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Johannsen JC, Sørensen MT, Theil PK, Bruun TS, Farmer C, Feyera T. Optimal protein concentration in diets for sows during the transition period. J Anim Sci 2024; 102:skae082. [PMID: 38517473 PMCID: PMC11017514 DOI: 10.1093/jas/skae082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 03/21/2024] [Indexed: 03/23/2024] Open
Abstract
The aim of the present study was to determine the optimal concentration of dietary protein required in transition diets for multiparous sows that enhance the farrowing process, colostrum production, and subsequent lactation performance. Forty-eight multiparous sows were allotted to one of six dietary treatments according to body weight (290 ± 3 kg) and parity (3.8 ± 0.2) from day 108 of gestation until 24 h after the onset of farrowing. The diets were isoenergetic and contained increasing concentrations of dietary protein (expressed as standardized ileal digestible [SID] Lys) and were supplied at a daily feed supply of 3.8 kg. On day 108 of gestation and days 2, 7, 14, 21, and 28 of lactation, body weight, and back fat thickness were recorded, and blood was sampled on day 108 of gestation, at the onset of farrowing, and days 3, 10, 17, and 24 of lactation from the sows for analysis of plasma metabolites. On day 115 of gestation, urine, and feces were collected for nitrogen (N) balance. The number of liveborn and stillborn piglets and time of birth were recorded and blood from every fourth piglet was sampled at birth for blood gas analysis. Piglets were weighed individually from birth until weaning, to estimate the colostrum and milk yield of the sows. Colostrum and milk samples were collected, and their compositions were determined. On days 3 and 28 of lactation, sows were injected with deuterium oxide to estimate body composition. The N utilization was maximized when the concentration of SID Lys in the transition diet was 6.06 g/kg (P < 0.01). When urinary concentrations of urea were expressed relative to creatinine, the relative concentration of urea remained low until a dietary concentration of 6.08 g SID Lys/kg, above which the relative concentration of urea increased (P < 0.01). Stillbirth rate increased linearly with increasing SID Lys concentration in the transition diet (P < 0.001), thus the concentration of SID Lys should be kept as low as possible without impairing sow performance excessively. A carry-over effect on milk yield was observed, showing that a dietary SID Lys concentration of 5.79 g/kg during transition optimized milk production at an average yield of 13.5 kg/d (P = 0.04). Increasing loss of body fat in lactation was observed with increasing SID Lys concentration in the transition diet (P = 0.03). In conclusion, the transition diet of multiparous sows should contain 5.79 g SID Lys/kg when fed 3.8 kg/d (13.0 MJ ME/kg), for a total SID Lys intake of 22 g/d.
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Affiliation(s)
- Jakob C Johannsen
- Department of Animal and Veterinary Sciences, Aarhus University, Campus Viborg, DK-8830 Tjele, Denmark
| | - Martin T Sørensen
- Department of Animal and Veterinary Sciences, Aarhus University, Campus Viborg, DK-8830 Tjele, Denmark
| | - Peter K Theil
- Department of Animal and Veterinary Sciences, Aarhus University, Campus Viborg, DK-8830 Tjele, Denmark
| | | | - Chantal Farmer
- Agriculture and Agri-Food Canada, Sherbrooke Research and Development Centre, Sherbrooke, QC, CanadaJ1M 0C8
| | - Takele Feyera
- Department of Animal and Veterinary Sciences, Aarhus University, Campus Viborg, DK-8830 Tjele, Denmark
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Weiler M, Hertzler SR, Dvoretskiy S. Is It Time to Reconsider the U.S. Recommendations for Dietary Protein and Amino Acid Intake? Nutrients 2023; 15:838. [PMID: 36839196 PMCID: PMC9963165 DOI: 10.3390/nu15040838] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/06/2023] [Accepted: 01/30/2023] [Indexed: 02/10/2023] Open
Abstract
Since the U.S. Institute of Medicine's recommendations on protein and amino acid intake in 2005, new information supports the need to re-evaluate these recommendations. New lines of evidence include: (1) re-analysis/re-interpretation of nitrogen balance data; (2) results from indicator amino acid oxidation studies; (3) studies of positive functional outcomes associated with protein intakes higher than recommended; (4) dietary guidance and protein recommendations from some professional nutrition societies; and (5) recognition that the synthesis of certain dispensable amino acids may be insufficient to meet physiological requirements more often than previously understood. The empirical estimates, theoretical calculations and clinical functional outcomes converge on a similar theme, that recommendations for intake of protein and some amino acids may be too low in several populations, including for older adults (≥65 years), pregnant and lactating women, and healthy children older than 3 years. Additional influential factors that should be considered are protein quality that meets operational sufficiency (adequate intake to support healthy functional outcomes), interactions between protein and energy intake, and functional roles of amino acids which could impact the pool of available amino acids for use in protein synthesis. Going forward, the definition of "adequacy" as it pertains to protein and amino acid intake recommendations must take into consideration these critical factors.
