per pen and fed a common diet for 3 weeks. On day 21 post-weaning, pens were randomly assigned to 1 of 15 dietary treatments arranged in a rotatable central composite design. Experimental diets were formulated to various levels of standardized ileal digestible (SID) leucine, isoleucine, and valine by replacing corn starch and glycine with L-leucine, L-isoleucine, and L-valine in the base diet. Levels of BCAA were expressed as ratios to SID lysine and ranged from 98 to 180 for Leu, 46 to 64 for Ile, and 51 to 78 for Val. Diets were formulated to be sub-limiting in lysine at 1.19% SID Lys and exceed all other essential amino acid requirements. Additionally, diets were formulated to be isocaloric and isonitrogenous and met or exceeded NRC (2012) vitamin and mineral requirements. Pen weights and feed intake were measured for the 21-day experiment to calculate daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (G:F). Data were fit as a second-order response surface model according to the central composite design in R version 4.2.1 (R Core Team, 2022). The model included linear and quadratic effects of Leu, Ile, and Val, and their cross-products. Pen was the experimental unit, and variables were considered significant at P ≤ 0.10. Valine linearly and quadratically impacted ADG and G:F, regardless of Leu and Ile levels. There was an interaction between Leu and Ile for ADG (P = 0.079) and G:F (P = 0.031), where, at increasing levels of Leu, decreasing Ile improved ADG and G:F. Conversely, ADG and G:F decreased as both Leu and Ile increased. Isoleucine did not impact ADFI (P ≥ 0.458); however, there was an interaction between Leu and Val (P = 0.088), where Leu negatively impacted ADFI at low levels of Val, but did not influence ADFI at greater levels of Val. In conclusion, the response of nursery pig ADG and G:F to Val is independent of Leu and Ile levels, while ADG and G:F are reduced at greater levels of Leu and Ile, which is resolved as either Leu or Ile are reduced. Furthermore, at deficient levels of Val, ADFI is negatively impacted by increased Leu; however, the negative impacts of increasing Leu on ADFI are negated when Val is adequate or above requirement. This experiment emphasizes the complexity of amino acid metabolism in nursery pigs and the importance of understanding potential interactions among amino acids when conducting research.

PSII-11 Supplementation of Non-Protein Nitrogen to a Nitrogen-Deficient Diet Increases Lysine Requirement for Nitrogen-Retention

Abstract Low protein (LP) diets have improved nutrient utilization while maintaining animal performance. Regardless, these diets may be limiting in nitrogen (N) content to meet non-essential amino acid (NEAA) requirements, potentially altering essential amino acid (EAA) utilization and requirements. Inclusion of a non-protein nitrogen (NPN) may be beneficial for improving utilization of EAA in LP diets. The objective of this study was to determine the impact of NPN in an N-deficient diet, as indicated by EAA-N:total N ratio (EAA-N:TN) on the Lys requirement for nitrogen retention (NR). A total of 90 growing barrows (initial BW of 20.4 ± 0.46 kg) were randomly assigned to 1 of 10 dietary treatments (n = 9 pigs/treatment) in 9 blocks in a 2 × 5 factorial design. Diets contained no ammonium phosphate (NAP; EAA-N:TN of 0.56) or were supplemented with 1.7% ammonium phosphate (AP; EAA-N:TN of 0.50) with graded levels of dietary lysine [Lys; 0.8%, 0.9%, 1.0%, 1.1% and 1.2% standardized ileal digestible (SID)]. Diets were corn and soybean meal-based and formulated to meet or exceed nutrient requirements according to NRC (2012). Diets were fed at 2.8 × maintenance metabolizable energy requirements in two equal meals per day. A 4-d nitrogen balance collection period was conducted following a 7-d dietary adaptation period. Urine was collected quantitatively, and fresh fecal samples were obtained daily. Nitrogen retention was determined as the difference between N intake and output (fecal and urinary). Linear breakpoint modeling with PROC NLIN was used to estimate Lys requirement. Nitrogen retention was optimized at 1.00% SID Lys (15.6 g/d NR; R2 = 0.68) in pigs fed NAP diets and 1.09% SID Lys (16.4 g/d NR; R2 = 0.61) in pigs fed AP diets. Overall, deficient dietary N reduced NR and Lys requirement, which were increased with NPN supplementation.

