scholarly journals Do Growing Rabbits with a High Growth Rate Require Diets with High Levels of Essential Amino Acids? A Choice-Feeding Trial

Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 824
Author(s):  
Pablo Jesús Marín-García ◽  
Mari Carmen López-Luján ◽  
Luís Ródenas ◽  
Eugenio Martínez-Paredes ◽  
María Cambra-López ◽  
...  
Keyword(s):  
Amino Acids ◽  
Growth Rate ◽  
Amino Acid ◽  
Growth Rates ◽  
Nutrient Retention ◽  
High Growth ◽  
Feeding Trial ◽  
Nutritional Recommendations ◽  
Sulphur Amino Acids ◽  
Choice Feeding

As a consequence of the genetic selection process in growing rabbits, there are currently fast-growing animals exhibiting an average daily gain that may exceed 45 g/d. The protein requirements of these animals, namely amino acid requirements, may differ from animals with low growth rates. The objective of this work was to evaluate growth performance, the coefficient of total tract apparent digestibility (CTTAD), the apparent ileal digestibility (AID) of amino acids and nutrient retention of fast-growing rabbits when they had access to a diet with high levels of amino acids and/or a diet formulated with current nutritional recommendations in a choice-feeding trial. To this end, two diets were formulated: the M diet following current nutritional recommendations for growing rabbits (including 8.1, 5.8 and 6.9 g/kg dry matter (DM) of total lysine, sulphur amino acids and threonine, respectively) and the H diet with higher levels of total lysine, sulphur amino acids and threonine (9.4, 6.6 and 7.8 g/kg DM, respectively). A total of 220 weaned rabbits, from a paternal line selected for the growth rate, had free access to the M diet, the H diet or both (MH) diets from 28 to 63 days of age. The CTTAD of DM, crude protein and gross energy from 49 to 53 days of age as well as the AID of amino acids of the diets at 63 days of age were determined. Protein, amino acids and energy retained in the empty body from 28 to 63 days of age were also registered. No significant differences in growth performance, CTTAD, AID and nutrient retention between dietary treatments were observed. However, animals fed the H diet showed a higher AID of cysteine (p < 0.05) and higher threonine retention (p < 0.05) compared to the M diet. As regards the choice-feeding trial, MH animals showed a higher feed intake of the M diet compared to the H diet (+8.61%; p < 0.001), and furthermore, more than 50% of the animals preferred the M diet throughout the experimental period (p < 0.05). Our results suggest that animals with high growth rates do not show significantly higher productive traits when fed the H diet compared to the M diet. As regards choice feeding, MH animals were capable of choosing their preferred diet, showing high intra-individual repeatability in preference for the M diet. It would be interesting to continue studying this behaviour of choice based on amino acid levels.

Very High Growth Rate of 4H-SiC Using MTS as Chloride-Based Precursor

2008 ◽  
Vol 600-603 ◽  
pp. 115-118 ◽  
Author(s):  
Henrik Pedersen ◽  
Stefano Leone ◽  
Anne Henry ◽  
Franziska Christine Beyer ◽  
Vanya Darakchieva ◽  
...  
Keyword(s):  
Growth Rate ◽  
Linear Dependence ◽  
Growth Rates ◽  
Molar Fraction ◽  
High Growth ◽  
High Growth Rate ◽  
Epitaxial Layers ◽  
Single Precursor ◽  
Very High

The chlorinated precursor methyltrichlorosilane (MTS), CH3SiCl3, has been used to grow epitaxial layers of 4H-SiC in a hot wall CVD reactor, with growth rates as high as 170 µm/h at 1600°C. Since MTS contains both silicon and carbon, with the C/Si ratio 1, MTS was used both as single precursor and mixed with silane or ethylene to study the effect of the C/Si and Cl/Si ratios on growth rate and doping of the epitaxial layers. When using only MTS as precursor, the growth rate showed a linear dependence on the MTS molar fraction in the reactor up to about 100 µm/h. The growth rate dropped for C/Si < 1 but was constant for C/Si > 1. Further, the growth rate decreased with lower Cl/Si ratio.

scholarly journals Adaptation of central metabolite pools to variations in growth rate and cultivation conditions in Saccharomyces cerevisiae

