Amino Acid Feeding Research Articles

Effect of Lysine Amino Acid in Artificial Feed Substituted with Moringa (Moringa oleifera L.) Leaves on Feed Efficiency of Bileh Fish Seeds (Rasbora sp.)

This study aims to test the effectiveness of amino acid lysine in artificial feed in increasing feed efficiency of bileh fish fry (Rasbora sp.). The experimental design used was a non-factorial completely randomized design (CRD) with five treatments and three replications. The treatments included: feed without lysine (P0), feed with lysine 1.2%/kg (P1), 1.4%/kg (P2), 1.6%/kg (P3), and 1.8%/kg (P4). The fish fry used amounted to 10 fish per container with a size of 2 cm and a weight of 0.10 grams, reared for 40 days. The results of data analysis using ANOVA showed that the provision of amino acid lysine had a significant effect on specific growth rate, but no significant effect on survival, feed conversion ratio and feed efficiency.

Myofibrillar Protein Profile of The Breast Muscle in Turkeys as a Response to The Variable Ratio of Limiting Amino Acids in Feed

The effects of the different dietary levels of Arginine (Arg) in low- and high-methionine (Met) diets on the meat quality and myofibrillar protein profile of breast muscles from turkeys were determined. The experiment had a completely randomized 3 × 2 factorial design with three levels of Arg (90%, 100%, and 110%) relative to the dietary Met levels (30% or 45%). At 42 days of age, eight turkeys from each treatment were sacrificed; the meat pH value was measured at 48 h post-slaughter, and meat color was measured according to the CIE L*a*b* system. The SDS-PAGE method was performed to investigate the myofibrillar protein profile of the breast muscle. The analysis of variance showed a significant effect of the Arg or Met dietary levels on the color parameter b* and the profile of myofibrillar proteins in muscles. The results of the cluster analysis of the myofibrillar protein profile showed that, with a high level of Arg (i.e., 110%), the level of Met 35% or 45% was less important. It can be concluded that the increase in the share of Arg and Met in the diet of turkeys increases the content of some myofibrillar proteins (actinin, desmin, actin) and reduces degradation during the post-slaughter proteolysis of proteins that are considered tenderization indicators.

Peptide aptamer-based colorimetric sensor for the detection of L-tryptophan in porcine serum

L-Tryptophan (L-Trp), one of the essential amino acids, is crucial for human physiological homeostasis and a limiting amino acid in animal feed. In addition, L-Trp is a precursor of some important biomolecules in the body, such as pentraxin and melatonin. Disorders of L-Trp metabolism in the body may cause Alzheimer's or Parkinson's disease. Therefore, monitoring L-Trp levels in the body fluids quickly and accurately is essential. A colorimetric biosensor was developed for the rapid detection of L-Trp in solutions by coupling a novel, screened, and validated peptide aptamer with Au nanoparticles via the Au-S bond. The biosensor showed a wide linear detection range of 1 µM − 1000 µM, and in addition, it was simple to construct, and the reaction time was as short as 10 s. In the analysis of L-Trp in actual porcine serum samples, the relative standard deviations were 4.52 % to 3.01 % compared with those of the high-performance liquid chromatography method, and the spiked recoveries were 99.2 % to 100.2 %. This new type of recognition probe is likely to gain attention in the field of bioanalysis owing to its biocompatibility, ease of modification, and easy linkage to nanomaterials.

Nonessential amino acids in tropical ruminant feed: Investigating grass and legume forages of Indonesia.