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Affiliation(s)
- Mary Weiler
- Scientific and Medical Affairs, Abbott Nutrition, 2900 Easton Square Place, Columbus, OH 43219, USA
| | - Steven R. Hertzler
- Scientific and Medical Affairs, Abbott Nutrition, 2900 Easton Square Place, Columbus, OH 43219, USA
| | - Svyatoslav Dvoretskiy
- Department of Kinesiology and Community Health, University of Illinois, Urbana-Champaign, IL 61801, USA
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3
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Ennis MA, Rasmussen BF, Lim K, Ball RO, Pencharz PB, Courtney-Martin G, Elango R. Dietary phenylalanine requirements during early and late gestation in healthy pregnant women. Am J Clin Nutr 2020; 111:351-359. [PMID: 31758682 PMCID: PMC6997087 DOI: 10.1093/ajcn/nqz288] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Accepted: 10/28/2019] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Phenylalanine is an indispensable amino acid and, via tyrosine, is the precursor for the neurotransmitters dopamine, norepinephrine, and epinephrine. Currently, dietary requirements for phenylalanine during pregnancy are unknown. OBJECTIVES This study's aim was to determine phenylalanine requirements (in the presence of excess tyrosine) during early and late gestation using direct amino acid oxidation (DAAO; with l-[1-13C]phenylalanine) and indicator amino acid oxidation (IAAO; with l-[1-13C]leucine). METHODS Twenty-three healthy women (age: 30.4 ± 3.1 y, mean ± SD) were studied at a range of phenylalanine intakes (5.5-30.5 mg · kg-1 · d-1 in early and late pregnancy using DAAO, and 2.5-30.5 mg · kg-1 · d-1 in late pregnancy using IAAO) for a total of 76 study days. Test intakes were provided as 8 isocaloric and isonitrogenous meals with 1.5 g · kg-1 · d-1 protein and energy at 1.7 times the measured resting energy expenditure. Breath samples were analyzed on an isotope ratio mass spectrometer for 13C enrichment. Phenylalanine requirement was determined using a 2-phase linear regression crossover model to identify a breakpoint in 13CO2 production (representing the mean requirement) in response to phenylalanine intakes. RESULTS Phenylalanine requirement during early pregnancy was determined to be 15 mg · kg-1 · d-1 (95% CI: 10.4, 19.9 mg · kg-1 · d-1); during late pregnancy, it was determined to be 21 mg · kg-1 · d-1 by DAAO (95% CI: 17.4, 24.7 mg · kg-1 · d-1) and IAAO (95% CI: 10.5, 32.2 mg · kg-1 · d-1). CONCLUSIONS Our results suggest a higher requirement (40%) for phenylalanine during late pregnancy than during early pregnancy. Moreover, the early pregnancy requirements are higher than the previous adult male requirement (9.1 mg · kg-1 · d-1; 95% CI: 4.6, 13.6 mg · kg-1 · d-1), although the 95% CIs overlap. Both DAAO and IAAO methods provided similar breakpoints in late pregnancy, showing that the DAAO method was appropriate even though low phenylalanine intakes could not be tested. These results have potential implications for gestation stage-specific dietary phenylalanine recommendations in future.This trial was registered at clinicaltrials.gov as NCT02669381.