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Kanhaiya Kumar ◽  
Vishwesh Venkatraman ◽  
Per Bruheim
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Growth Rate ◽  
Amino Acid ◽  
Growth Rates ◽  
Pentose Phosphate Pathway ◽  
Pentose Phosphate ◽  
Relative Reduction ◽  
Central Metabolism ◽  
Cultivation Conditions ◽  
Biological Studies

Abstract Background Saccharomyces cerevisiae is a well-known popular model system for basic biological studies and serves as a host organism for the heterologous production of commercially interesting small molecules and proteins. The central metabolism is at the core to provide building blocks and energy to support growth and survival in normal situations as well as during exogenous stresses and forced heterologous protein production. Here, we present a comprehensive study of intracellular central metabolite pool profiling when growing S. cerevisiae on different carbon sources in batch cultivations and at different growth rates in nutrient-limited glucose chemostats. The latest versions of absolute quantitative mass spectrometry-based metabolite profiling methodology were applied to cover glycolytic and pentose phosphate pathway metabolites, tricarboxylic acid cycle (TCA), complete amino acid, and deoxy-/nucleoside phosphate pools. Results Glutamate, glutamine, alanine, and citrate were the four most abundant metabolites for most conditions tested. The amino acid is the dominant metabolite class even though a marked relative reduction compared to the other metabolite classes was observed for nitrogen and phosphate limited chemostats. Interestingly, glycolytic and pentose phosphate pathway (PPP) metabolites display the largest variation among the cultivation conditions while the nucleoside phosphate pools are more stable and vary within a closer concentration window. The overall trends for glucose and nitrogen-limited chemostats were increased metabolite pools with the increasing growth rate. Next, comparing the chosen chemostat reference growth rate (0.12 h−1, approximate one-fourth of maximal unlimited growth rate) illuminates an interesting pattern: almost all pools are lower in nitrogen and phosphate limited conditions compared to glucose limitation, except for the TCA metabolites citrate, isocitrate and α-ketoglutarate. Conclusions This study provides new knowledge-how the central metabolism is adapting to various cultivations conditions and growth rates which is essential for expanding our understanding of cellular metabolism and the development of improved phenotypes in metabolic engineering.

The uptake of amino acids by mouse cells (strain LS) during growth in batch culture and chemostat culture: the influence of cell growth rate

1967 ◽  
Vol 168 (1013) ◽  
pp. 421-438 ◽  
Keyword(s):  
Amino Acids ◽  
Growth Rate ◽  
Amino Acid ◽  
Cell Growth ◽  
Glutamic Acid ◽  
Batch Culture ◽  
Amino Acid Uptake ◽  
Essential Amino Acids ◽  
Growth Yields ◽  
Acid Uptake

The uptake of thirteen essential amino acids by mouse LS cells in suspension culture was determined by bacteriological assay methods. Chemostat continuous-flow cultures were used to determine the effect of different cell growth rates on the quantitative amino acid requirements for growth. The growth yields of the cells ( Y = g cell dry weight produced/g amino acid utilized) were calculated for each of the essential amino acids. A mixture of the non-essential amino acids, serine, alanine and glycine increased the cell yield from the essential amino acids. The growth yields from nearly all the essential amino acids in batch culture were increased when glutamic acid was substituted for the glutamine in the medium. The growth yields from the amino acids in batch culture were much less at the beginning than at the end of the culture. The highest efficiencies of conversion of amino acids to cell material were obtained by chemostat culture. When glutamic acid largely replaced the glutamine in the medium the conversion of amino acid nitrogen to cell nitrogen was 100 % efficient (that is, the theoretical yield was obtained) at the optimum growth rate (cell doubling time, 43 h). The maximum population density a given amino acid mixture will support can be calculated from the data. It is concluded that in several routinely used tissue culture media the cell growth is limited by the amino acid supply. In batch culture glutamine was wasted by (1) its spontaneous decomposition to pyrrolidone carboxylic acid and ammonia, and (2) its enzymic breakdown to glutamic acid and ammonia, but also glutamine was used less efficiently than glutamic acid. Study of the influence of cell growth rate on amino acid uptake rates per unit mass of cells indicated that a marked change in amino acid metabolism occurred at a specific growth rate of 0.4 day -1 (cell doubling time, 43 h). With decrease in specific growth rate below 0.4 day -1 there was a marked stimulation of amino acid uptake rate per cell and essential amino acids were consumed increasingly for functions other than synthesis of cell material.

