Hostname: page-component-8448b6f56d-jr42d Total loading time: 0 Render date: 2024-04-24T00:32:08.287Z Has data issue: false hasContentIssue false
  • English
  • Français

Mammary metabolism in lactating sows: arteriovenous differences of milk precursors and the mammary metabolism of [14C]glucose and [14C]acetate

Published online by Cambridge University Press:  09 March 2007

J. L. Linzell ,
T. B. Mepham ,
E. F. Annison  and
C. E. West
J. L. Linzell
Affiliation:
Institute of Animal Physiology, Babraham, Cambridge
T. B. Mepham
Affiliation:
Institute of Animal Physiology, Babraham, Cambridge
E. F. Annison
Affiliation:
Unilever Research Laboratory, Sharnbrook, Bedford
C. E. West
Affiliation:
Unilever Research Laboratory, Sharnbrook, Bedford
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

1. The following techniques, which have been applied successfully to goats, were used to study mammary metabolism in lactating sows:(I) measurements of mammary arteriovenous (A-V) differences in milk precursors in the conscious undisturbed animal (five sows); (2) continuous intravenous infusion of [U-14C]glucose with concomitant arterial and mammary venous blood sampling for measurement of mammary blood flow and specific radioactivity of glucose and CO, (one sow); (3) perfusion of the isolated gland in vitro (eight glands from four sows), with the inclusion of [U-14C]glucose (two glands) and [U-14C]acetate(two glands) in the substrate mixture.

2. Sow mammary tissue was similar to that goats in its milk yield, blood flow, and glucose uptake per unit weight of tissue. As in goats, mammary uptake of glucose was many times that of the rest of the body and the total mammary tissue was utilizing about half of the total glucose entering the circulation. Glucose was a major source of milk lactose and glycerol and of mammary CO2.

3. Of the plasma lipid components, only the triglyceride fraction was consistently and significantly removed by the gland. In contrast to the results obtained for the goat, both [U-14C[acetate and [U-14C]glucose carbon were used for milk fatty acid synthesis, and although the pattern of labelling of fatty acid from each precursor was similar, the formation of fatty acids from glucose was at least five times greater than that from acetate. Quantitative evaluation of the contribution of these precursors was not possible, but the RQ (1.09–1.63) suggest that in some instances it may have been considerable.

4. The substantial A-V differences of most plasma essential amino acids suggest that these are the sole precursors of the corresponding residues in the mammary synthesized protein. The low A-V differences for several non-essential amino acids suggest that these are synthe- sized in the gland; this suggestion is supported by the incorporation of glucose carbon into non-essential amino acid residues of casein observed in one experiment. However, in contrast to results with the goat, mammary absorption of serine was consistently large.

Type
Research Article
Information
British Journal of Nutrition , Volume 23 , Issue 2 , June 1969 , pp. 319 - 333
Copyright
Copyright © The Nutrition Society 1969

References

Annison, E. F. & Linzell, J. L. (1964). J. Physiol., Lond. 175, 372.CrossRefGoogle Scholar
Annison, E. F., Linzell, J. L., Fazakerley, S. & Nichols, B. W. (1967). Biochem. J. 102, 637.CrossRefGoogle Scholar
Annison, E. F., Linzell, J. L. & West, C. E. (1968).J. Physiol., Lond. 197, 445.CrossRefGoogle Scholar
Bickerstaffe, R. & Annison, E. F. (1968). Biochem. J. 108, 47P.Google Scholar
Graham, W. R., Kay, H. D. & McIntosh, R. A. (1936). Proc. R. Soc. B 120, 319.Google Scholar
Gutte, J. O., Kleiber, M., Raggi, F. R. & Black, A. L. (1961).Z. Tierphysiol. Tieremähr, Futtermittelk. 16, 171.CrossRefGoogle Scholar
Hardwick, D. C. (1965). Biochem. J. 95, 233.CrossRefGoogle Scholar
Hardwick, D. C. & Linzell, J. L. (1960). J. Physiol., Lond. 154, 547.CrossRefGoogle Scholar
Hardwick, D. C., Linzell, J. L. & Mepham, T. B. (1963). Biochem. J. 88, 213.CrossRefGoogle Scholar
Linzell, J. L. (1960). J. Physiol., Lond. 153, 492.CrossRefGoogle Scholar
Linzell, J. L. (1966 a). J. Dairy Sci. 49, 307.CrossRefGoogle Scholar
Linzell, J. L. (1966 b). Circulation Res. 18, 745.CrossRefGoogle Scholar
Linzell, J. L., Annison, E. F., Fazakerley, S. & Leng, R. A. (1967). Biochem. J. 104, 34.CrossRefGoogle Scholar
Linzell, J. L. & Mepham, T. B. (1968). Biochem. J. 107, 18P.Google Scholar
Linzell, J. L., Mepham, T. B., Annison, E. F. & West, C. E. (1967).Biochem. J. 103, 42P.Google Scholar
Mepham, T. B. & Linzell, J. L. (1966). Biochem. J. 101, 76.CrossRefGoogle Scholar
Mepham, T. B. & Linzell, J. L. (1967). Nature, Lond. 214, 507.CrossRefGoogle Scholar
Morgan, D. O. & Lecce, J. G. (1964). Res. vet. Sci. 4, 332.CrossRefGoogle Scholar
Rook, J. A. F. & Witter, R. C. (1968). Proc. Nutr. Soc. 27, 71.CrossRefGoogle Scholar
Salmon-Legagneur, E. (1967). Nutrition of the lactating sow. Proc. Symp. Nutrition of sows. P.I.D.A. Nottingham.Google Scholar
Seldinger, S. I. (1953). Acta radiol. 39, 368.CrossRefGoogle Scholar
Setchell, B. P. & Waites, G. M. H. (1964). J. Physiol., Lond. 171, 411.CrossRefGoogle Scholar
Shaw, J. C. & Petersen, W. E. (1939). Proc. Soc. exp. Biol. Med. 42, 520.CrossRefGoogle Scholar
Turner, C. W. (1952). The Mammary Gland. Vol. 1. The Anatomy of the Udder of Cattle and Domestic Animals. Columbia, Missouri: Lucas Bros.Google Scholar
West, C. E., Rowbotham, T. R. (1967). J. Chromat. 30, 62.CrossRefGoogle Scholar
Williamson, D. H., Mellanby, J. & Krebs, H. A. (1962). Biochem. J. 82, 90.CrossRefGoogle Scholar
Wünsche, J., Herrmann, U. & Bock, H.-D. (1967). Nährung 11, 331.CrossRefGoogle Scholar