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Affiliation(s)
- Madeleine A Ennis
- BC Children's Hospital Research Institute, BC Children's Hospital, Vancouver, British Columbia, Canada
- Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Betina F Rasmussen
- BC Children's Hospital Research Institute, BC Children's Hospital, Vancouver, British Columbia, Canada
- Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kenneth Lim
- BC Children's Hospital Research Institute, BC Children's Hospital, Vancouver, British Columbia, Canada
- Department of Obstetrics and Gynecology, BC Women's Hospital, Vancouver, British Columbia, Canada
| | - Ronald O Ball
- Department of Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Paul B Pencharz
- Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, Canada
- Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada
| | - Glenda Courtney-Martin
- Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, Canada
- Faculty of Kinesiology, University of Toronto, Toronto, Ontario, Canada
| | - Rajavel Elango
- BC Children's Hospital Research Institute, BC Children's Hospital, Vancouver, British Columbia, Canada
- Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
- School of Population and Public Health, University of British Columbia, Vancouver, British Columbia, Canada
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Gu C, Mao X, Chen D, Yu B, Yang Q. Isoleucine Plays an Important Role for Maintaining Immune Function. Curr Protein Pept Sci 2019; 20:644-651. [PMID: 30843485 DOI: 10.2174/1389203720666190305163135] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 12/30/2018] [Accepted: 01/10/2019] [Indexed: 12/16/2022]
Abstract
Branched chain amino acids are the essential nutrients for humans and many animals. As functional amino acids, they play important roles in physiological functions, including immune functions. Isoleucine, as one of the branched chain amino acids, is also critical in physiological functions of the whole body, such as growth, immunity, protein metabolism, fatty acid metabolism and glucose transportation. Isoleucine can improve the immune system, including immune organs, cells and reactive substances. Recent studies have also shown that isoleucine may induce the expression of host defense peptides (i.e., β-defensins) that can regulate host innate and adaptive immunity. In addition, isoleucine administration can restore the effect of some pathogens on the health of humans and animals via increasing the expression of β-defensins. Therefore, the present review will emphatically discuss the effect of isoleucine on immunity while summarizing the relationship between branched chain amino acids and immune functions.
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Affiliation(s)
- Changsong Gu
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease- Resistance Nutrition, Chinese Ministry of Education, Chengdu, China
| | - Xiangbing Mao
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease- Resistance Nutrition, Chinese Ministry of Education, Chengdu, China
| | - Daiwen Chen
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease- Resistance Nutrition, Chinese Ministry of Education, Chengdu, China
| | - Bing Yu
- Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, China.,Key Laboratory of Animal Disease- Resistance Nutrition, Chinese Ministry of Education, Chengdu, China
| | - Qing Yang
- Department of Animal Science, Oklahoma State University, Stillwater, Oklahoma, KS, United States
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Payne M, Stephens T, Lim K, Ball RO, Pencharz PB, Elango R. Lysine Requirements of Healthy Pregnant Women are Higher During Late Stages of Gestation Compared to Early Gestation. J Nutr 2018; 148:94-99. [PMID: 29378056 DOI: 10.1093/jn/nxx034] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 11/07/2017] [Indexed: 11/13/2022] Open
Abstract
Background Lysine is the first limiting amino acid in cereal proteins and is found mainly in animal-derived products. Current Dietary Reference Intake (DRI) recommendations extrapolate lysine requirements during pregnancy from nonpregnant adult data, and may underestimate true requirements. Objective Our objective is to define a quantitative lysine requirement in healthy pregnant women and to determine whether requirements vary between 2 phases of gestation. Methods Fourteen pregnant women in early (12-19 wk) and 19 women in late (33-39 wk) gestation were studied using the indicator amino acid oxidation technique. Individual lysine intakes (6-84 mg · kg-1 · d-1, deficient to excess) were tested on each study day as a crystalline amino acid mixture based on egg protein composition. Isonitrogenous diets maintained protein intake at 1.5 g · kg-1 · d-1 and calorie intake at 1.7 times resting energy expenditure during each study day. Phenylalanine and tyrosine intakes were held constant across all lysine intakes. Breath and urine samples were collected at baseline and isotopic steady state. Lysine requirements were determined by measuring the oxidation of L-[1-13C]-phenylalanine to 13CO2 (F13CO2). Biphase linear regression crossover analysis was used to determine a breakpoint (which represents the estimated average requirement, EAR) in F13CO2. Results The EAR for lysine during early gestation was determined to be 36.6 mg · kg-1 · d-1 (R2 = 0.484, upper 95% CI = 46.2 mg · kg-1 · d-1), similar to an earlier adult requirement of 36 mg · kg-1 · d-1. The EAR for lysine during late gestation was determined to be 50.3 mg · kg-1 · d-1 (R2 = 0.664, upper 95% CI = 60.4 mg · kg-1 · d-1), 23% higher than the current pregnancy DRI EAR recommendation of 41 mg · kg-1 · d-1. Conclusions Our results suggest that lysine requirements are higher during late gestation compared to early gestation, and that current dietary lysine recommendations during late stages of pregnancy may be underestimated. The results have implications for populations consuming cereal-based diets as their primary source of protein. This trial was registered at clinicaltrials.gov as NCT01776931.
