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Albuquerque J, Neves AR, Van Dorpe I, Fonseca AJM, Cabrita ARJ, Reis S. Production of rumen- and gastrointestinal-resistant nanoparticles to deliver lysine to dairy cows. Sci Rep 2023; 13:16667. [PMID: 37794129 PMCID: PMC10550922 DOI: 10.1038/s41598-023-43865-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Accepted: 09/29/2023] [Indexed: 10/06/2023] Open
Abstract
Supplementing diets with rumen-protected lysine is a common strategy to meet the nutritional needs of high-producing dairy cows. This work addressed two separate but crucial issues: the lysine protection degree across the entire digestive tract as well as the production scalability of the proposed delivery systems. This was achieved by evaluating, in vitro or ex vivo, previously developed rumen-resistant lipid nanoparticles regarding their stability in the digestive tract and in the bloodstream of the dairy cow as well as how their production could be scaled-up. Results showed that the developed nanoparticles were able to resist digestion along the digestive tract but were degraded in the blood over 24 h. Thus, releasing their content to be used by the animal. In vitro viability assays were also performed, with the nanoparticles being found not to be inherently toxic when using nanoparticle concentrations up to 1 mg/mL. Results showed that neither the purity of the used lipids nor the production method significantly altered the nanoparticles' properties or their ruminal resistance. Furthermore, the shelf-life of these nanoparticles was assessed, and they were found to retain their properties and remain usable after at least 1 month of storage. Moreover, a pilot-scale production allowed the production of nanoparticles with similar properties to the previous ones made using standard methods. To summarize, the proposed rumen-resistant nanoparticles presented potential as orally ingested lysine delivery systems for dairy cattle supplementation, being capable of a large-scale production using cheaper components while maintaining their properties and without any efficiency loss. It should however be noted that these results were obtained mainly in vitro and further in vivo bioavailability and production experiments are needed before this technology can be confirmed as a viable way of delivering lysine to dairy cows.
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Affiliation(s)
- João Albuquerque
- LAQV, REQUIMTE, Department of Chemical Sciences, FFUP, Rua Jorge Viterbo Ferreira n.º 228, 4050-313, Porto, Portugal
- School of Medicine and Biomedical Sciences (ICBAS), University of Porto, Rua Jorge Viterbo Ferreira n.º 228, 4050-313, Porto, Portugal
| | - Ana R Neves
- LAQV, REQUIMTE, Department of Chemical Sciences, FFUP, Rua Jorge Viterbo Ferreira n.º 228, 4050-313, Porto, Portugal
- CQM+-Centro de Química da Madeira, Universidade da Madeira, Campus da Penteada, 9020-105, Funchal, Portugal
| | - Ingrid Van Dorpe
- PREMIX-Especialidades Agrícolas e Pecuárias. Lda, Parque Indústrial II-Neiva, 4935-232, Viana do Castelo, Portugal
| | - António J M Fonseca
- LAQV, REQUIMTE, School of Medicine and Biomedical Sciences (ICBAS), University of Porto, Rua Jorge Viterbo Ferreira n.º 228, 4050-313, Porto, Portugal
| | - Ana R J Cabrita
- LAQV, REQUIMTE, School of Medicine and Biomedical Sciences (ICBAS), University of Porto, Rua Jorge Viterbo Ferreira n.º 228, 4050-313, Porto, Portugal.
| | - Salette Reis
- LAQV, REQUIMTE, Department of Chemical Sciences, FFUP, Rua Jorge Viterbo Ferreira n.º 228, 4050-313, Porto, Portugal
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2
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Glutamate Efflux across the Blood–Brain Barrier: New Perspectives on the Relationship between Depression and the Glutamatergic System. Metabolites 2022; 12:metabo12050459. [PMID: 35629963 PMCID: PMC9143347 DOI: 10.3390/metabo12050459] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/11/2022] [Accepted: 05/17/2022] [Indexed: 02/04/2023] Open
Abstract
Depression is a significant cause of disability and affects millions worldwide; however, antidepressant therapies often fail or are inadequate. Current medications for treating major depressive disorder can take weeks or months to reach efficacy, have troubling side effects, and are limited in their long-term capabilities. Recent studies have identified a new set of glutamate-based approaches, such as blood glutamate scavengers, which have the potential to provide alternatives to traditional antidepressants. In this review, we hypothesize as to the involvement of the glutamate system in the development of depression. We identify the mechanisms underlying glutamate dysregulation, offering new perspectives on the therapeutic modalities of depression with a focus on its relationship to blood–brain barrier (BBB) permeability. Ultimately, we conclude that in diseases with impaired BBB permeability, such as depression following stroke or traumatic brain injury, or in neurogenerative diseases, the glutamate system should be considered as a pathway to treatment. We propose that drugs such as blood glutamate scavengers should be further studied for treatment of these conditions.
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3
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Hanigan MD, Daley VL. Use of Mechanistic Nutrition Models to Identify Sustainable Food Animal Production. Annu Rev Anim Biosci 2020; 8:355-376. [PMID: 31730368 DOI: 10.1146/annurev-animal-021419-083913] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
To feed people in the coming decades, an increase in sustainable animal food production is required. The efficiency of the global food production system is dependent on the knowledge and improvement of its submodels, such as food animal production. Scientists use statistical models to interpret their data, but models are also used to understand systems and to integrate their components. However, empirical models cannot explain systems. Mechanistic models yield insight into the mechanism and provide guidance regarding the exploration of the system. This review offers an overview of models, from simple empirical to more mechanistic models. We demonstrate their applications to amino acid transport, mass balance, whole-tissue metabolism, digestion and absorption, growth curves, lactation, and nutrient excretion. These mechanistic models need to be integrated into a full model using big data from sensors, which represents a new challenge. Soon, training in quantitative and computer science skills will be required to develop, test, and maintain advanced food system models.
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Affiliation(s)
- Mark D Hanigan
- Department of Dairy Science, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA; ,
| | - Veridiana L Daley
- Department of Dairy Science, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA; , .,National Animal Nutrition Program (NANP), Department of Animal & Food Sciences, University of Kentucky, Lexington, Kentucky 40546, USA
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4
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Yoder PS, Huang X, Teixeira IA, Cant JP, Hanigan MD. Effects of jugular infused methionine, lysine, and histidine as a group or leucine and isoleucine as a group on production and metabolism in lactating dairy cows. J Dairy Sci 2020; 103:2387-2404. [PMID: 31954565 DOI: 10.3168/jds.2019-17082] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Accepted: 11/04/2019] [Indexed: 01/07/2023]
Abstract
Essential AA (EAA), particularly leucine, isoleucine, methionine, and histidine, possess signaling properties for promoting cellular anabolic metabolism, whereas methionine, lysine, and histidine are considered also to be substrate limiting AA. The objective of this study was to evaluate production responses to supplementation of 2 AA groups in a 2 × 2 factorial design. Eight cows (99 ± 18 days in milk) were assigned to 4 jugular infusion treatments consisting of saline (CON), methionine plus lysine plus histidine (MKH), isoleucine plus leucine (IL), or MKH plus IL, in a replicated 4 × 4 Latin square design. Periods were 18 d in length, comprising 8 d of rest followed by 10 d of jugular infusion. Daily infusion amounts were 21 g of methionine, 38 g of lysine, 20 g of histidine, 50 g of leucine, and 22 g of isoleucine. Cows were ad libitum fed a common diet consisting of 15.2% crude protein and 1.61 Mcal/kg NEL on a dry matter basis that was predicted to meet rumen degradable protein requirements but was 15% deficient in metabolizable protein. Milk and energy-corrected milk yields increased by 2.3 kg/d and 1.9 kg/d, respectively, with infused IL, and no change was observed for MKH. Milk protein concentration increased by 0.13 percentage units for MKH, whereas milk protein yield increased for both MKH and IL by 84 g/d and 64 g/d, respectively. The milk protein yield increase for MKH+IL was 145 g/d versus CON. Gross feed efficiency tended to increase with IL infusion, and N efficiency tended to increase with MKH infusion. Aggregate arterial EAA concentrations less Met, Lys, and His declined by 7.2% in response to MKH infusion. Arterial EAA less Ile and Leu also declined by 6.2% in response to IL infusion. Net total AA (TAA) and EAA uptake by the udder tended to increase in response to MKH infusion, whereas mammary blood flow increased in response to IL infusion, but TAA and EAA net uptakes were unaffected. Apparent udder affinity increased for TAA and EAA less Met, Lys, and His in response to MKH infusion, whereas affinity for EAA less Ile and Leu increased for IL infusion. Venous Met and Leu concentrations increased by 192% and 35% from the MKH and IL infusions, respectively, compared with CON, which indicates that intracellular concentration of these EAA changed substantially. Increases in milk protein yield were observed from 2 groups of amino acids independently and additively, which contradicts the single limiting amino acid theory that a single EAA will limit milk protein yield.