This study aimed to examine the concentration of nonessential amino acids (NEAAs) in ruminant feed in tropical areas, with a focus on forage grasses and legumes in Indonesia. A total of 11 grasses (Chrysopogon zizanioides, Brachiaria brizantha, Brachiaria humidicola, Paspalum dilatatum, Paspalum atatum, Chloris gayana, Pennisetum polystachion, Panicum maximum, Cenchrus biflorus, Andropogon canaliculatus, and Digotaria decumbens) and six legumes (Arachis hypogaea, Pueararia Javanica, Centrosema pubescens, Clitoria ternatea, and Arachis pintoi) were analyzed for NEAA content using high-performance liquid chromatography (HPLC). Based on the results of this research, it was found that almost all NEAA content in forage was less than 3% (Serine (Ser), Alanine (Ala), Glycine (Gly), Tyrosine (Tyr), Proline (Pro), Cysteine (Cys), and Asparagine (Asn), except for glutamic (Glu) acid and arginine (Arg) in some legumes. The Glu content in grass ranges from 0.76% to 2.61%, and the Arg content ranges from 0.92% to 2.09%. These two NEAAs were most abundant in grasses and legumes, with concentrations of 5.10% to 6.27% and 3.10% to 5.53%, respectively. Our study concluded that Glu and Arg were the most abundant NEAAs in tropical forages in Indonesia, with legumes having a higher concentration of NEAAs compared to grasses. Among the legumes, A. hypogaea had the highest NEAA content (23.40%), while among the forages, C. zizanioides had the highest NEAA content (12.37%). However, it was observed that neither legumes nor grasses could fulfill the metabolizable TNEAAs requirements for gaining cattle (250 kg of empty body weight gain), unlike commercial concentrates, which were found to meet the requirements, especially for Arg, Glu, and thyronine. The provision of concentrate is necessary to supplement forage to meet the NEAA needs for cattle.

Effects of Immunocastration and Amino Acid Supplementation on Yearling Fallow Deer (Dama dama) Testes Development.

Forty-four fallow deer bucks (10 months old; 22.9 ± 2.4 kg) were utilized to investigate the effects of immunocastration and amino acid supplementation on testes development. Immunocastrated bucks were administered Improvac® at weeks 1, 8, and 20 of this study (control group: intact males). Starting at week 8, half of each sex received rumen-protected lysine and methionine (3:1) supplementation. At slaughter (week 37/39), body size, internal fat deposits, antler size parameters, testes weight, testes surface color, cauda epididymal sperm viability and morphology, and seminiferous tubule circumference and epithelium thickness were determined. Animals with larger body sizes, greater forequarter development, and antler growth also had greater testes development. Whilst the result of immunocastration on testes size is unexpected, testes tissue showed impaired development (atrophied seminiferous tubules), decreased sperm viability, and normal morphology. Testes tissue from immunocastrated deer was less red, possibly indicating reduced blood supply. Conversely, amino acid supplementation increased testes' redness and sperm viability, and intact males fed amino acids showed the greatest seminiferous tubule development. Thus, immunocastration may be a welfare-friendly alternative for venison production. Whilst the results support findings from the literature that testes size is not a reliable indicator of immunocastration success, this warrants further investigation in deer over different physiological development stages.

Application of near infrared spectroscopy for identification and quantitative determination of amino acids in their crystalline and salt forms in the preparation of animal feed

Methods. For the first time, a comprehensive calibration model has been developed and presented for the rapid determination of basic near-infrared spectroscopy (IR) methods in feed amino acids, with application in the production of animal feed. The research principle is based on the Fourier equation for spectroscopy. In this work, Fourier methods in the Italian region (FTIR, FT-NIRS) were applied. The data obtained from the calibration models were confirmed using high-performance liquid chromatography. FT-NIR predictions agreed well with the chromatography data and had predictive deviation (RPD) values >1.3 in all cases.Results. The results indicate that FT-NIR spectroscopy can be used as a simple and rapid tool for monitoring amino acids. In the course of the work, experimental confirmation of previously known facts was obtained — the possibility of visual separation of the spectra of not only counterfeit amino acids, but also the possibility of separation by L- and DL-optical isomers. The work shows that the discrepancies between the values obtained by the classical “wet chemistry” method and the values obtained from the constructed calibration models do not exceed the reproducibility limits of arbitration methods. A predictive model was used based on information flow elements using the OPUS/QUANT2 software package for multivariate calibration and construction of calibration models for amino acids. This chemometric analysis proved the fundamental possibility of determining amino acids in the product. It has been shown that the use of information channels opens up opportunities for the use of many chemometrics algorithms, including data preprocessing and the construction of predictive models.

Development and Validation of a Method for Hydrolysis and Analysis of Amino Acids in Ruminant Feeds, Tissue, and Milk Using Isotope Dilution Z-HILIC Coupled with Electrospray Ionization Triple Quadrupole LC-MS/MS.