209 Lowering Dietary Crude Protein Concentration Decreases Nitrogen Excretion and pH of Urine and Slurry in 15-kg Nursery Pigs

Abstract The objective of the present work was to determine the effects of reucing dietary crude protein (CP) concentrations with essential amino acid (EAA) supplementation on nitrogen balance, urinary pH, and slurry pH in nursery pigs. Twelve barrows with an initial body weight of 15.2 kg (standard deviation = 0.7) were individually housed in metabolism crates. A quadruplicated 3 × 2 incomplete Latin square design with 3 experimental diets and 2 periods per square was employed. Experimental diets based on corn, soybean meal, whey powder, fish meal, and blood plasma were formulated to contain 19.4% CP, 17.5% CP, and 15.7% CP by reducing inclusion rates of soybean meal. All experimental diets were supplemented with EAA to meet all EAA requirements. Each period consisted of a 4-day adaptation period and a 24-hour collection period followed by a 4-day collection period. On day 5, feces and urine were collected for 24 h and the feces and urine were mixed in a ratio of fecal weight and urine weight at the end of collection to obtain slurry samples. Then, pH of urine and slurry samples was measured immediately. On days 6 and 10, chromic oxide was added at 0.5% in morning meals as a marker and the marker-to-marker procedure was used for the quantitative collection of feces. Urine collection was initiated at 1000 h on day 6 and terminated at 1000 h on day 10. Orthogonal polynomial contrasts were performed to test linear and quadratic effects of dietary CP concentrations on the response variables. Daily N intake was linearly decreased with decreasing dietary CP concentrations (P < 0.05). Daily fecal and urinary N excretions linearly decreased with decreasing dietary CP concentrations (P < 0.05), whereas N retention rate as % of intake was linearly increased with decreasing dietary CP concentrations (P < 0.05). The urine pH and slurry pH were linearly decreased with decreasing dietary CP concentrations (P < 0.05). In conclusion, lowering dietary CP concentrations decreased N excretion and pH of urine and slurry.

International Society of Sports Nutrition Position Stand: Effects of essential amino acid supplementation on exercise and performance.

Position Statement: The International Society of Sports Nutrition (ISSN) presents this position based on a critical examination of literature surrounding the effects of essential amino acid (EAA) supplementation on skeletal muscle maintenance and performance. This position stand is intended to provide a scientific foundation to athletes, dietitians, trainers, and other practitioners as to the benefits of supplemental EAA in both healthy and resistant (aging/clinical) populations. EAAs are crucial components of protein intake in humans, as the body cannot synthesize them. The daily recommended intake (DRI) for protein was established to prevent deficiencies due to inadequate EAA consumption. The following conclusions represent the official position of the Society: 1. Initial studies on EAAs' effects on skeletal muscle highlight their primary role in stimulating muscle protein synthesis (MPS) and turnover. Protein turnover is critical for replacing degraded or damaged muscle proteins, laying the metabolic foundation for enhanced functional performance. Consequently, research has shifted to examine the effects of EAA supplementation - with and without the benefits of exercise - on skeletal muscle maintenance and performance. 2. Supplementation with free-form EAAs leads to a quick rise in peripheral EAA concentrations, which in turn stimulates MPS. 3. The safe upper limit of EAA intake (amount), without inborn metabolic disease, can easily accommodate additional supplementation. 4. At rest, stimulation of MPS occurs at relatively small dosages (1.5-3.0 g) and seems to plateau at around 15-18 g. 5. The MPS stimulation by EAAs does not require non-essential amino acids. 6. Free-form EAA ingestion stimulates MPS more than an equivalent amount of intact protein. 7. Repeated EAA-induced MPS stimulation throughout the day does not diminish the anabolic effect of meal intake. 8. Although direct comparisons of various formulas have yet to be investigated, aging requires a greater proportion of leucine to overcome the reduced muscle sensitivity known as "anabolic resistance." 9. Without exercise, EAA supplementation can enhance functional outcomes in anabolic-resistant populations. 10. EAA requirements rise in the face of caloric deficits. During caloric deficit, it's essential to meet whole-body EAA requirements to preserve anabolic sensitivity in skeletal muscle.