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Affiliation(s)
- P S Yoder
- Department of Dairy Science, Virginia Tech, Blacksburg 24061; Perdue AgriBusiness LLC, Salisbury, MD 21804
| | - X Huang
- Department of Dairy Science, Virginia Tech, Blacksburg 24061
| | | | - J P Cant
- Department of Animal Biosciences, University of Guelph, Ontario, N1G 2W1 Canada
| | - M D Hanigan
- Department of Dairy Science, Virginia Tech, Blacksburg 24061.
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5
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Leno B, Ryan C, Stokol T, Kirk D, Zanzalari K, Chapman J, Overton T. Effects of prepartum dietary cation-anion difference on aspects of peripartum mineral and energy metabolism and performance of multiparous Holstein cows. J Dairy Sci 2017; 100:4604-4622. [DOI: 10.3168/jds.2016-12221] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 02/02/2017] [Indexed: 11/19/2022]
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6
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Šamanc H, Kirovski D, Lakić N, Celeska I, Bojković-Kovačević S, Sladojević Ž, Ivanov I. A comparison of the concentrations of energy-balance-related variables in jugular and mammary vein blood of dairy cows with different milk yield. Acta Vet Hung 2014; 62:52-63. [PMID: 24334081 DOI: 10.1556/avet.2013.055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The aim of this study was to compare the concentrations of blood variables obtained simultaneously from the jugular and mammary veins of dairy cows. Eighty Holstein cows were divided into four equal groups: dry, low- (LY), medium- (MY) and high-yielding (HY). Blood insulin, glucose, non-esterified fatty acid (NEFA), beta-hydroxybutyrate (BHBA) and urea concentrations were measured. The jugular and mammary vein (J/M) ratio between concentrations of each variable was calculated. Differences between the groups of cows in concentrations of variables in the jugular vein were not in accordance with those obtained for the mammary vein. J/M values for insulin and glucose concentrations were above 1.0 in all groups of cows. The ratios for NEFA and BHBA concentrations were under or equal to 1.0 in dry and LY cows but above 1.0 in the MY and HY groups, indicating that in MY and HY cows those metabolites are apparently utilised by the mammary gland. J/M values for urea were above 1.0 in dry and LY cows but less than 1.0 in groups MY and HY, indicating that in the latter case urea is apparently released by the mammary gland. In conclusion, J/M for NEFA, BHBA and urea may be useful for estimation of the critical point when the mammary gland receives insufficient energy precursors for its current activity.
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Affiliation(s)
- Horea Šamanc
- 1 University of Belgrade Department of Farm Animal Diseases Bulevar Oslobođenja 18 Belgrade 11 000 Serbia
| | - Danijela Kirovski
- 2 University of Belgrade Department of Physiology and Biochemistry Bulevar Oslobođenja 18 Belgrade 11 000 Serbia
| | - Nada Lakić
- 3 University of Belgrade Department of Agroeconomy, Faculty of Agriculture Belgrade Serbia
| | - Irena Celeska
- 4 Faculty of Veterinary Medicine Department of Pathophysiology Skopje Macedonia
| | | | - Željko Sladojević
- 6 Veterinary Station ‘Veterina System Sladojević’ Gradiška Republic of Srpska, Bosnia and Herzegovina
| | - Ivan Ivanov
- 1 University of Belgrade Department of Farm Animal Diseases Bulevar Oslobođenja 18 Belgrade 11 000 Serbia
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7
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Nielsen TT, Pierzynowski SG, Børsting CF, Nielsen MO, Jakobsen K. Catheterization of Arteria Epigastrica Cranialis, Measurement of Nutrient Arteriovenous Differences and Evaluation of Daily Plasma Flow Across the Mammary Gland of Lactating Sows. ACTA AGR SCAND A-AN 2010. [DOI: 10.1080/090647002320229365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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8
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Tagari H, Webb K, Theurer B, Huber T, DeYoung D, Cuneo P, Santos J, Simas J, Sadik M, Alio A, Lozano O, Delgado-Elorduy A, Nussio L, Bittar C, Santos F. Mammary Uptake, Portal-Drained Visceral Flux, and Hepatic Metabolism of Free and Peptide-Bound Amino Acids in Cows Fed Steam-Flaked or Dry-Rolled Sorghum Grain Diets. J Dairy Sci 2008; 91:679-97. [DOI: 10.3168/jds.2007-0629] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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9
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Li B, Wang Z, Li F, Lin X. Milk fat content was changed by ruminal infusion of mixed VFAs solutions with different acetate/propionate ratios in lactating goats. Small Rumin Res 2007. [DOI: 10.1016/j.smallrumres.2006.07.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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10
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Savary IC, Hoskin SO, Dennison N, Lobley GE. Lysine metabolism across the hindquarters of sheep; effect of intake on transfers from plasma and red blood cells. Br J Nutr 2007; 85:565-73. [PMID: 11348571 DOI: 10.1079/bjn2000318] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Both plasma and red blood cells contain amino acids (AA), but the relative amount of AA transferred from each vascular compartment to the tissues remains unclear. For splanchnic tissues, the relative transfers between the plasma, the red blood cells and the tissues may vary with nutritional state, but whether the same situation pertains for other tissues is not known. The current study focused on the transfer of lysine from plasma and red blood cells across the hindquarters of sheep offered four levels of intakes (0.5, 1.0, 1.5 and 2.5×maintenance energy). This design, coupled with use of [U-13C]lysine as tracer, also allowed the effect of intake on protein kinetics to be examined. At all intakes, the concentration of lysine in the sheep’ red blood cells exceeded that in plasma by 50 % (P<0.001), while the distribution of labelled lysine between the plasma and the red blood cells was 0.71:0.29. Net lysine uptake by the hindquarters increased in a linear manner (P<0.001) with intake, with more than 90 % extracted from the plasma. Free lysine enrichments in plasma from the posterior vena cava were less than that from the artery (P<0.001), but those in red blood cells were not different between the artery and vein. The red blood cells thus play a minor role in the transfers to and from the hindquarter tissues, regardless of intake. Based on plasma transfers and the enrichment of lysine in arterial plasma, hindquarter protein synthesis increased linearly with intake (P<0.001). In contrast, protein breakdown was unaffected by intake. The contribution of hindquarter protein synthesis to whole-body lysine flux remained unchanged with intake (18–20 %).
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Affiliation(s)
- I C Savary
- INRA-Theix, 63122 St Genès Champanelle, France.