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Affiliation(s)
- Magdalene Payne
- BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada.,Pediatrics, Obstetrics and Gynecology, and School of Population and Public Health, University of British Columbia, British Columbia, Canada
| | - Trina Stephens
- BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada.,Pediatrics, Obstetrics and Gynecology, and School of Population and Public Health, University of British Columbia, British Columbia, Canada
| | - Kenneth Lim
- BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada.,Obstetrics and Gynecology, and School of Population and Public Health, University of British Columbia, British Columbia, Canada
| | - Ronald O Ball
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Paul B Pencharz
- The Research Institute, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, Canada
| | - Rajavel Elango
- BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada.,Pediatrics, Obstetrics and Gynecology, and School of Population and Public Health, University of British Columbia, British Columbia, Canada.,School of Population and Public Health, University of British Columbia, British Columbia, Canada
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6
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Abstract
Protein forms an essential component of a healthy diet in humans to support both growth and maintenance. During pregnancy, an exceptional stage of life defined by rapid growth and development, adequate dietary protein is crucial to ensure a healthy outcome. Protein deposition in maternal and fetal tissues increases throughout pregnancy, with most occurring during the third trimester. Dietary protein intake recommendations are based on factorial estimates because the traditional method of determining protein requirements, nitrogen balance, is invasive and undesirable during pregnancy. The current Estimated Average Requirement and RDA recommendations of 0.88 and 1.1 g · kg(-1) · d(-1), respectively, are for all stages of pregnancy. The single recommendation does not take into account the changing needs during different stages of pregnancy. Recently, with the use of the minimally invasive indicator amino acid oxidation method, we defined the requirements to be, on average, 1.2 and 1.52 g · kg(-1) · d(-1) during early (∼16 wk) and late (∼36 wk) stages of pregnancy, respectively. Although the requirements are substantially higher than current recommendations, our values are ∼14-18% of total energy and fit within the Acceptable Macronutrient Distribution Range. Using swine as an animal model we showed that the requirements for several indispensable amino acids increase dramatically during late gestation compared with early gestation. Additional studies should be conducted during pregnancy to confirm the newly determined protein requirements and to determine the indispensable amino acid requirements during pregnancy in humans.
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Affiliation(s)
- Rajavel Elango
- Child and Family Research Institute, Vancouver, British Columbia, Canada; Department of Pediatrics and School of Population and Public Health, University of British Columbia, Vancouver, British Columbia, Canada; and
| | - Ronald O Ball
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
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7
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Adaptation of in vivo amino acid kinetics facilitates increased amino acid availability for fetal growth in adolescent and adult pregnancies alike. Br J Nutr 2014; 112:1779-86. [PMID: 25322974 DOI: 10.1017/s000711451400292x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
During pregnancy, adult women with a normal BMI synthesise extra amino acids after an overnight fast by increasing body protein breakdown and decreasing amino acid oxidation. It is not known whether adolescent girls can make these adaptations during pregnancy. The present study aimed to measure and compare the protein, glutamine and alanine kinetics of adult women and adolescent girls at early-, mid- and late-pregnancy. Kinetics were measured in the overnight fasted state using intravenous infusions of 13C-leucine, 15N-glutamine and 15N-alanine in ten adults and twenty adolescents aged 14-17 years in the first and second trimesters (phase 1 study) and infusions of 13C-leucine and 15N2-urea in ten adults and eleven adolescents aged 16-17 years in the first and third trimesters (phase 2 study). In phase 1 study, there were no significant differences between the groups with regard to any of the kinetic parameters measured. In both groups, leucine flux increased (P< 0.05), the percentage of leucine flux oxidised decreased (P< 0.05) and non-oxidative leucine disposal to protein synthesis increased (P< 0.05) from the first to the second trimester. In phase2 study, leucine flux was significantly slower (P< 0.05) in the adult group than in the adolescent group during both trimesters, and whole-body leucine flux and non-oxidative leucine disposal increased significantly in the adolescent group (P< 0.05, respectively) and were higher in the adult group from the first to the third trimester. These results suggest that similar to their adult counterparts after an overnight fast, adolescent girls with a normal BMI provide extra amino acids required for net protein deposition during pregnancy by increasing protein breakdown and decreasing amino acid oxidation.