Breastfeeding and Inborn Errors of Amino Acid and Protein Metabolism: A Spreadsheet to Calculate Optimal Intake of Human Milk and Disease-Specific Formulas.

Human milk (HM) offers important nutritional benefits. However, except for phenylketonuria (PKU), there are little data on optimal levels of consumption of HM and a special formula free of disease-related amino acids (SF-AA) in infants with inborn errors of metabolism of amino acids and proteins (IEM-AA-P). We designed a spreadsheet to calculate the amounts of SF-AA and HM required to cover amino acid, protein, and energy needs in patients with the nine main IEM-AA-P in infants aged under 6 months. Upon entering the infant's weight and the essential amino acid or intact protein requirements for the specific IEM, the spreadsheet calculates the corresponding required volume of HM based on the amino acid concentration in HM. Next, the theoretical daily fluid intake (typical range, 120-200 mL/kg/day) is entered, and the estimated daily fluid intake is calculated. The required daily volume of SF-AA is calculated as the difference between the total fluid intake value and the calculated volume of HM. The spreadsheet allows for the introduction of a range of requirements based on the patient's metabolic status, and includes the option to calculate the required volume of expressed HM, which may be necessary in certain conditions such as MMA/PA and UCD. In cases in which breastfeeding on demand is feasible, the spreadsheet determines the daily amount of SF-AA divided over 6-8 feeds, assuming that SF-AA is administered first, followed by HM as needed. Intake data calculated by the spreadsheet should be evaluated in conjunction with data from clinical and nutritional analyses, which provide a comprehensive understanding of the patient's nutritional status and help guide individualized dietary management for the specific IEM.

Perspective: Developing a Nutrient-Based Framework for Protein Quality

The future of precision nutrition requires treating amino acids as essential nutrients. Currently, recognition of essential amino acid requirements is embedded within a generalized measure of protein quality known as the PDCAAS (Protein Digestibility-Corrected Amino Acid Score). Calculating the PDCAAS includes the FAO/WHO/UNU amino acid score, which is based on the limiting amino acid in a food, that is, the single amino acid with the lowest concentration compared to the reference standard. That “limiting” amino acid score is then multiplied by a bioavailability factor to obtain the PDCAAS, which ranks proteins from 0.0 (poor quality) to 1.0 (high quality). However, the PDCAAS has multiple limitations: it only allows for direct protein quality comparison between 2 proteins, and it is not scalable, transparent, or additive. We therefore propose that shifting the protein quality evaluation paradigm from the current generalized perspective to a precision nutrition focus treating amino acids as unique, metabolically active nutrients will be valuable for multiple areas of science and public health. We report the development and validation of the Essential Amino Acid 9 (EAA-9) score, an innovative, nutrient-based protein quality scoring framework. EAA-9 scores can be used to ensure that dietary recommendations for each essential amino acid are met. The EAA-9 scoring framework also offers the advantages of being additive and, perhaps most importantly, allows for personalization of essential amino acid needs based on age or metabolic conditions. Comparisons of the EAA-9 score with PDCAAS demonstrated the validity of the EAA-9 framework, and practical applications demonstrated that the EAA-9 framework is a powerful tool for precision nutrition applications.

Pattern of Amino Acid Requirements in Humans: An Interspecies Comparison using Published Amino Acid Requirement Recommendations

We undertook an interspecies comparison of essential (indispensable) amino acid requirements, in relation to those for total protein, to examine whether the current, internationally proposed human amino acid requirement patterns are significantly different from those of other animals. Data were compiled in their original form and then expressed as mg amino acid/g total dietary protein (N × 6.25) required (amino acid requirement pattern). Patterns of requirements within the various species were organized according to four, arbitrary age-developmental groupings (very young, early growth, growth and mature), and these were compared with the requirements for (a) human infants, (b) 2–5 year old children, (c) 10–12 year old children and (c) adults, respectively. Statistical comparisons determined if significant differences existed between humans and other species, at apparently similar age-development stages, for both the total and for individual indispensable amino acids. The sum of the specific indispensable amino acid requirements for humans was significantly different than that for other species at infancy, growth and adulthood; the greatest differences, however, were for the amino acid requirement pattern in adulthood. The change between the very young and adult was the greatest for humans. Some of this difference might be due to experimental factors, including the biological status of a species within the arbitrary groupings described and the criteria used to determine “requirements.” Nevertheless, it is difficult to escape the conclusion that the current international human amino acid requirements, for adults in particular, appear to be anomalous when judged against data for other animal species.