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11
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Tagari H, Webb K, Theurer B, Huber T, DeYoung D, Cuneo P, Santos JEP, Simas J, Sadik M, Alio A, Lozano O, Delgado-Elorduy A, Nussio L, Nussio C, Santos F. Portal Drained Visceral Flux, Hepatic Metabolism, and Mammary Uptake of Free and Peptide-Bound Amino Acids and Milk Amino Acid Output in Dairy Cows Fed Diets Containing Corn Grain Steam Flaked at 360 or Steam Rolled at 490 g/L. J Dairy Sci 2004; 87:413-30. [PMID: 14762085 DOI: 10.3168/jds.s0022-0302(04)73181-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Objectives were to measure net fluxes of free (FAA) and peptide bound amino acids (AA) (PBAA) across portal-drained viscera (PDV), liver, splanchnic, and mammary tissues, and of milk AA output of lactating Holstein cows (n = 6, 109 +/- 9 d in milk) as influenced by flaking density of corn grain. Cows were fed alfalfa-based total mixed ration (TMR) containing 40% steam-flaked (SFC) or steam-rolled corn (SRC) grain. The TMR were offered at 12-h intervals in a crossover design. Six sets of blood samples were obtained from indwelling catheters in portal, hepatic, and mammary veins and mesenteric or costoabdominal arteries every 2 h from each cow and diet. Intake of dry matter (18.4 +/- 0.4 kg/d), N, and net energy for lactation were not altered by corn processing. Milk and milk crude protein yields (kg/12-h sampling) were 14.2 vs. 13.5 and 0.43 vs. 0.39 for cows fed SFC or SRC, respectively. The PDV flux of total essential FAA was greater (571.2 vs. 366.4 g/12 h, SEM 51.4) in cows fed SFC. The PDV flux of total essential PBAA was 69.3 +/- 10.8 and 51.5 +/- 13.2 g/12 h for cows fed SFC and SRC, respectively, and differed from zero, but fluxes of individual PBAA rarely differed between treatments. Liver flux of essential FAA was greater in cows fed SRC, but only the PBAA flux in cows fed SRC differed from zero. Splanchnic flux of FAA and PBAA followed the pattern of PDV flux, but variation was greater. Mammary uptake (g/12 h) of total essential FAA was greater in cows fed SFC than SRC (224.6 vs. 198.3, SEM 7.03). Mammary uptake of essential PBAA was 25.0 vs. 15.1, SEM 5.2, g/12 h for cows fed SFC or SRC, respectively, and differed from zero in half of the PBAA. Milk output of EAA was 187.8 vs 175.4, SEM 4.4 g/12 h in cows fed SFC and SRC, respectively, and output of most essential AA consistently tended to be greater in cows fed SFC. It is apparent that PBAA comprise a portion of total AA flux across PDV and are affected by grain processing. Further, this pool supplies an important component of AA taken up by the mammary gland. Quantifying the contribution of PBAA may improve diet formulation with respect to intestinal absorption and mammary uptake of AA.
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Affiliation(s)
- H Tagari
- Department of Animal Sciences, Faculty of Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel 76100.
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12
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Thivierge MC, Petitclerc D, Bernier JF, Couture Y, Lapierre HD. Variations in mammary protein metabolism during the natural filling of the udder with milk over a 12-h period between two milkings: leucine kinetics. J Dairy Sci 2002; 85:2974-85. [PMID: 12487463 DOI: 10.3168/jds.s0022-0302(02)74383-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
To define the temporal variations of whole body and mammary leucine kinetics over a 12-h period between two milkings, we used two groups of four Holstein cows, one in their second and the other in their third or fourth lactation. Cows were infused with L-[1-13C]leucine during the 12-h interval between two milkings. Blood was sampled every 30 min during that period from arterial and mammary sources. Timeafter milking did not affect whole body irreversible loss rate of leucine but affected whole body leucine oxidation, which broadly followed variations in arterial plasma leucine concentration. Similarly, mammary leucine irreversible loss rate and leucine used for protein synthesis were not affected by time after milking. Leucine oxidation by the mammary gland was, however, affected by time after milking. It increased by 15% from the first 2-h period to the following 4-h period and then decreased by 13% over the following 2-h period. A 21% increase in leucine oxidation was observed from 8 to 10 h after milking, and then it decreased by 26% over the last 2-h period. Protein degradation expressed as percentage of mammary leucine flux followed a similar temporal pattern. Leucine used for protein synthesis by the mammary gland was unaltered over time after milking, suggesting that the increased availability of leucine resulting from mammary protein breakdown would increase intracellular concentrations of leucine, which would have favored its catabolism. Overall, these results confirm the high metabolic activity of the mammary gland, as protein synthesis by the mammary gland averaged 43% of whole body protein synthesis.
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Affiliation(s)
- M C Thivierge
- Dpartement des sciences animales, Pavillon Paul-Comtols, Université Laval, Sainte-Foy, QC, Canada, G1K 7P4
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13
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Nielsen TT, Trottier NL, Stein HH, Bellaver C, Easter RA. The effect of litter size and day of lactation on amino acid uptake by the porcine mammary glands123. J Anim Sci 2002. [DOI: 10.1093/ansci/80.9.2402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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14
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Bernard L, Chauveau B, Rémond D. Effect of the methodology on peptide amino acid concentrations in blood and plasma of sheep. ARCHIV FUR TIERERNAHRUNG 2002; 54:281-96. [PMID: 11921851 DOI: 10.1080/17450390109381985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Different methodologies for the measurement of peptide amino acid (PAA) in blood and plasma were compared in sheep. Preparation of blood and plasma samples consisted of a deproteinization, either chemical with sulfosalicylic acid (0.04 g for 1 ml of sample) or physical by ultrafiltration (10,000-MW cut-off filters), with or without a subsequent ultrafiltration through a 3,000-MW cut-off filter. Peptide concentrations were determined by quantification of amino acid concentrations before and after acid hydrolysis of samples. Free amino acid concentrations were similar by all the method used (about 2.5 and 2.7 mM, for blood and plasma respectively). Peptide concentrations were higher with chemical deproteinization (10.6 and 4.2 mM, for blood and plasma respectively) than with physical deproteinization (5.7 and 3.3 mM, for blood and plasma respectively). When the deproteinized samples were further treated to remove material of molecular weight above than 3 kDa, peptide concentrations were significantly reduced, which indicates inefficiencies in the ability of the deproteinizing procedures in removing all the proteinaceous materials. Concentration of small PAA (< 3 kDa) in blood was about 1.5-fold that in plasma, mainly due to peptide Gly and Glu derived from the hydrolysis of the erythrocyte glutathione. The choice of a methodology for quantifying circulating peptides is discussed.
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Affiliation(s)
- L Bernard
- Unité de Recherche sur les Herbivores, Institut National de la Recherche Agronomique de Clermont-Ferrand, 63122 St Genès-Champanelle, France.
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15
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Thivierge MC, Petitclerc D, Bernier JF, Couture Y, Lapierre H. Variations in mammary metabolism during the natural filling of the udder with milk over a 12-h period between two milkings. J Dairy Sci 2002; 85:1839-54. [PMID: 12201535 DOI: 10.3168/jds.s0022-0302(02)74258-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Two groups of four Holstein cows, one in their second and the other in their third or fourth lactation, were used to study temporal variations of mammary metabolism over a 12-h period between two milkings. Blood samples were collected every 30 min from an artery and a mammary vein during a 12-h interval between two milkings. Isoleucine, leucine, lysine, methionine, and phenylalanine mammary net fluxes varied or tended to change over time after milking with a similar pattern between whole blood and plasma. For these amino acids, whole blood and plasma net fluxes reached their maximum over the first 8 h after milking. Simultaneously, respiratory quotients decreased linearly and varied from 2.31 to 2.01 during the first 8 h of the period, suggesting active mammary lipogenesis. From 8 to 12 h after milking, mammary amino acid net fluxes decreased, while mammary oxygen uptake tended to increase with a concomitant decrease in the respiratory quotient reaching 1.84 to 1.40. These findings suggest that, beginning 8 h after milking, mammary uptake of amino acids starts to decrease and catabolic processes appear promoted; this phenomenon could help to explain the increase in milk production reported in the literature with increased milking frequency.