Current analytical methods for amino acid (AA) analysis in ruminant nutrition are time-consuming and expensive. This study aimed to develop a method for AA analysis that is faster, more efficient, rugged, and accessible. Four representative matrixes were selected for method development and validation: milk, tissue, feed, and soy flour standard reference material from National Institute of Standards and Technology. Acid and alkaline hydrolysis were used to analyze 18 AA. Separation of AA was performed using a Z-HILIC column in an 18-min run coupled to a triple quadrupole LC/MS system in positive and negative electrospray ionization for identification and quantitation. The method was evaluated for recovery, precision, calibration curve linearity, and limits of detection (LODs) and limits of quantitation (LOQs) and applied to other feed samples. Good quantitation results were achieved for all AA, with coefficients of determination (R2) over 0.995; LODs at 0.2-28.2 and LOQs at 0.7-94.1 ng/mL; intraday and interday precision <14.9% relative standard deviation; blank recovery between 75.6 and 116.2%; and sample recovery between 75.6 and 118.0%. Overall, AA concentrations were similar to literature values, and there was a tendency for higher N recovery as AA. In conclusion, an efficient and robust method was validated to routinely analyze AA for appropriate characterization in diet formulation for dairy cattle.

Amino acids profile of six freshwater Algae in the northern region of Bangladesh: A solution for the protein supplement of poultry feed

Algae is an important natural source of protein, specifically amino acid source, which are the building blocks of enzymes, hormones, nucleic acids, etc. Herein, the amino acid composition was investigated in six commonly growing fresh-water algae. The number of amino acids in Oscillatoria brevis, Spirulina platensis, Pithophora kewensis, Euglena viridis, Hydrodictyon reticulatum, and Aphanocapsa holsatica were detected 15, 12, 17, 15, 14, and 15, respectively. Among studied algal species, the amino acids: proline (29239.3 ± 276.4 μg/g), histidine (10056.8 ± 85.4 μg/g), aspartic (3030.6 ± 48.6 μg/g), threonine (1492.3 ± 31.8 μg/g) were detected in the highest amount in O. brevis, S. platensis, P. kewensis, A. holsatica, respectively. It is reported that the range of the ratio between 50/50 to 60/40 of essential amino acid/(nonessential amino acid + conditional essential amino acid) promotes maximum growth performance and best energy utilization. The obtained results of this study suggested that a combination of A. holsatica, H. reticulatum, and O. brevis can provide a good ratio (48/52) of amino acids and the noble source of essential amino acids for feed or food supplements, especially for poultry's stamina and, consequently, welfare.

Application of Corynebacterium glutamicum in L- threonine biosynthesis

L-threonine is an essential amino acid for human and animal nutrition. L-threonine is the second limiting amino acid in pig feed and the third limiting amino acid in poultry feed, primarily used as a feed additive. Currently, industrial production of L-threonine is achieved through fermentation using Escherichia coli. Corynebacterium glutamicum, a bacterium commonly used as an industrial production chassis for amino acids such as glutamic acid and L-lysine, possesses advantages such as biosafety and strong environmental adaptability. It is considered a potential strain for the efficient production of L-threonine. However, current production of L-threonine by C. glutamicum often leads to the accumulation of significant amounts of other amino acid by-products, limiting the level of L-threonine production. Previous studies that aimed to block or weaken the pathways for by-product synthesis resulted in strains with nutritional deficiencies or only partial reduction in by-product accumulation.

Inclusion of vermiculture biomass grown on a substrate of accelerated fermentation into combined feeds for broiler chickens

As the population increases, the problem of meat production will grow. An alternative method of solving this problem is growing broiler chickens; however, with this technology, the question of protein content and available amino acids in poultry feed remains open. Vermiculture biomass can be an inexhaustible source of protein for broiler chickens feeding. Under the vivarium of the Bila Tserkva National Agrarian University, worms were grown on a substrate containing poultry droppings with litter fermented by an accelerated method with the participation of a destructor. Therefore, the work aims to establish the effect of such vermiculture biomass on productivity and protein metabolism in the body of broiler chickens. For this purpose, the broiler chickens of the research groups were fed with compound feed with a content of 1.5, 3.0, and 4.5 % of vermiculture biomass. Poultry compound feed from the control group did not contain worm biomass. At the end of the experiment, the bird's body weight was recorded, the absolute and average daily gains were determined, and the indicators of protein accounting in the liver of broiler chickens were determined. It has been established that the body weight of broiler chickens varies depending on the content of vermiculture biomass in compound feed. Using a low dose of worms in the feed did not make it possible to obtain a statistically significant increase in the body weight of broiler chickens. By adding 3.0 and 4.5 % vermiculture biomass to the compound feed, the body weight of broilers increases by 3.5 and 3.7 % compared to the index of birds that were not fed worms. It was found that the absolute and average daily growth of broiler chickens that consumed compound feed containing 3.0 and 4.5 % vermiculture biomass increased by a statistically significant amount. It has been proven that using vermiculture biomass affects the protein metabolism indicators in broiler chickens' livers. In the liver of broiler chickens, which were fed with compound feed with a content of 3.0 and 4.5 % of vermiculture biomass, a tendency to an increase in the total protein content and a statistically significant increase in the activity of aspartate aminotransferase and alanine aminotransferase was established. In the liver of broilers, which were fed with compound feed with a content of 3.0 and 4.5 % of worm biomass, a tendency to increase the content of total and protein total groups was revealed.