Replacement of Dietary Fishmeal by Black Soldier Fly Larvae (Hermetia illucens) Meal in Practical Diets for Juvenile Tench (Tinca tinca)

The development of specific diets for the juvenile stage is a main target for culture intensification of tench (Tinca tinca). Aquafeeds still rely heavily on the use of fishmeal (FM) but concerns about economic and ecological sustainability make the use of alternative protein sources necessary. Insect meals are considered a promising substitute to replace FM. In a 90-day experiment, 6 diets with different replacement levels of FM by partially defatted black soldier fly larvae meal (BSFLM): 0%, 15%, 30%, 45%, 60% and 75%, were tested on juvenile tench. Survival rates were high (95.8–100%) without differences between treatments. Diet with 45% FM replacement allowed for best growth performance in terms of total length (TL = 66.4 mm) and weight (W = 4.19 g), without differences with 60% and 75% of replacement. A cubic relationship was evidenced between the level of FM replacement and growth. From the regression equations, the estimated optimal level of FM replacement was 47% (356 g BSFLM kg−1 diet). Externally visible deformities were always under 0.05%. The whole-body lipid content of the fish had a significantly negative linear regression with BSFLM (r2 = 0.80). The content of the essential amino acids (EAA) arginine, leucine, lysine, phenylalanine, methionine, and threonine in diets decreased with dietary BSFLM inclusion. However, it did not have a negative effect on growth performance, suggesting that EAA requirements were covered. The amount of essential amino acids in whole-body juveniles was similar independently of the diet provided. The results allow considering BSFLM as a sustainable protein source for juvenile tench feeding.

Protein Content and Amino Acid Profiles of Selected Edible Insect Species from the Democratic Republic of Congo Relevant for Transboundary Trade across Africa.

This study analyzed the protein content of ten edible insect species (using the Dumas method), then focused on the amino acid (AA) profiles of the six major commercially relevant species using HPLC (high-pressure (or performance) liquid chromatography). The protein contents varied significantly from 46.1% to 52.9% (dry matter); the Orthoptera representative yielding both the highest protein content and the highest values in three essential amino acids (EAAs). Regarding Lepidoptera species, the protein content of Saturniidae varied more than for Notodontidae. Imbrasia ertli gave the best example of a species that could be suggested for dietary supplementation of cereal-based diets, as the sample contained the highest values in five EAAs and for the EAA index. Furthermore, first-limiting AAs in the selected insects have also been pointed out (based on a species-specific AA score), supporting that the real benefit from eating insects is correlated to a varied diet. Additionally, preliminary insights into AA distribution patterns according to taxa provided three clusters based on protein quality and should be completed further to help tailor prescriptions of dietary diets. Since the AA composition of the selected insects was close to the FAO/WHO EAA requirement pattern for preschool children and met the requirements of 40% EAAs with high ratio EAAs/NEAAs, the current study endorses reports of edible insects as nutrient-rich and sustainable protein sources.

257 Effect of the Essential Amino Acid-Nitrogen to Total Nitrogen Ratio on Lysine Requirement for Nitrogen Retention in Growing Pigs