scholarly journals Rapid Growth of UropathogenicEscherichia coliduring Human Urinary Tract Infection

mBio ◽  
2018 ◽  
Vol 9 (2) ◽  
Author(s):  
Valerie S. Forsyth ◽  
Chelsie E. Armbruster ◽  
Sara N. Smith ◽  
Ali Pirani ◽  
A. Cody Springman ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Growth Rate ◽  
Urinary Tract ◽  
Growth Rates ◽  
High Growth ◽  
Replication Forks ◽  
Chromosomal Replication ◽  
E Coli ◽  
Tract Infections

ABSTRACTUropathogenicEscherichia coli(UPEC) strains cause most uncomplicated urinary tract infections (UTIs). These strains are a subgroup of extraintestinal pathogenicE. coli(ExPEC) strains that infect extraintestinal sites, including urinary tract, meninges, bloodstream, lungs, and surgical sites. Here, we hypothesize that UPEC isolates adapt to and grow more rapidly within the urinary tract than otherE. coliisolates and survive in that niche. To date, there has not been a reliable method available to measure their growth ratein vivo. Here we used two methods: segregation of nonreplicating plasmid pGTR902, and peak-to-trough ratio (PTR), a sequencing-based method that enumerates bacterial chromosomal replication forks present during cell division. In the murine model of UTI, UPEC strain growth was robustin vivo, matching or exceedingin vitrogrowth rates and only slowing after reaching high CFU counts at 24 and 30 h postinoculation (hpi). In contrast, asymptomatic bacteriuria (ABU) strains tended to maintain high growth ratesin vivoat 6, 24, and 30 hpi, and population densities did not increase, suggesting that host responses or elimination limited population growth. Fecal strains displayed moderate growth rates at 6 hpi but did not survive to later times. By PTR,E. coliin urine of human patients with UTIs displayed extraordinarily rapid growth during active infection, with a mean doubling time of 22.4 min. Thus, in addition to traditional virulence determinants, including adhesins, toxins, iron acquisition, and motility, very high growth ratesin vivoand resistance to the innate immune response appear to be critical phenotypes of UPEC strains.IMPORTANCEUropathogenicEscherichia coli(UPEC) strains cause most urinary tract infections in otherwise healthy women. While we understand numerous virulence factors are utilized byE. colito colonize and persist within the urinary tract, these properties are inconsequential unless bacteria can divide rapidly and survive the host immune response. To determine the contribution of growth rate to successful colonization and persistence, we employed two methods: one involving the segregation of a nonreplicating plasmid in bacteria as they divide and the peak-to-trough ratio, a sequencing-based method that enumerates chromosomal replication forks present during cell division. We found that UPEC strains divide extraordinarily rapidly during human UTIs. These techniques will be broadly applicable to measurein vivogrowth rates of other bacterial pathogens during host colonization.

High protein wheats for poultry. 1. Use in broiler diets

1971 ◽  
Vol 11 (53) ◽  
pp. 619 ◽  
Author(s):  
W Turner ◽  
GG Payne
Keyword(s):  
Amino Acids ◽  
Growth Rate ◽  
Amino Acid ◽  
Crude Protein ◽  
Maximum Level ◽  
Essential Amino Acids ◽  
High Protein ◽  
Amino Acid Supplementation ◽  
Dietary Factor ◽  
Protein Diets

High protein wheat was the sole cereal in 20 and 25 per cent crude protein broiler starter diets. On the. 25 per cent protein diet, performance was maximized without amino acid supplementation. Using high protein wheat in 20 per cent protein diets, growth rate was improved by l-lysine supplementation of 0.3 per cent. However, this growth rate was not at a maximum level. Some other dietary factor was necessary, and this did not appear to be essential amino acids, singly or in combination.