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Affiliation(s)
- M C Thivierge
- Département des sciences animales, Université Laval, Sainte-Foy, QC, Canada
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16
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Hanigan MD, Crompton LA, Metcalf JA, France J. Modelling mammary metabolism in the dairy cow to predict milk constituent yield, with emphasis on amino acid metabolism and milk protein production: model construction. J Theor Biol 2001; 213:223-39. [PMID: 11894993 DOI: 10.1006/jtbi.2001.2417] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous efforts to simulate mammary metabolism have focused on energy, mostly considering amino acids (AA) in aggregate. The main objective of this work was to build a model of mammary metabolism, based on data from arterio-venous difference studies, which considered AA in sufficient detail to predict yields of milk solids. The model contains 19 state variables and considers the removal of 37 metabolites from blood, including 22 AA. It is driven by blood flow and arterial concentrations, and outputs include milk protein, milk lactose, and three classes of milk fat (by chain length). The model was parameterized using a balance version of it and the mean observations from four arterio-venous difference experiments, with a limited number of assumptions, and evaluated against these experiments. In assembling the balance model, milk protein output was not predicted satisfactorily, as some essential AA were not present in quantities great enough to support the rates of milk protein synthesis observed experimentally. Tryptophan showed the greatest deficit, followed by tyrosine plus phenylalanine, methionine, and histidine. In addition, significant quantities of pyruvate were needed to synthesize serine, glycine, and alanine. The supply of alpha-ketoglutarate plus glutamate to synthesize proline and glutamine was provided in part by catabolism of arginine; the remainder was derived from catabolism of other AA and energetic substrates.
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Affiliation(s)
- M D Hanigan
- Purina Mills Inc, St Louis, MO 63166-6812, USA
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17
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Bach A, Huntington GB, Calsamiglia S, Stern MD. Nitrogen metabolism of early lactation cows fed diets with two different levels of protein and different amino acid profiles. J Dairy Sci 2000; 83:2585-95. [PMID: 11104279 DOI: 10.3168/jds.s0022-0302(00)75152-6] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Four multiparous Holstein cows (569+/-122 kg) surgically prepared with indwelling catheters in the mesenteric, portal, and hepatic veins and carotid artery were allocated in a 4 x 4 Latin square to determine the effects of dietary crude protein (CP) level and amino acid (AA) profile on N metabolism during early lactation (from 25 to 65 d in milk). Cows received their diets in two equal meals and were milked twice daily. The dietary treatments were: 18% CP with a high (18H) or a low (18L) quality AA profile, and 15% CP with a high (15H) or a low (15L) quality AA profile. The four diets were similar in net energy for lactation (1.75 NEL Mcal/kg) and contained the same amount of RUP (34% of CP). The quality of the AA profile pertained only to the essential AA (EAA), and was assessed by comparison with the EAA profile of casein and considered the potential contribution of EAA from ruminal bacteria. The 18H and 15H diets were supplemented with 50 and 25 g/d of ruminally protected Met, respectively. After 10 d on treatment, a blood flow marker (p-amino-hippurate) was infused into a mesenteric vein, and arterial, portal, hepatic, and mammary blood samples were obtained at 3, 6, and 12 h after feeding. Dry matter intake was similar across treatments (23.4+/-0.5 kg/d). Amino acid oxidation, and consequent urea production, in the liver were numerically greater with the 18% CP rations, and, as a result, arterial urea concentrations were greatest (P < 0.01) with these rations. The amount of total AA extracted by the mammary gland tended to be greater with the H than with the L diets (21.4 vs. 18.2 mmol/ h, respectively). Milk yield tended to be greater (P = 0.16) with the 18H and 15H diets (47.7 and 46.3 kg/d, respectively) compared with the 18L and 15L diets (45.9 and 44.6 kg/d, respectively). Also, milk CP and casein contents were greatest (P = 0.09) with the H diets compared with the L diets. Milk and plasma urea N were greatest (P < 0.01) with the 18% CP diets. The efficiency of N utilization for milk protein synthesis was greatest (P < 0.09) with the 15% CP diets. It is concluded that milk protein production during early lactation is less susceptible to variations in dietary CP contents than variations in the AA profile of the dietary protein.
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Affiliation(s)
- A Bach
- Department of Animal Science, University of Minnesota, St. Paul 55108, USA
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Mackle TR, Dwyer DA, Ingvartsen KL, Chouinard PY, Ross DA, Bauman DE. Evaluation of whole blood and plasma in the interorgan supply of free amino acids for the mammary gland of lactating dairy cows. J Dairy Sci 2000; 83:1300-9. [PMID: 10877395 DOI: 10.3168/jds.s0022-0302(00)74996-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We investigated the contribution of plasma and red blood cells to amino acid (AA) supply for milk protein synthesis during a combination of treatments that included abomasal infusion of casein and AA and utilization of a hyperinsulinemic-euglycemic clamp. Treatments resulted in substantial differences in circulating concentrations of AA, mammary uptake of AA, and rates of milk protein synthesis. Arterial concentrations of all AA in plasma were highly correlated with that of whole blood. Concentrations of AA in red blood cells were either higher (Asn+Asp, Gly, His, Leu, Met, Orn, Ser, Tau, Thr, and Tyr), lower (Ala, Arg, Cit, Cys, Ile, and Val), or similar (Gln+Glu, Phe, and Pro) to that of plasma. Arteriovenous difference measurements demonstrated that interorgan transfer of AA to the mammary gland was primarily by plasma. There was little involvement of red blood cells except for small quantities of Leu, Met, and Thr to the mammary gland; this contribution was greatest for Met and accounted for 14% of the total mammary uptake. Countercurrent transport of Gln + Glu, Asn + Asp, and Pro was also evident where these AA were extracted from plasma, but were released into red blood cells as blood passed through the mammary gland. This net influx of Gln+Glu, Asn+Asp, and Pro into red blood cells was equivalent to 26, 17, and 30% of their mammary uptake from plasma. Overall, the interorgan transport of free AA for the mammary gland was predominantly by plasma, and red blood cells were limited to minor contributions in mammary uptake for a few AA. Furthermore, arteriovenous differences of essential AA across the mammary gland were highly correlated between plasma and whole blood.
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Affiliation(s)
- T R Mackle
- Department of Animal Science, Cornell University, Ithaca, NY 14853-4801, USA
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Mackle TR, Dwyer DA, Ingvartsen KL, Chouinard PY, Ross DA, Bauman DE. Effects of insulin and postruminal supply of protein on use of amino acids by the mammary gland for milk protein synthesis. J Dairy Sci 2000; 83:93-105. [PMID: 10659969 DOI: 10.3168/jds.s0022-0302(00)74860-0] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We examined the relationships between amino acid supply, net utilization of amino acid by the mammary gland, and milk protein yield, in investigations that utilized a hyperinsulinemic-euglycemic clamp. A two-way crossed factorial design was employed. There were two 12-d periods involving abomasal infusions of either water or a mixture of casein (500 g/d) plus branched-chain amino acids (88 g/d), with a hyperinsulinemic-euglycemic clamp during the last 4 d of each period. During the clamp, insulin was infused at 1.0 microg x kg BW(-1) x h(-1) to increase circulating levels fourfold, and euglycemia was maintained by infusion of glucose. The insulin clamp treatments increased milk protein yield by 15 and 25% during abomasal infusion of water or casein plus branched-chain amino acids, respectively. Circulating concentrations of essential amino acids were reduced (33%) during insulin clamp treatments, especially branched-chain amino acids (41%). Arteriovenous difference of essential amino acids across the mammary gland was linearly related to their arterial concentrations. However, milk protein yield was not related to either arterial concentration or arteriovenous difference, for any of the essential amino acids. During insulin clamp treatments, the mammary gland was able to support the increased milk protein yields by increasing extraction efficiency of essential amino acids, mammary blood flow, and glucose uptake. Furthermore, a positive mammary balance of total amino nitrogen and carbon was maintained for all treatments. These adaptations demonstrate the unique ability of the mammary gland to adjust local conditions to allow for an adequate nutrient supply.