Abstract Low-protein (LP) diets may become limiting in nitrogen (N), affecting utilization of essential amino acids (EAA) for nitrogen retention (NR). The objective of the present study was to determine the effect of the EAA-N to total N ratio (EAA-N:TN) on lysine (Lys) requirement for NR. A total of 80 growing barrows (21.5±0.89 kg initial BW) were randomly assigned to 1 of 10 dietary treatments (n=8 pigs/treatment) in 8 blocks in a 2 × 5 factorial arrangement with factors of EAA-N:TN (low vs. high) and Lys content (0.82, 0.92, 1.02, 1.12, and 1.22% standardized ileal digestible [SID] Lys). Diets were formulated to meet EAA requirements with the low ratio diet (LR; 16.8% crude protein) having an ideal EAA-N:TN of 0.48 and the high ratio diet (HR; 15.5% crude protein) formulated to be limiting in NEAA with an EAA-N:TN of 0.55. Diets were fed at 2.8 × maintenance metabolizable energy requirements. After a 7-d dietary adaptation, a 4-d N-balance period was conducted where fresh fecal samples were collected daily and quantitative urine samples were collected over a 24-h period. Nitrogen-balance was determined as the difference between N intake minus fecal and urinary N output. Data were analyzed using a MIXED model with fixed effects of ratio, Lys, and their interactions, and block as a random effect. Lysine requirement based on two-phase linear or quadratic modeling was estimated using PROC NLIN. Nitrogen retention increased linearly with increasing Lys levels regardless of ratio (P< 0.01). Quadratic modelling estimated the Lys requirement to maximize NR at 17.83 g/d in pigs fed HR diets at 1.21% SID (R2 = 0.53; P< 0.05), but no breakpoint was achieved for pigs fed LR diets, which showed a linear response (R2 = 0.79; P< 0.05). These results suggest that NR is limited by NEAA or TN in HR diets.

Amino Acid Profiling and SDS-PAGE Analysis of Protein Isolates Obtained from Nonconventional Sources

Proteins play an imperative role in enhancing the nutritional status of the human body. The present study was designed to determine the molecular weight of protein isolates prepared from defatted oilseeds, i.e., sesame, flaxseed, and canola, using SDS-PAGE. The electropherogram revealed protein bands ranging from 15 to 65 kDa. Furthermore, proteins were subjected to amino acid profiling followed by calculation of amino acid score with reference to requirement for preschool children. The amino acid profiling results indicated that sesame protein isolates (SPI) exhibited the highest values for aromatic amino acids, histidine, isoleucine, and valine. However, the maximum values for sulfur-containing amino acids were depicted by flaxseed protein isolates (FPI). Moreover, the lysine content was highest in canola protein isolates (CPI). Results indicated better profile and quality of proteins, capable to meet the requirements of essential amino acids, especially for preschoolers. Moreover, the values for the protein digestibility corrected amino acid score (PDCAAS) and in vitro protein digestibility (IVPD) were also determined. Conclusively, protein isolates from defatted oilseeds exhibit better-quality proteins with a balanced amino acid profile. By potential utilization in numerous food products, these proteins can play a pivotal role in fulfilling the nutritional requirements of individuals, especially in developing economies.

The optimal dietary arginine level of laying hens fed with low-protein diets

BackgroundArginine (Arg) is an essential amino acid (EAA) in poultry, an important substrate for protein synthesis and a precursor of several molecules. Supplementation of EAAs with low protein (LP) diet increases the utilization efficiency of dietary crude protein (CP). However, if the EAA requirement is changed in hens fed a LP diet remains to be elucidated. The aim of the present study was to evaluate the optimal level of dietary Arg in the LP diet of hens. A total of 1350 Hy-Line Brown laying hens were randomly allocated to six dietary treatments: a basal diet (16% CP, positive control), or an isoenergetic LP diet (14% CP, 0.80% Arg) supplemented 0, 0.05%, 0.10%, 0.15%, and 0.20% L-Arg, corresponding to 0.80%, 0.85%, 0.90%, 0.95% and 1.00% dietary Arg, respectively.ResultsThe feed efficiency was decreased (P < 0.05) by 0.80% and 1.00% Arg-LP diets, compared to control. Within LP diets, dietary Arg level had significant quadratic effects (P < 0.05) on laying rate, egg mass, and feed efficiency. Compared to control, the plasma CAT activity or T-AOC content were decreased by 0.80% (P < 0.001). However, the hens offered 0.85% and 0.90% Arg-LP diets had higher CAT activity (P < 0.001) than 0.80% Arg-LP diet. In contrast, 1.00% Arg-LP group had the highest MDA and the lowest T-AOC content in plasma, liver, duodenal and jejunal mucosa (P < 0.05). Compared to control, the villus height was decreased by 0.80%, 0.95% and 1.00% Arg-LP diets, while the villus height to crypt depth (V/C) ratio was reduced by 0.95% and 1.00% Arg-LP diets in duodenum.ConclusionThe result demonstrates that LP diet (14% CP) deficient in Arg (0.80% Arg) result in augmented oxidative damage and impaired development of intestinal mucosa. According to the quadratic broken-line regression model, the optimal dietary arginine levels for Hy-Line Brown laying hens fed with low protein diet (14% CP) aged 33 to 40 weeks are 0.85%, 0.86%, and 0.86% to obtained the maximum laying rate, egg mass, and feed efficiency, respectively.