An analysis of growth of different cattle genotypes reared in different environments

1984 ◽  
Vol 103 (1) ◽  
pp. 137-153 ◽  
Author(s):  
J. E. Frisch ◽  
T. E. Vercoe
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
High Growth ◽  
Environmental Stresses ◽  
Growth Potential ◽  
Gastrointestinal Helminths ◽  
Treatment Groups ◽  
Survival And Growth ◽  
Different Levels ◽  
High Growth Potential

SummaryCalves from three breeds, Brahman, Hereford × Shorthorn (HS) and Brahman × HS (BX), were divided equally into two groups, one of which was treated every 3 weeks from birth onwards to control ticks and gastrointestinal helminths, and one of which was untreated. Mortalities, growth rates and levels of resistance to environmental stresses that affected both mortality and growth under grazing conditions were recorded for all animals up to weaning (6 months) and for all males up to 15 months of age. The Brahmans were the most and the HS were the least resistant to environmental stresses, each of which was shown to depress growth in proportion to its magnitude and to contribute to the high mortalities of the HS. All breeds responded positively to parasite control with the greatest response in both survival and growth in the HS breed and the least response in the Brahman breed.Samples of males from the various breed-treatment groups were taken into pens where they were protected from environmental stresses and fed both low-quality pasture hay and high-quality lucerne hay ad libitum. Measurements were made of fasting metabolism, maintenance requirement, voluntary food intake and gain, variables related to the growth potential of each animal. The HS animals had the highest whilst the Brahmans had the lowest values for each variable.However, despite their low growth potential, the Brahmans had the highest growtli rate, and the HS, despite their high growth potential, had the lowest growth rate, when growth was measured in the presence of all environmental stresses. When parasites were controlled, growth rates were highest for the BX, the breed with intermediate growtli potential, and did not differ between the HS and Brahmans. These interactions arose because of the different contributions of resistance to environmental stresses and growth potential to growth rate measured at the different levels of environmental stresses. The relevance of these interactions to breed evaluation and cross-breeding is considered.Growth potential and resistance to environmental stresses were negatively correlated both between and within breeds, though the latter was biased by the effects of compensation. The influence of these relationships on the likely outcome of selection for increased growth rate, both between and within breeds, is discussed.

Relationship between bone growth rate and bone tissue organization in amniotes: first test of Amprino's rule in a phylogenetic context

2010 ◽  
Vol 60 (1) ◽  
pp. 25-41 ◽  
Author(s):  
Jacques Castanet ◽  
Jorge Cubo ◽  
Laëtitia Montes
Keyword(s):  
Growth Rate ◽  
Bone Tissue ◽  
Growth Rates ◽  
Bone Growth ◽  
Phylogenetic Signal ◽  
Variation Partitioning ◽  
High Growth ◽  
Tissue Organization ◽  
Shared Ancestry ◽  
Functional Factors

AbstractA debate on the determinism (phylogenetic versus functional) of the diversity of bone histological features has centred the interest of bone comparative biologists. While some authors have noticed the presence of a phylogenetic signal in bone tissue variation, many others have argued that these characters may not include much phylogenetic information, but rather reflect functional factors. Here we quantify both components in a sample of amniotes. We hypothesize that: 1/ the observed variation is partly the outcome of shared ancestry (phylogenetic factor) and 2/ for a given quantity of bone produced, tissues formed at a rapid rate may have a higher fraction of vascular cavities than those produced at a slower rate (functional factor). Variation partitioning analyses show that the phylogeny explains a significant portion of the variation of bone vascularity (85.3%), bone growth rate also explains a significant portion of this variation (68.3%), and there is an important overlap (67.9%). Finally, an optimization through least-squares parsimony of bone growth rates onto the phylogeny shows that the most important evolutionary change may have occurred after the split between crocodiles and birds. This change may be linked to the origin of avian endothermic metabolism because high growth rates involve high protein turnover, which is very energy consuming. We conclude that the debate on the dichotomy between phylogenetic versus functional causation of bone histological diversity is misleading, because we have shown that bone vascularity has, at the same time, a functional significance and a phylogenetic signal.

scholarly journals Studies on unidentified growth factors

1974 ◽  
Vol 31 (2) ◽  
pp. 179-184 ◽  
Author(s):  
J. Bunyan ◽  
Elspeth A. Murrell ◽  
M. A. Cawthorne ◽  
B. T. Redman
Keyword(s):  
Amino Acids ◽  
Growth Rate ◽  
Amino Acid ◽  
Soya Bean ◽  
Torula Yeast ◽  
Acid Diet ◽  
Organic Growth ◽  
Organic Factor ◽  
Amino Acid Diet ◽  
Low Activity