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Affiliation(s)
- T R Mackle
- Department of Animal Science, Cornell University, Ithaca, NY 14853-4801, USA
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Bequette BJ, Backwell FR, Kyle CE, Calder AG, Buchan V, Crompton LA, France J, MaCrae JC. Vascular sources of phenylalanine, tyrosine, lysine, and methionine for casein synthesis in lactating goats. J Dairy Sci 1999; 82:362-77. [PMID: 10068958 DOI: 10.3168/jds.s0022-0302(99)75243-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The contribution to casein biosynthesis of peptides derived from blood was examined in late lactation goats (254 to 295 d in milk). Ratios of mammary uptake of free amino acids (AA) in blood to output of AA in milk protein and ratios of the enrichments of Phe, Tyr, Met, and Lys at isotopic plateau in secreted milk casein to the free AA in arterial and mammary vein blood were monitored during the last 5 h of a 30-h continuous i.v. infusion of [1-13C]Phe, [2H4]Tyr, [5-13CH3]Met, and [2-15N]Lys on two occasions: before (control) and on d 6 of an i.v. infusion of Phe (6 g/d). During the control, uptakes of free Phe and Met were less than their output in milk. This result was comparable with the labeling kinetic results, suggesting that vascular peptides contributed 5 to 11% of Phe and 8 to 18% of Met. Free Tyr and Lys uptakes during the control were sufficient for milk output; however, the labeling kinetics indicated that 13 to 25% of the Tyr and 4 to 13% of the Lys were derived from peptides. Infusion of Phe increased the uptake of free AA but reduced the contribution of peptides toward Phe (0 to 3%) and Tyr (8 to 14%) supply for casein synthesis. Whole body hydroxylation of Phe to Tyr increased from 10 to 18% with the infusion of Phe; within the mammary gland, this conversion was lower (3 to 5%). Results suggest that the mammary utilization of peptides containing Phe and Tyr appears to depend on the supply of free AA in blood.
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Affiliation(s)
- B J Bequette
- Rowett Research Institute, Bucksburn, Aberdeen, Scotland
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Johnson HA, Calvert CC, Baldwin RL. Designing a radioisotope experiment using a dynamic, mechanistic model of protein turnover. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1998; 445:345-59. [PMID: 9781400 DOI: 10.1007/978-1-4899-1959-5_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- H A Johnson
- Animal Sciences Department, University of California, Davis 95616, USA
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Quinn PJ, Boldyrev AA, Formazuyk VE. Carnosine: its properties, functions and potential therapeutic applications. Mol Aspects Med 1998; 13:379-444. [PMID: 9765790 DOI: 10.1016/0098-2997(92)90006-l] [Citation(s) in RCA: 213] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Carnosine and related dipeptides such as anserine are naturally-occurring histidine-containing compounds. They are found in several tissues most notably in muscle where they represent an appreciable fraction of the total water-soluble nitrogen-containing compounds. The biological role of these dipeptides are conjectural but they are believed to act as cytosolic buffering agents. Numerous studies have demonstrated, both at the tissue and organelle level, that they possess strong and specific antioxidant properties. Carnosine and related dipeptides have been shown to prevent peroxidation of model membrane systems leading to the suggestion that they represent water-soluble counterparts to lipid-soluble antioxidants such as alpha-tocopherol in protecting cell membranes from oxidative damage. Other roles ascribed to these dipeptides include actions as neurotransmitters, modulation of enzymic activities and chelation of heavy metals. Many claims have been made in respect of therapeutic actions of carnosine and histidine-containing dipeptides. These include antihypertensive effects, actions as immunomodulating agents, wound healing and antineoplastic effects. Many of these claims have not been convincingly documented nor subject to rigorous clinical evaluation. Nevertheless, there are examples where studies have shown considerable promise. One is the treatment of senile cataract in dogs and another is in acceleration of healing of surface wounds and burns to the skin. It is clear from this review that many of the effects of these histidine-containing dipeptides, especially in regard to claims for their therapeutic effects, need to be subjected to critical experimental and clinical examination. Several applications do, however, show clear evidence of being useful therapeutic agents.
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Affiliation(s)
- P J Quinn
- Biochemistry Department, King's College London, U.K
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23
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Maas JA, France J, Dijkstra J, Bannink A, McBride BW. Application of a mechanistic model to study competitive inhibition of amino acid uptake by the lactating bovine mammary gland. J Dairy Sci 1998; 81:1724-34. [PMID: 9684180 DOI: 10.3168/jds.s0022-0302(98)75740-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A mathematical model is used to describe uptake by a countertransport system and subsequent flow of three amino acids (AA), Phe, Val, and Met, from arterial blood to milk protein in the mammary gland of a lactating cow. The model suggests that total uptake of all AA is higher than net uptake and that a large proportion of the incoming AA is released from the cell directly back to blood. The model is used to predict which of the three AA is limiting the rate of milk protein synthesis and the response to increased arterial concentration of the first-limiting AA. Simulations are performed to predict possible outcomes of several experimental protocols to AA infusion, which might be used to test in vivo the responsiveness of the bovine mammary gland to an altered arterial concentration of AA. Of the three AA considered, arterial Met concentration appears to be first-limiting. The infusion profile that gives the greatest response in milk protein synthesis rate alters the arterial profile of AA such that it is identical to that of proteins originating in the mammary gland. Model construction can be simplified by acknowledging normal biological constraints.
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Affiliation(s)
- J A Maas
- Department of Animal and Poultry Science, University of Guelph, ON, Canada
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Xu S, Harrison JH, Chalupa W, Sniffen C, Julien W, Sato H, Fujieda T, Watanabe K, Ueda T, Suzuki H. The effect of ruminal bypass lysine and methionine on milk yield and composition of lactating cows. J Dairy Sci 1998; 81:1062-77. [PMID: 9594395 DOI: 10.3168/jds.s0022-0302(98)75668-1] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Fifty-six multiparous Holstein cows were assigned at 3 wk prepartum to rations based on grass silage with 1) corn distillers grains to provide 86 and 90% of estimated required metabolizable Lys and Met, respectively; 2) a blend of blood meal, fish meal, and meat and bone meal as amino acid (AA) sources to provide 112 and 103% of required metabolizable Lys and Met, respectively; 3) ruminally protected Lys and Met added as a top-dressing to ration 1 to provide 27 g/d of Lys and 8 g/d of Met as available AA at the duodenum postpartum; and 4) ruminally protected AA for 8 wk postpartum as a top-dressing to ration 1 to provide 40 g/d of Lys and 13 g/d of Met as available AA at the duodenum. Cows fed rations 3 and 4 were offered 13.5 g/d of duodenally available Lys and 4 g/d of duodenally available Met for 3 wk prepartum. The total length of the study was 43 wk. Cows fed ration 4 consumed 3 to 4 kg more dry matter than did cows fed the other three rations, and milk yield and the percentage of milk protein and fat were significantly increased during the first 8 wk of lactation. In early lactation, cows fed ration 3 had a greater milk fat percentage but similar dry matter intake, protein percentage, and yield of 4% fat-corrected milk compared with cows fed ration 2. The concentrations of blood serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, triglyceride, and nonesterified fatty acids were lower for cows fed ration 4 during the first 8 wk of lactation than they were for cows fed the other three rations. The mammary arteriovenous difference of whole blood AA indicated that Met along with His and Arg may be the most limiting AA for milk yield.
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Affiliation(s)
- S Xu
- Department of Animal Science, Washington State University, Puyallup 98371, USA
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26
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Hanigan MD, France J, Wray-Cahen D, Beever DE, Lobley GE, Reutzel L, Smith NE. Alternative models for analyses of liver and mammary transorgan metabolite extraction data. Br J Nutr 1998; 79:63-78. [PMID: 9505804 DOI: 10.1079/bjn19980010] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Alternative models for analyses of liver and mammary transorgan data were formulated and fitted to liver and mammary data sets respectively. The models considered metabolite inputs to and effluxes from an extracellular pool. In general, fits were greatly improved over previous efforts using other models (Miller et al. 1991a; Hanigan et al. 1992; Wray-Cahen et al. 1997). Errors of prediction were generally less than 15% for liver and less than 20% for mammary glands. With the possible exception of glutamine for the udder, all metabolites exhibited linear responses to extracellular concentrations within the observed ranges of inputs. However, prediction biases were evident for beta-hydroxybutyrate, acetate, and propionate by liver and for arginine, histidine, citrulline and glycerol by mammary tissue. These biases were hypothesized to be caused by the existence of additional regulatory complexity. With the exception of histidine, parameter estimates for essential amino acid removal by liver were 2-3-fold lower than for mammary gland. Infusion of an amino acid mixture into the mesenteric vein did not alter parameter estimates for removal of amino acids by the liver. Treatment of cows with bovine somatotropin resulted in changes in mammary parameter estimates for aspartate, glutamate, leucine, phenylalanine, glucose, and glycerol.