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Franco DJ, Josephson JK, Moehn S, Pencharz PB, Ball RO. Tryptophan requirement of pregnant sows1. J Anim Sci 2014; 92:4457-65. [DOI: 10.2527/jas.2013-7023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- D. J. Franco
- Department of Agriculture, Food and Nutritional Sciences, University of Alberta, Edmonton, AB T6G 2P5, Canada
| | - J. K. Josephson
- Department of Agriculture, Food and Nutritional Sciences, University of Alberta, Edmonton, AB T6G 2P5, Canada
| | - S. Moehn
- Department of Agriculture, Food and Nutritional Sciences, University of Alberta, Edmonton, AB T6G 2P5, Canada
| | - P. B. Pencharz
- Research Institute, Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
| | - R. O. Ball
- Department of Agriculture, Food and Nutritional Sciences, University of Alberta, Edmonton, AB T6G 2P5, Canada
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Mastro LM, Adams AA, Urschel KL. Whole-body phenylalanine kinetics and skeletal muscle protein signaling in horses with pituitary pars intermedia dysfunction. Am J Vet Res 2014; 75:658-67. [PMID: 24959733 DOI: 10.2460/ajvr.75.7.658] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To compare whole-body phenylalanine kinetics and the abundance of factors in signaling pathways associated with skeletal muscle protein synthesis and protein breakdown between horses with pituitary pars intermedia dysfunction (PPID) and age-matched control horses without PPID. ANIMALS 12 aged horses (6 horses with PPID and 6 control horses; mean age, 25.0 and 25.7 years, respectively). PROCEDURES Plasma glucose, insulin, and amino acids concentrations were determined before and 90 minutes after feeding. Gluteal muscle biopsy samples were obtained from horses 90 minutes after feeding, and the abundance and activation of factors involved in signaling pathways of muscle protein synthesis and breakdown were determined. The next day, horses received a priming dose and 2 hours of a constant rate infusion of (13)C sodium bicarbonate followed by a priming dose and 4 hours of a constant rate infusion of 1-(13)C phenylalanine IV; whole-body protein synthesis was determined. RESULTS Plasma glucose and insulin concentrations were higher after feeding than they were before feeding for both groups of horses; however, no significant postprandial increase in plasma amino acids concentrations was detected for either group. Phenylalanine flux, oxidation, release from protein breakdown, and nonoxidative disposal were not significantly different between groups. No significant effect of PPID status was detected on the abundance or activation of positive or negative regulators of protein synthesis or positive regulators of protein breakdown. CONCLUSIONS AND CLINICAL RELEVANCE Results of this study suggested that whole-body phenylalanine kinetics and the postprandial activation of signaling pathways that regulate protein synthesis and breakdown in muscles were not affected by PPID status alone in aged horses.
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Affiliation(s)
- Laurel M Mastro
- Departments of Animal and Food Sciences, College of Agriculture, Food and the Environment, University of Kentucky, Lexington, KY 40546
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Goodband RD, Tokach MD, Goncalves MAD, Woodworth JC, Dritz SS, DeRouchey JM. Nutritional enhancement during pregnancy and its effects on reproduction in swine. Anim Front 2013. [DOI: 10.2527/af.2013-0036] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- R. D. Goodband
- Department of Animal Sciences and Industry, College of Agriculture, Kansas State University, Manhattan, KS, USA
| | - M. D. Tokach
- Department of Animal Sciences and Industry, College of Agriculture, Kansas State University, Manhattan, KS, USA
| | - M. A. D. Goncalves
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - J. C. Woodworth
- Department of Animal Sciences and Industry, College of Agriculture, Kansas State University, Manhattan, KS, USA
| | - S. S. Dritz
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - J. M. DeRouchey
- Department of Animal Sciences and Industry, College of Agriculture, Kansas State University, Manhattan, KS, USA
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