Glutathione Peroxidase and Phospholipid Hydroperoxide Glutathione Peroxidase Are Differentially Regulated in Rats by Dietary Selenium

Phospholipid hydroperoxide glutathione peroxidase (PHGPX) and classical glutathione peroxidase (GPX1) are encoded by separate genes with only about 40% amino acid and nucleic acid sequence identity. To determine the response of tissue PHGPX expression to dietary Se level and to compare these responses with those for GPX1, weanling male rats were fed amino acid diets containing from 2 (-Se) to 130 (+Se) µg Se/kg diet or a torula diet containing 5 and 190 µg Se/kg diet as Na2SeO3 for 28 d. Tissues were analyzed for PHGPX and GPX1 activity and mRNA. There was no effect of Se on growth. In -Se rats, GPX1 activity was reduced to 1% in liver and 4–9% in heart, kidney and lung compared with +Se rats; PHGPX activity was reduced only to 25–50% in these four tissues. The Se response curves indicated that the dietary Se requirement to reach plateau liver PHGPX activity was half that required for plateau GPX activity. In -Se rats, liver and heart GPX1 mRNA levels were reduced to 6 and 12%, respectively, whereas PHGPX mRNA was not significantly affected by Se deficiency. Notably, 65 µg Se/kg diet resulted in plateau liver GPX1 mRNA levels but not plateau GPX activity. Testis had the lowest GPX activity and GPX1 mRNA of all tissues examined, but had 15-fold higher PHGPX activity and 45-fold higher PHGPX mRNA levels when compared with liver. There was no significant effect of dietary Se on testis GPX1 and PHGPX mRNA levels. This study demonstrates that these two selenoperoxidases are differentially regulated by dietary Se. Differences in Se regulation of mRNA levels in liver and heart were even more pronounced than for enzyme activity. The lack of any significant effect of reduced dietary Se on PHGPX mRNA levels suggests that there are detailed underlying molecular mechanisms whereby Se status regulates GPX1 mRNA levels but not PHGPX mRNA levels.

SLAUGHTER PARAMETERS OF BROILER CHICKENS AT DIFFERENT LEVELS AND RATIOS OF LYSINE AND THREONINE IN THE COMPOUND FEED

The article highlights the results of the study of the influence of different levels and ratios between lysine and threonine in compound feed of broiler chickens on slaughter indicators. The experiment was conducted by the group method on 600 heads of broiler chickens of the "Cobb-500" cross, which were divided into 6 groups of 100 heads each. In the combined feed of chickens of the first three groups against the background of the basic level of lysine, the level of threonine was increased. In the feed of the birds of the other 3 groups, the level of threonine was increased against the background of the increased level of lysine. It was established that the highest indicators of meat productivity in broiler chickens were established for the content of lysine and threonine in compound feed, respectively, in the first growing period (age 1–10 days) – 1.24 and 0.83%; in the second growing period (age 11–22 days) – 1.14 and 0.78% and in the third growing period (age 23–42 days) – 1.09 and 0.70%. When using compound feed with an effective content of lysine and threonine, pre-slaughter live weight increases by 0.65% (р&lt;0.05); weight of semi-carcasses - by 2.12% (р&lt;0.05); the mass of the cartridge carcass - by 3.85% (р&lt;0.05); pectoral muscle mass - by 12.27% (р&lt;0.05); muscle mass of the pelvic limbs - by 12.77% (р&lt;0.05); yield of semi-carcasses - by 1.25% (р&lt;0.05); cartridge carcass yield - by 2.50% (р&lt;0.05); output of pectoral muscles – by 2.34% (p&lt;0.05) and output of pelvic limb muscles – by 1.93% (p&lt;0.05). No antagonism between lysine and threonine has been established. Neither an increase in the content of lysine nor threonine caused a decrease in productivity or other negative consequences. The influence of the lysine-threonine ratio on the meat productivity of chickens has not been established. Productivity increased regardless of the ratio, with an increase in the content of both amino acids in the compound feed. However, the highest meat productivity was noted for the ratio of lysine to threonine in compound feed, in the first period of growing - 0.67: 1; in the second - 0.68: 1 and in the third - 0.70: 1.