Comparison the Effect of Bromelain and Papain Enzymes on Fish Food which Prepared from Poultry Waste Powder on Common Carp (Cyprinus Carpio L.) Growth Performance

The study was conducted in the Fish Laboratory / College of Agriculture / University of Tikrit to study the effect of poultry waste powder supplemented with the Bromelain and Papain enzymes at rates of 2% and 3% on growth rates, 60 fish were randomly distributed with two replicates for each treatment, 6 fish for each replicate into 10 aquaria. The fish feed containing poultry droppings powder were prepared and chemical analyzes were conducted and they were used to feed common carp fish Cyprinus Carpio L. Treatment T3 recorded the highest weight gain of 91.49 g, while it decreased in treatment T2 to 69.85 g. The relative growth rate of treatment T3: 54.62% increased, and the specific growth of 0.30 g / day, and the efficiency of food conversion decreased in treatment T4: 28.30% compared with the other treatments. Significant differences were recorded at the level (P≤0.05) between the different experimental treatments, and most of the treatments covered the common carp requirements of essential amino acids.

Muscle amino acid profiles of eleven species of aquacultured animals and their potential value in feed formulation

The complete quantitative essential amino acid (EAA) requirements of aquacultured animals are largely unknown except for a handful of species. This is problematic because formulation of least-cost diets for target animals demands precise knowledge of EAA requirements. One way of approximating EAA requirements is to use correlations between whole-body and/or muscle EAA profiles using essential to total EAA ratios (A/E ratios). This method requires a reference, quantified EAA requirement, usually lysine (Lys). To systematically evaluate the A/E ratio method, muscle AA profiles were measured in 10 species of teleost and whiteleg shrimp. In fish, Lys represented the dominant muscle EAA measured, ranging between 7.06 and 9.58 g/100 g protein, whereas, in shrimp, arginine (Arg) was quantified as the principal EAA. For non-EAA, glutamate (Glu) and glutamine were consistently the NEAA recorded at highest levels whereas, in shrimp, Glu + Gln was highest followed by aspartate (Asp) plus asparagine (Asn). Except for Arg, which was twice that of fish (P < 0.05), whiteleg shrimp expressed similar muscle A/E profiles. Strength of relationship between muscle EAA levels and known requirements were all strongly and positively correlated for non-salmonid species. When using Lys as the reference EAA there were few semblances between measured and estimated EAA requirements.

118 Awardee Talk: An Empirical Model of Essential Amino Acid Requirements in the Pregnant Sow

Abstract Amino acid (AA) requirements are generally considered to be the minimum needed for maximum growth or protein synthesis; however, multiple studies have shown that AA intakes above these requirements improve various body functions such as immune response, gut health, and reproduction. The objective of the current modeling approach was to estimate AA intake in gestation that considered protein synthesis as well as sow reproductive performance and offspring development, potentially increasing piglet growth and survivability. A literature review was conducted to identify studies evaluating the effects of sow AA intake during gestation on protein synthesis, sow body weight, litter size, average piglet birth weight and suckling piglet growth rate. Data from 26 empirical studies from 1989 to 2021 were selected for model development and estimation of arginine, leucine, lysine, methionine, threonine, and valine requirements. To check model accuracy and performance, a validation analysis was conducted by contrasting the model predicted lysine requirements with data from 17 published studies not used in the development of the model. The estimated lysine requirement was approximately 40% greater than the minimum lysine intake required for maximum protein synthesis. Similarly, the ratios of arginine, leucine, methionine, and valine to lysine were on average 1.60, 2.47, 0.41, and 0.79, respectively, which are 6 to 300% greater than, and the ratio of threonine to lysine was similar to, current recommendations. The validation analysis showed that the estimated lysine requirement resulted in the greatest litter size and birth weight. In addition, when compared with lysine intakes that met current recommendations, lysine intake at the estimated requirement improved colostrum and milk quality, stillborn rate, proportion of low birth weight, suckling piglet growth rate, and sow blood urea, among other metabolic variables. In conclusion, at the estimated requirements sow reproductive performance as well as piglet survivability and growth rate are improved.