1. Chicks at 10 d of age were given diets containing all the nutrients known to be required, with L-amino acids in place of protein. Dietary supplements were added isonitrogenously.2. Ox liver (100 g/kg) greatly improved the chicks' growth rate, whereas torula yeast (50 g/kg) was inactive. The activity of fresh moist liver was considered to be due largely to an organic factor, because of the inactivity of water and the low activity of liver ash.3. The growth rates of chicks receiving diets based upon casein and isolated soya-bean protein were significantly improved by the inclusion of 100 g fresh ox liver/kg, but not of 50 g torula yeast/kg.4. These results show that chicks receiving an amino acid diet require an organic growth factor (Progressin) that differs from the yeast factor required by rats receiving an amino acid diet.

scholarly journals Available lysine and digestible amino acid contents of proteinaceous foods of India

2012 ◽  
Vol 108 (S2) ◽  
pp. S59-S68 ◽  
Author(s):  
Shane M. Rutherfurd ◽  
Kiran Bains ◽  
Paul J. Moughan
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Protein Quality ◽  
Amino Acid Content ◽  
Essential Amino Acids ◽  
Food Ingredients ◽  
Available Lysine ◽  
Amino Acid Contents ◽  
Sulphur Amino Acids ◽  
Prepared Food

Cereals and legumes are staple foods in India and are limiting in lysine and sulphur amino acids, respectively. Available lysine loss, due to Maillard-type reactions that may occur during food preparation, exacerbates the problem of lysine deficiency particularly in cereals. Consequently, determining the contents of digestible essential amino acids, particularly lysine, is important. True ileal digestibilities of most amino acids (including total and reactive lysine) were determined for ten food ingredients and eleven foods commonly consumed in India. Semi-synthetic diets each containing either an ingredient or the prepared food as the sole protein source were formulated to contain 100 g kg− 1protein (75 g kg− 1for rice-based diets) and fed to growing rats. Titanium dioxide was included as an indigestible marker. Digesta were collected and the amino acid content (including reactive lysine) of diets and ileal digesta determined. Available (digestible reactive) lysine content ranged from 1·9–15·4 g kg− 1and 1·8–12·7 g kg− 1across the ingredients and prepared foods respectively. True ileal amino acid digestibility varied widely both across ingredients and prepared foods for each amino acid (on average 60–92 %) and across amino acids within each ingredient and prepared food (overall digestibility 31–96 %). Amino acid digestibility was low for many of the ingredients and prepared foods and consequently digestibility must be considered when assessing the protein quality of poorer quality foods. Given commonly encountered daily energy intakes for members of the Indian population, it is estimated that lysine is limiting for adults in many Indian diets.

scholarly journals Postprandial nutrient-sensing and metabolic responses after partial dietary fishmeal replacement by soyabean meal in turbot (Scophthalmus maximus L.)

2015 ◽  
Vol 115 (3) ◽  
pp. 379-388 ◽  
Author(s):  
Dandan Xu ◽  
Gen He ◽  
Kangsen Mai ◽  
Huihui Zhou ◽  
Wei Xu ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Nutrient Retention ◽  
Scophthalmus Maximus ◽  
Amino Acid Profile ◽  
Nutrient Sensing ◽  
Fish Growth ◽  
Metabolic Responses ◽  
Amino Acid Supplementation ◽  
Soyabean Meal

AbstractIn this study, we chose a carnivorous fish, turbot (Scophthalmus maximus L.), to examine its nutrient-sensing and metabolic responses after ingestion of diets with fishmeal (FM), or 45 % of FM replaced by soyabean meal (34·6 % dry diet) balanced with or without essential amino acids (EAA) to match the amino acid profile of FM diet for 30 d. After a 1-month feeding trial, fish growth, feed efficiency and nutrient retention were markedly reduced by soyabean meal-incorporated (SMI) diets. Compared with the FM diet, SMI led to a reduction of postprandial influx of free amino acids, hypoactivated target of rapamycin signalling and a hyperactivated amino acid response pathway after refeeding, a status associated with reduced protein synthesis, impaired postprandial glycolysis and lipogenesis. These differential effects were not ameliorated by matching an EAA profile of soyabean meal to that of the FM diet through dietary amino acid supplementation. Therefore, this study demonstrated that the FM diet and SMI diets led to distinct nutrient-sensing responses, which in turn modulated metabolism and determined the utilisation efficiency of diets. Our results provide a new molecular explanation for the role of nutrient sensing in the inferior performance of aquafeeds in which FM is replaced by soyabean meal.

Sign in / Sign up

Export Citation Format

Share Document