Dietary sugars and amino acids increase longevity and enhance reproductive parameters of Bracon cephi and B. lissogaster, two parasitoids that specialise on wheat stem sawfly

AbstractThe wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae), is a major pest of wheat grown on the Northern Great Plains and Canadian Prairies of North America, causing economic losses of as much as $350 million annually. Two species that parasitize wheat stem sawfly larvae in wheat stems are Bracon cephi (Gahan) and B. lissogaster Muesebeck (Hymenoptera: Braconidae). Carbohydrate‐rich diets increase adult parasitoid longevity and reproductive parameters, enhancing their success as natural enemies. In previous studies, these species had increased longevity, egg load, and volume when fed sucrose solutions, encouraging further research on their nutritional needs. Therefore, we conducted experiments with artificial diets using adult females fed sucrose, glucose, and fructose solutions. Females were also fed these sugars in combination with a mixture of amino acids. We assessed individuals daily for longevity. Both species benefited from diets containing carbohydrates, with an increase in longevity from an average of 9 to 51 days for B. cephi, and from 6 to 34 days for B. lissogaster. Additional experiments assessed egg load and volume after 2, 5, and 10 days of cumulative feeding in B. cephi. These females produced 1.4‐fold more eggs when fed amino acids, 2.5‐fold more with sugar, and 2.7‐fold more when fed sugar with amino acids. They had a 1.3‐fold increase in egg volume when fed amino acids, 1.9‐fold with sugar, and 2.1‐fold when fed sugar with amino acids. Our study reveals the nutritional requirements of these braconid parasitoids and the benefits of nutritional sources when implementing conservation biological control strategies.

Color-Switchable Nanosilicon Fluorescent Probes.

Fluorescent probes are vital to cell imaging by allowing specific parts of cells to be visualized and quantified. Color-switchable probes (CSPs), with tunable emission wavelength upon contact with specific targets, are particularly powerful because they not only eliminate the need to wash away all unbound probe but also allow for internal controls of probe concentrations, thereby facilitating quantification. Several such CSPs exist and have proven very useful, but not for all key cellular targets. Here we report a pioneering CSP for in situ cell imaging using aldehyde-functionalized silicon nanocrystals (SiNCs) that switch their intrinsic photoluminescence from red to blue quickly when interacting with amino acids in live cells. Though conventional probes often work better in cell-free extracts than in live cells, the SiNCs display the opposite behavior and function well and fast in universal cell lines at 37 °C while requiring much higher temperature in extracts. Furthermore, the SiNCs only disperse in cytoplasm not nucleus, and their fluorescence intensity correlated linearly with the concentration of fed amino acids. We believe these nanosilicon probes will be promising tools to visualize distribution of amino acids and potentially quantify amino acid related processes in live cells.

Determination of amino acids in food and feed by microwave hydrolysis and UHPLC-MS/MS

The determination of amino acids in food and feed by chromatography has a long history and is described in several official methods, including standards from ISO, AOAC, and the European Commission (EC) regulation 152/2009. The procedure usually consists of labor- and time-consuming preparation techniques and ion-exchange chromatography with challenging chromatographic conditions. Consequently, several approaches have been published to overcome these drawbacks but the knowledge about their suitability for complex matrices such as food and feed is limited.In this paper, we describe the development of two new methods to determine amino acids in food and feed. These methods involve microwave hydrolysis and reversed-phase UHPLC-MS/MS with pre-column derivatization using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC). Both methods provide streamlined sample preparations and a dramatic reduction in analysis time while offering a high degree of specificity and selectivity. Selectivity also enabled the simultaneous determination of the more uncommon substances hydroxyproline, hydroxylysine, taurine, ornithine, and γ-amino butyric acid (GABA) along with amino acids typically present in food and feed. The results were all satisfactory with regards to sensitivity, accuracy, precision, and comparability with laboratories that use other methods, for example from ISO, AOAC, or regulation (EC) 152/2009. We therefore concluded that both methods provide a reliable and modern approach to overcome many of the drawbacks that occur with the conventional standard methods.