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Affiliation(s)
- M D Hanigan
- Purina Mills, Inc., St Louis, MO 63144, USA.
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Lykos T, Varga GA. Varying degradation rates of total nonstructural carbohydrates: effects on nutrient uptake and utilization by the mammary gland in high producing Holstein cows. J Dairy Sci 1997; 80:3356-67. [PMID: 9436118 DOI: 10.3168/jds.s0022-0302(97)76311-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Six ruminally cannulated Holstein cows at 56 to 77 d of lactation were fed three total mixed rations that varied in ruminal degradation rates of total nonstructural carbohydrates (6.04, 6.98, and 7.94%/h). The design was a 3 x 6 Latin square with 21-d experimental periods. Cows were catheterized in the jugular vein and in one of the caudal superficial epigastric veins. Increases in the ruminal degradation rate of total nonstructural carbohydrates 1) elevated mammary blood flow and blood concentrations of nonessential amino acids; 2) decreased arteriovenous differences and extraction rates of essential and most nonessential amino acids, but not of Gln and Glu (analyzed together) and glucose; 3) increased mammary uptake of Gln, Glu, and glucose; milk protein concentrations of Glu, Pro, and Asp; and total nonessential amino acids; and 4) did not alter uptake to output ratios of amino acids in the mammary gland, however, of the nonessential amino acids, only the uptake to output ratios for Glu and Gln increased (19%). Glucose and amino acid arteriovenous differences were not strongly correlated with their arterial concentrations. Increases in the ruminal degradation rate of total nonstructural carbohydrates increased intestinal digestibilities of total nonstructural carbohydrates and protein and increased uptake of energy substrates by the mammary gland, resulting in a 13% improvement in the utilization of nonessential amino acids for milk protein synthesis and in higher milk production and milk protein yields.
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Affiliation(s)
- T Lykos
- Department of Dairy and Animal Science, Pennsylvania State University, University Park 16803, USA
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Bequette BJ, Backwell FR, Calder AG, Metcalf JA, Beever DE, MacRae JC, Lobley GE. Application of a U-13C-labeled amino acid tracer in lactating dairy goats for simultaneous measurements of the flux of amino acids in plasma and the partition of amino acids to the mammary gland. J Dairy Sci 1997; 80:2842-53. [PMID: 9406077 DOI: 10.3168/jds.s0022-0302(97)76249-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A preliminary study was conducted using lactating British Saanen goats (n = 5) at 109 to 213 d in milk that yielded 1.67 to 3.68 kg of milk/d to examine the application of a U-13C-labeled amino acid (AA) mixture obtained from hydrolyzed algal proteins as a tracer for measuring plasma flux (n = 5) and partition to the mammary gland (n = 3; arteriovenous difference) of 13 AA simultaneously. Except for Ile and Ser, there was incomplete (6 to 54%) equilibration of the tracer with AA from packed blood cells (> 90% erythrocytes) during the 6-h infusions. This result agreed with the large ratio of packed cells to gradients for plasma AA concentration that was also observed. However, net mass and isotope removals by the mammary gland were predominantly from plasma, indicating that the erythrocytes did not participate in kinetic exchanges. Plasma AA fluxes (millimoles per kilogram of metabolizable protein intake per kilogram of body weight 0.75) differed among goats that consumed different protein sources; however, overall rates were lowest for Met (5 to 14) and His (8 to 17) and highest for Leu (48 to 70) and Ala (53 to 88). On average, 25% of plasma flux was partitioned to the mammary gland. Less than 20% of His, Ser, Phe, and Ala were directed to the mammary gland; 20 to 30% of Arg, Thr, Tyr, and Leu were directed to the mammary gland; and 30 to 40% of Pro, Ile, Lys, and Val were directed to the mammary gland. The unidirectional AA flux in the mammary gland (AA apparently available for protein syntheses, oxidation, and metabolite formation) did not match the pattern that is required for casein synthesis, suggesting differences in the metabolic requirements of AA for nonmilk protein synthesis.
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Affiliation(s)
- B J Bequette
- Rowett Research Institute, Bucksburn, Aberdeen, Scotland
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Bequette BJ, Backwell FR. Amino acid supply and metabolism by the ruminant mammary gland. Proc Nutr Soc 1997; 56:593-605. [PMID: 9264110 DOI: 10.1079/pns19970060] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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30
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Trottier NL. Nutritional control of amino acid supply to the mammary gland during lactation in the pig. Proc Nutr Soc 1997; 56:581-91. [PMID: 9264109 DOI: 10.1079/pns19970059] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The paucity of data relating to lactation physiology of the sow has frustrated researchers in estimating nutrient needs for production and mammary maintenance functions. The nutritional control of amino acid supply for milk synthesis is influenced by factors that have yet to be measured, such as blood flow and amino acid contribution from the body protein pool. The interaction or role of hormones such as insulin, glucagon or prolactin in amino acid dynamics and inter-organ exchange during lactation in the sow, are not well understood. The discrepancy existing between milk and mammary amino acid uptake profiles relative to lysine may be indicative of mammary metabolism and possibly maintenance requirements for specific amino acids. Hence, amino acid metabolism in the mammary gland, regardless of arterial blood substrate supply, may play an important role in a factorial approach to determining requirements. Mammary amino acid uptake ratios rather than milk amino acid ratios should provide a better tool to estimate amino acid requirements relative to lysine. Although lysine has typically been limiting in maize-soyabean-meal-based diets fed to lactating sows, current production trends are bringing a new dimension to the formulation of lactating-sow diets. Other amino acids may become limiting if dietary crystalline lysine is added without concern for the whole essential amino acid profile. Formulations based on an ideal amino acid profile for the lactating sow will, therefore, become critical.
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Affiliation(s)
- N L Trottier
- Michigan State University, Department of Animal Science, East Lansing 48824, USA
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Bequette BJ, Backwell FR, MacRae JC, Lobley GE, Crompton LA, Metcalf JA, Sutton JD. Effect of intravenous amino acid infusion on leucine oxidation across the mammary gland of the lactating goat. J Dairy Sci 1996; 79:2217-24. [PMID: 9029360 DOI: 10.3168/jds.s0022-0302(96)76598-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Changes in the kinetics of leucine in the mammary gland were examined in four lactating goats (25, 38, 45, and 135 DIM) that were given an i.v. infusion of a mixture of 18 AA, not including leucine, to alter the availability of leucine to the gland relative to other AA. Arteriovenous monitoring of [1-13C]leucine kinetics across one-half of the mammary gland was conducted on the last day (d 6 or 7) of the saline (control) and the AA infusion periods. Although blood flow to the mammary gland and the arterial concentration of most AA other than leucine were increased by the AA infusion, milk and protein yields did not change. For goats in early lactation (n = 3), arterial leucine concentrations fell considerably during AA infusion; however, the arteriovenous difference of leucine was maintained, resulting in uncommonly low leucine concentrations in venous plasma (8 microM). Whole body leucine flux (protein synthesis plus oxidation) was unaffected by AA infusion, but, because whole body leucine oxidation was reduced, whole body utilization of leucine for protein synthesis increased. The AA infusion reduced mammary oxidation of leucine to approximately one-third of control values. These results suggest that leucine oxidation can be reduced considerably without affecting milk protein output; thus, leucine oxidation may not be an irrevocable consequence of mammary metabolism. If catabolism of other AA either by the gland or in the whole body can be reduced, then the efficiency of milk yield can be improved.