Effects of washing step and salt-addition levels on textural and quality properties in the chicken-surimi products

The massive wastewater from surimi manufacture and salt addition is controversial. In our previous study, a chicken-surimi (CS) product can be successfully developed from the spent-hen breast via 3 times of washing steps and 2.5% salt addition in the recipe. Due to the characteristics of broiler breast (higher protein contents in muscle), this study was to optimize the washing step for CS batter recovered from broiler breast and the salt-addition level in the CS-product recipe. The step of washing once with 0.1% salt solution showed no (P > 0.05) differences in the texture profile and color parameters (expect a* value) in CS batters compared to initial washing steps (a 3-step washing procedure). The CS batter obtained by this washing step had higher amino-acid contents than boiler breast and large Grade A egg and even fit adults’ daily essential amino-acid requirement. Besides, the lower (P < 0.05) water loss of cooked CS products during the storage (4°C) was shown beyond 2.0% salt addition in CS products. For efficient/ecofriendly extraction and sodium-content reduction, the washing once with a 0.1% salt solution and 2% salt addition in the recipe is recommended in the CS batter recovered from broiler breast and its products, respectively.

Doris Howes Calloway

At the beginning of her career after World War II, Doris Howes Calloway pushed forward into the rapidly expanding world of science and medicine and, for more than 50 years, focused her energies, abilities, and knowledge of foods, biochemistry, and physiology to advance the field of human nutrition as a science and to improve public health for all. She extended the importance of her research and thinking into contemporary social issues of poverty, disparity, diversity, and inequities of hunger and malnutrition. Dr Calloway was a product of her times, overcoming obstacles presented by the Great Depression, World War II, and male dominance in science. Throughout her career, she advocated for the training, hiring, and promotion of women and for racial/ethnic diversity among students and faculty. Her legacy is that of a humanitarian as well as of a stellar scientist, university administrator, leader, and mentor. Dr Calloway was a renowned human nutrition scientist revered by her colleagues and students. Her research interests were broad with a far-reaching impact. Her pioneering research helped to establish protein and energy requirements, and the interaction of nutrition and physical activity. Later, her research extended to food composition and food properties, altered needs during space flight, nutrient requirements of reproductive women, and essential amino acid, mineral, and folate requirements. She ventured outside the laboratory to investigate nutritional problems among Native American, migrant, and other underserved populations. Her visionary approach to research, community interventions, and mentoring led to science-based strategies to improve the nutritional status of vulnerable populations in Mexico, Egypt, and Kenya. The constant throughout Dr Calloway's research was the impact of nutrition on the health, performance, and well-being of the population. She was particularly concerned about the physiological consequences of food inadequacy among impoverished populations. Dr Calloway referred to this work as a “foray into the real-world nutrition problems.” Her work addressed contemporary social issues related to food access and quality, including health disparities. At a time when many scientists were narrowly focused, Dr Calloway maintained a broad portfolio of inclusiveness in her research and its application. Twenty years after her death, Dr Calloway's work continues to influence global nutrition as a result of her pioneering research theories and techniques. The scope of her contributions to human nutrition reaches far beyond her own research, to the outstanding contributions made through her 33 graduate students and numerous postdoctoral fellows and visiting scientists. She passed on to this network of students not only her excellent research methods and their applications but also her personal values of rigor, objectivity, integrity, and human equality. Dr Calloway's students continue her legacy, and many are now recognized as major contributors in the research and application of nutrition theory and practice. This article is the first in a series of publications that focus on the areas of research that Dr Calloway conducted, the impact of her work at the time the findings were published, and the continued contributions to contemporary scientific discourse around human nutrition, dietetics, and public health.