Improved offspring performance of broiler breeder hens fed amino acid complexed trace minerals

The present study aimed to evaluate the effects of partial substitution of inorganic trace minerals ( ITM ) by amino acid complexed minerals ( AACM ) on broiler breeder hens’ performance and offspring. A total of 640 Cobb 500 broiler breeder hens, 22 wk of age, were allocated to four dietary treatments: T1- (Control) contained ITM forms of Zn, Mn, Cu, Fe and Se at 100, 100, 10, 50 and 0.30 ppm, respectively; T2- (Partial replacement) of Control by AACM Zn, Mn, Cu, and Se at 60, 60, 3, and 0.15 ppm of ITM, and 40, 40, 7, and 0.15 ppm of AACM, respectively.; T3- (Partial replacement) of Control, same as T2 but with Fe at 10 and 40 ppm of ITM and AACM, respectively; T4- (On Top) supplementation of Zn, Mn, Cu, Se and Fe (T1+T3). Laying production was evaluated from 26 to 66 wk, whereas egg quality was evaluated at 35, 45, 55, and 65 wk of age. At each period, eggs were incubated and evaluated for hatchability parameters and chick quality. At 66 wk of age, eggs were incubated to obtain 800-day-old male chicks for the progeny performance trial. Total and settable egg production and incubation parameters were not affected by supplementation treatments (P > 0.05). Eggshell breaking strength significantly increased (P < 0.05) in the On Top supplementation group compared to the Control. The offspring from hens fed partially Zn, Mn, Cu, Se and Fe AACM had higher body weight gain ( BWG ) in the first week (P < 0.05) and maintained a smaller feed conversion ratio ( FCR ) from 1 to 35 d compared to the offspring of Control ITM group (P < 0.05). Maternal AACM supplementation increased offspring BWG and FCR from 1 to 7 d and 1 to 35 d, respectively.

Lysine regulates TOR and NPY through taste receptor T1R1 in Chinese perch (Siniperca chuatsi)

Chinese perch (Siniperca chuatsi), a typical carnivorous fish, has a high dietary protein requirement. The poor utilization of plant protein in carnivorous fish is well known, while the crucial mechanism has not been characterized. Lysine, generally the first limiting amino acid in plant-derived protein dietary feed, might play essential roles in regulating protein synthesis and feed intake. G protein-coupled taste receptor T1R1/T1R3 heterodimer as a direct sensor of extracellular amino acids (AA) availability via Ca2+ stimulation. In the present study, we identified the umami taste receptor genes and found that T1R1/T1R3 heterodimer could strongly respond to L-Lys in Chinese perch, and L-Lys could regulate the target of rapamycin (TOR) and Neuropeptide Y (NPY) through the taste receptor T1R1/T1R3 signaling pathway. The results suggested that lysine and its taste sensing system might be the essential targets when making efforts to replace fish meal with plant protein.

Effect of L-arginine and L-Lysine HCl ratio on growth performance and ileum morphology of native chickens aged 2-14 weeks.

Background and Aim:Micronutrients such as essential amino acids in chicken feed must be balanced to promote optimal development. The balance of the amino acids arginine and lysine in chicken feed is particularly important. This study aimed to examine the effect of the ratio of L-arginine to L-Lysine HCl on growth performance and ileum morphology of native chickens aged 2-14 weeks-old.Materials and Methods:One hundred and eighty 2-week-old native chickens which initial weight 78.10±4.97 g were classified into six treatments and five repetitions using a completely randomized design.Treatments were based on the ratio of arginine to lysine in the feed:T1 (0.50% L-arginine: 0.85% L-lysine HCl); T2 (0.75% L-arginine: 0.85% L-lysine HCl); T3 (1.00% L-arginine: 0.85% L-lysine HCl); T4 (0.50% L-arginine: 1.00% L-lysine HCl); T5 (0.75% L-arginine: 1.00% L-lysine HCl); and T6 (1.00% L-arginine: 1.00% L-lysine HCl).Results:Groups T3 and T6 had the highest feed consumption (42.06±0.29 and 42.78±0.72 g/bird/day, respectively), while Group T6 had the highest body weight and body weight gain rate (1505.60±103.20 kg/bird and 16.99±1.24 g/bird/day, respectively). Groups T3 and T6 also had the highest carcass weight (916.16±46.99 and 947.18±62.32 g/bird, respectively). The best feed conversion was seen for Groups T3, T5, and T6 (2.55±0.14, 2.50±0.20, and 2.53±0.19, respectively). For ileum morphometry, the highest villus height occurred in Groups T2, T3, T5, and T6 (962.80±23.31, 982.80±10.03, 972.80±18.99, and 989.80±10.69 μm, respectively); and Group T6 had the highest crypt depth and villus width (340.80±11.52 and 302.00±4.00 μm, respectively). Statistical analysis indicated significant differences among the treatment groups for all variables examined (p<0.05).Conclusion:The highest ratio of arginine-lysine was associated with the largest increase in native chicken feed consumption, body weight gain, feed conversion, and carcass weight, as well as villus height and width, and crypt depth in the ileum. Overall, an arginine-lysine ratio of 0.8-1.20 promoted optimal growth of native chickens aged 2-14 weeks. In the future, it is important to increase the arginine-lysine ratio with low feed protein levels in native chickens.