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Affiliation(s)
- B J Bequette
- Rowet Research Institute, Bucksburn, Aberdeer, Scotland
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32
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Bequette BJ, Metcalf JA, Wray-Cahen D, Backwell FR, GFtton JD, Lomax MA, Macrae JC, Lobley GE. Leucine and protein metabolism in the lactating dairy cow mammary gland: responses to supplemental dietary crude protein intake. J DAIRY RES 1996; 63:209-22. [PMID: 8861345 DOI: 10.1017/s002202990003171x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Mammary gland protein metabolism, determined by an arteriovenous difference technique, was monitored in four Holstein-Friesian dairy cows in response to supplemental dietary protein (provided as rumen-protected soyabean meal) during late lactation (weeks 24-30). Each cow was offered two isoenergetic diets composed of grass silage (170 g crude protein/kg dry matter) plus either a low (108 g/kg) or medium (151 g/kg) crude protein concentrate in a single crossover design involving two 21 d periods. On day 21, arteriovenous measurements across the mammary gland were made during a 13 h continuous i.v. infusion of [1-(13)C]leucine and with frequent (2 hourly) milk sampling during the final 6 h. Although total milk yield was slightly increased (+1 kg/d) by protein supplementation, milk protein yield was not significantly affected. Whole body protein flux (protein synthesis plus oxidation) was not significantly affected by supplementation. Total mammary gland protein synthesis (milk plus non-milk protein) was also not affected by supplementation but on both diets gland synthesis was always greater (by 20-59 percent) than milk protein output. The fractional oxidation rate of leucine by the mammary gland was significantly increased by protein supplementation (0-047 v. 0-136). Although the enrichment of leucine in secreted milk protein continued to increase, the final value (at 13 h) was 0-94 of the arterial plasma free leucine plateau value (not significantly different), suggesting almost exclusive use of plasma free leucine for milk protein synthesis. Based on current feeding schemes for dairy cattle, a fixed proportion (0-65 0-75) of the additional protein intake (+490 g/d) should have been partitioned into milk protein. Instead, leucine oxidation by the mammary gland was increased. Whether oxidation of other amino acids was also enhanced is unknown but if amino acid oxidation and the 'additional' non-milk protein synthesis occurring in the gland are not crucial to milk synthesis, then by reducing such activities improvements in the efficiency of converting absorbed amino acid into milk protein can be achieved.
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Affiliation(s)
- B J Bequette
- Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB, UK
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33
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Metcalf JA, Wray-Cahen D, Chettle EE, Sutton JD, Beever DE, Crompton LA, MacRae JC, Bequette BJ, Backwell FR. The effect of dietary crude protein as protected soybean meal on mammary metabolism in the lactating dairy cow. J Dairy Sci 1996; 79:603-11. [PMID: 8744225 DOI: 10.3168/jds.s0022-0302(96)76405-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Metabolism in the mammary gland was related to changes in milk output in response to changes in dietary protein intake. Three diets of grass silage and concentrate were fed to four lactating dairy cows equipped with intravascular catheters across the mammary gland. Concentrates differed in the inclusion of protected soybean meal and provided 11.3, 15.4, and 20.1% CP, respectively. Blood samples were taken to assess the effect of protein percentage on the nutrient fluxes across the gland and their relationship to milk production. Milk production, milk protein yield, and milk protein concentration were all increased as CP intake increased, although these responses were not linear. Concentrations of urea in milk reflected those in plasma and increased as dietary protein intake increased. Uptake of glucose and BHBA by the mammary gland tended to increase as milk production increased. Arterial supply of essential AA increased as the dietary protein increased. Supply and uptake of nonessential AA were unchanged by dietary treatment, and uptake was insufficient to account for output of nonessential AA residues in milk protein. The supply of essential AA was not limiting for milk protein synthesis, and some alternative mechanism must have existed for the control of milk protein yield.
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Affiliation(s)
- J A Metcalf
- Agricultural and Food Research Council Institute of Grassland and Environmental Research, Maidenhead, Berkshire, England
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Guinard J, Rulquin H. Effect of graded levels of duodenal infusions of casein on mammary uptake in lactating cows. 2. Individual amino acids. J Dairy Sci 1994; 77:3304-15. [PMID: 7814706 DOI: 10.3168/jds.s0022-0302(94)77271-4] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The experiment examined patterns of mammary uptake of individual AA when graded amounts of calcium caseinate (0, 177, 362, and 762 g/d) were infused duodenally into four lactating cows. Six blood samples were collected over 12 h from the subcutaneous abdominal vein and the carotid. Mammary blood flow was measured by an ultrasonic flow probe implanted around the external pudic artery. Infusions of casein linearly increased the arterial concentrations of all essential AA and several nonessential AA (Pro, Tyr, Orn, and Cit) and increased, or tended to increase, linearly the mammary arteriovenous differences of all AA except Glu and Ala. Absorption ability of the mammary gland was not reduced in vivo. Relationships between mammary arteriovenous differences and arterial concentrations were positive and linear in every cow for all AA except Asn, Ser, Gly, and Ala. Some essential AA (Lys, Arg, and branched-chain AA) were therefore taken up in excess of their output into milk proteins, but others (His, Thr, Met, and Phe) were almost exclusively extracted by the udder in a direct ratio to their output. As infusions of casein increase, Phe becomes probably the most critical AA for milk synthesis.
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Affiliation(s)
- J Guinard
- Station de Recherches sur la Vache Laitière, Institut National de la Recherche Agronomique, St-Gilles, France
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Baldwin RL, Emery RS, McNamara JP. Metabolic relationships in the supply of nutrients for milk protein synthesis: integrative modeling. J Dairy Sci 1994; 77:2821-36. [PMID: 7814748 DOI: 10.3168/jds.s0022-0302(94)77222-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The objective of research under the NC-185 regional project is to identify the critical chemical transformations in the rumen, digestive tract, gastrointestinal and splanchnic tissues, and adipose and mammary tissues that define patterns of nutrient utilization in lactating dairy cows. This objective includes research on differences in fermentation, digestion, absorption, and tissue utilization of nutrients in sufficiently different situations to permit estimation of parameters defining various nutrient interconversions. The regional project is utilizing dynamic, mechanistic models of metabolism as tools for integrative analyses of experimental data generated by the group. During the early phases of the project emphasized herein, primary emphasis was on development of models of adipose tissue, mammary gland, liver, rumen, and whole animal metabolism. Serious inadequacies exist in the detail and scope of knowledge of rates of chemical transformations across the wide range of milk yields and nutrient intakes found in production situations. Current knowledge, as described in the various equations and parameters in the models, is presented and discussed. Some characteristics of the current models are illustrated, and methods to utilize the models to identify important experiments are discussed. More cooperative efforts are necessary, including experimental designs that focus on quantification of relationships between input and output, physiological mechanisms that alter patterns of nutrient utilization in lactating dairy cows, and yield estimates of the parameters describing the pre- and postabsorptive uses of feed nutrients.
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Affiliation(s)
- R L Baldwin
- Department of Animal Science, University of California, Davis 95616-8521
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Reynolds CK, Harmon DL, Cecava MJ. Absorption and delivery of nutrients for milk protein synthesis by portal-drained viscera. J Dairy Sci 1994; 77:2787-808. [PMID: 7814746 DOI: 10.3168/jds.s0022-0302(94)77220-9] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The predictability of diet effects on milk composition is limited by the lack of understanding of the metabolic transformations that absorbed nutrients undergo within the portal-drained viscera and liver of high yielding dairy cows. The mass of splanchnic tissues increases dramatically in early lactation, but little is known about the regulation of gut growth and adaptation in early lactation, and further research may provide strategies for optimizing gut adaptation. Glucose is critical for milk synthesis, but portal-drained visceral tissues normally use rather than absorb glucose on a net basis. Dietary starch of low ruminal digestibility increases postruminal starch digestion and decreases net use of glucose by portal-drained viscera slightly, but increases in glucose absorption by portal-drained viscera never account fully for increases in starch disappearance from the small intestine and occur at the expense of VFA absorption. For cows in positive energy balance, greater glucose availability increases tissue energy balance and glucose oxidation, but has little effect on milk or milk protein yield. Similarly, chronic increases in propionate absorption have little effect on milk or milk protein yield. In contrast, casein infusion into the small intestine consistently increases milk and milk protein yield, but the mechanisms responsible remain unclear. There are few data describing the absorption and metabolism of AA by splanchnic tissues of lactating dairy cows, but, as for glucose and VFA, utilization of many AA by portal-drained viscera is substantial. In addition, the contribution of peptides to AA absorption and transport is uncertain and must be clarified. Therefore, measurements of nutrient disappearance from the lumen of the gut cannot be equated with nutrient appearance in the portal vein. Data describing metabolism of nutrients by portal-drained viscera and liver of high yielding dairy cows are needed to improve feeding standards.
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Affiliation(s)
- C K Reynolds
- USDA, Agricultural Research Service, Ruminant Nutrition Laboratory, Beltsville, MD 20705
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37
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Abstract
This paper reviews the current state of knowledge about the postabsorptive utilization of AA. Data on the duodenal entry of AA and the projected output of these same AA as milk protein demonstrate significant losses. Within the essential AA, these losses range from 70% for Thr to 40% for Met and Lys. For Val, almost half of the loss is due to its use for nonsecretory purposes by the mammary gland; values decrease to 0% for other AA. The liver is the other major organ, apart from the portal-drained viscera, that is responsible for significant AA disposal. Interactions of Met metabolism with other methyl sources and gluconeogenic precursors that can alter the Met requirement also are discussed. Data on the transhepatic and transsplanchnic AA balance in lactating cows, and the coordinated use of these balances with duodenal flow and mammary balance, are needed. Further research also is needed into the functionality of use of AA for purposes other than milk protein synthesis to determine whether excess catabolism of AA occurs; assuming it does, more efforts are needed to identify regulation of AA disposal in the crucial tissues.
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Affiliation(s)
- L E Armentano
- Department of Dairy Science, University of Wisconsin, Madison 53706
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Bequette BJ, Backwell FR, Dhanoa MS, Walker A, Calder AG, Wray-Cahen D, Metcalf JA, Sutton JD, Beever DE, Lobley GE. Kinetics of blood free and milk casein-amino acid labelling in the dairy goat at two stages of lactation. Br J Nutr 1994; 72:211-20. [PMID: 7947641 DOI: 10.1079/bjn19940025] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The kinetics of blood free amino acids (AA) transfer into milk casein were compared in goats (n 4) at 61 (SE 5) d (Expt 1; post-peak, 4.51 (SE 0.26) kg milk/d) and at 180 (SE 6) d (Expt 2; late, 2.36 (SE 0.16) kg milk/d) of lactation during non-primed, continuous (Expt 1, 12 h; Expt 2, 16 h) intravenous infusions of mixtures of L-[1-13C]leucine and L-[1-13C]phenylalanine with either L-[1-13C]valine (Expt 1) or L-[5-13C]methionine (Expt 2). The 13C enrichments of blood free and casein-bound AA were fitted to a single exponential model to estimate isotopic plateaux and the fractional rate constant for milk casein labelling. Milk protein output and its contribution to whole-body flux was higher in Expt 1 (post-peak) than in Expt 2 (late lactation), but the kinetics of 13C labelling of the casein-bound AA were similar for all AA tracers in both experiments. At both stages of lactation the delay (6-8 h) between the attainment of isotopic plateau for the blood free AA and the corresponding attainment of plateau for the casein-bound AA indicated that the blood free pool was not the immediate precursor pool for milk casein biosynthesis. Plateau enrichments of casein-bound AA were generally higher than those for the corresponding blood free AA in both experiments. These results indicate that the relative contributions of different AA sources to the immediate precursor pool for milk casein biosynthesis are similar at different stages of lactation despite major changes in the partitioning of whole-body flux towards milk protein output. Non-milk protein fluxes were also similar in post-peak and late lactation.
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Wu Z, Huber J. Relationship between dietary fat supplementation and milk protein concentration in lactating cows: A review. ACTA ACUST UNITED AC 1994. [DOI: 10.1016/0301-6226(94)90180-5] [Citation(s) in RCA: 126] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Knight C, France J, Beever D. Nutrient metabolism and utilization in the mammary gland. ACTA ACUST UNITED AC 1994. [DOI: 10.1016/0301-6226(94)90164-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Cant JP, DePeters EJ, Baldwin RL. Mammary amino acid utilization in dairy cows fed fat and its relationship to milk protein depression. J Dairy Sci 1993; 76:762-74. [PMID: 8463488 DOI: 10.3168/jds.s0022-0302(93)77400-7] [Citation(s) in RCA: 125] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Changes in mammary AA utilization associated with dietary fat-induced milk protein depression were assessed in cows with disturbed AA status. Four first lactation cows fitted with rumen cannulas were assigned to a factorial arrangement of treatments: two diets and two casein infusion sites within a 4 x 4 Latin square design. Diets were formulated with yellow grease at 0 or 4% of DM. An 8% sodium caseinate solution was infused continuously at 5.04 kg/d into the rumen or abomasum during the last 5 d of each 21-d period. Arterial AA concentrations were reduced by dietary fat treatment and increased by abomasal sodium caseinate infusion. Mammary arteriovenous differences of essential AA tended to increase with both abomasal casein infusion and dietary fat treatments. With ruminal casein infusion treatments, yellow grease supplementation increased the percentage of extraction of blood essential AA into mammary tissue. Mammary blood flow rate dropped 7% on high fat treatments, preventing an increase in uptakes of critical AA to accompany the improved efficiency of milk synthesis, which was evident from a significantly reduced ratio of mammary blood flow to milk volume, resulting in depressed milk protein content.
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Affiliation(s)
- J P Cant
- Department of Animal Science, University of California, Davis 95616
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42
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Krogmeier D, Mao I, Bergen W. Single Gene Control of Glutathione Concentration in Blood and Its Association with Yield Traits in Lactating Holstein Cows. J Dairy Sci 1993. [DOI: 10.3168/jds.s0022-0302(93)77385-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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43
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DePeters EJ, Cant JP. Nutritional factors influencing the nitrogen composition of bovine milk: a review. J Dairy Sci 1992; 75:2043-70. [PMID: 1401362 DOI: 10.3168/jds.s0022-0302(92)77964-8] [Citation(s) in RCA: 243] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- E J DePeters
- Department of Animal Science, University of California, Davis 95616-8521
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Hanigan MD, Calvert CC, DePeters EJ, Reis BL, Baldwin RL. Kinetics of amino acid extraction by lactating mammary glands in control and sometribove-treated Holstein cows. J Dairy Sci 1992; 75:161-73. [PMID: 1541729 DOI: 10.3168/jds.s0022-0302(92)77750-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Studies of mammary arteriovenous difference were conducted on multiparous lactating Holstein cows (n = 21) on d 35, 70, 105, and 126 of lactation to examine kinetic relationships between arterial concentration and mammary gland extraction of AA. Additionally, these cows were paired by previous lactational performance and assigned to bST-treated or control groups to examine the effect of bST treatment on AA concentration and extraction by lactating mammary glands. Treated cows were injected daily with 40 mg of recombinant bST from d 71 through 126 of lactation. Arterial concentrations of Asp, Ser, Asn, Gly, beta-aminoisobutyrate, and Met were increased. Concentrations of Val, Ile, Leu, Phe, Orn, and Lys were decreased in bST-treated cows compared with controls. Increased extractions of Asp and Met by mammary glands in treated versus control cows were correlated positively with treatment-induced changes in arterial concentrations of these AA. However, increased mammary extractions of Arg, cystathionine, Leu, and Lys by bST-treated compared with control cows were not correlated with bST-induced changes in arterial concentrations of these AA. Extractions of Asn, His, Thr, Arg, Tyr, Met, cystathionine, cystine, Ile, Phe, Orn, Glu, Gly, Tau, Cit, Leu, and Val were correlated linearly with arterial concentrations (r2 greater than .15) of each AA. Extractions of Asp, Glu, Ser, Asn, Gly, Gln, Tau, His, Cit, Thr, Pro, Tyr, Val, cystine, Ile, Leu, Trp, Orn, and Lys also were correlated with arteriovenous differences of Met.
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Affiliation(s)
- M D Hanigan
- Department of Animal Science, University of California, Davis 95616
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