Combined analysis of silk synthesis and hemolymph amino acid metabolism reveal key roles for glycine in increasing silkworm silk yields

Rearing silkworms (Bombyx mori) using formula feed has revolutionized traditional mulberry feed strategies. However, low silk production efficiencies persist and have caused bottlenecks, hindering the industrial application of formula feed sericulture. Here, we investigated the effects of formula feed amino acid composition on silk yields. We showed that imbalanced amino acids reduced DNA proliferation, decreased Fib-H, Fib-L, and P25 gene expression, and caused mild autophagy in the posterior silk gland, reducing cocoon shell weight and ratio. When compared with mulberry leaves, Gly, Ala, Ser, and Tyr percentages of total amino acids in formula feed were decreased by 5.26%, while Glu and Arg percentages increased by 9.56%. These changes increased uric acid and several amino acids levels in the hemolymph of silkworms on formula feed. Further analyses showed that Gly and Thr (important synthetic Gly sources) increased silk yields, with Gly increasing amino acid conversion efficiencies to silk protein, and reducing urea levels in hemolymph. Also, Gly promoted endomitotic DNA synthesis in silk gland cells via phosphoinositide 3-kinase (PI3K)/Akt/target of rapamycin (TOR) signaling. In this study, we highlighted the important role of Gly in regulating silk yields in silkworms.

Effects of L-valine in layer diets containing 0.72% isoleucine.

In a previous study with LSL-LITE layers (-23 to 30-week-old), isoleucine at 0.72% and 0.84% produced values for FCR at 1.45 and 1.44, respectively and shared significance with 0.78% isoleucine (1.49). Considering that FCR is an important standard in the poultry industry due to the cost for adding feed ingredients such as synthetic amino acids and the low FCR of 1.45, 0.72% isoleucine was chosen for further study with LSL-LITE layers (n = 490 at 33- to 40-week-old) to determine effects on production and egg quality. The study included 7 diets (2730 Kcal kg metabolizable energy and constant isoleucine at 0.72%) containing varying quantities of valine [0.72 (Control), 0.75, 0.78, 0.81, 0.84, 0.87 or 0.90%] x 7 replicates x 10 hens/replicate. Significance at P ≤ 0.05 and P < 0.10 was determined. Level and week were significant for feed intake, egg production, and FCR; the interaction of level x week (L*W) was significant for feed intake and FCR. An isoleucine:valine of 1.233 corresponding to 0.72% isoleucine and 0.87% valine produced the lowest FCR of 1.30 (a 2.26% decrease compared to the Control at 1.33 ± 0.04). All measurements for external egg quality, except shape index and eggshell thickness, were significant for level. Week was significant for all parameters except shell thickness; L*W was significant for external quality measurements except shape index and shell thickness. Level, week, and L*W were significant for internal egg quality measurements. Serum protein and H1 titer were significant for level. Various production, egg quality, and biochemical measurements were significantly different from the control (0.72% isoleucine and 0.72% valine) at 0.81 to 0.87% valine. Findings of this study will aid researchers and commercial producers in narrowing the range of isoleucine, valine, and leucine needed for effects on particular parameters. Knowledge gained from this and others studies will eventually lead to an understanding of synergistic and antagonistic effects of branched chain amino acids in feed for various genetic types of layers throughout their productive lifetime.