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The effect of variation in dietary protein or mineral supply on calcium and phosphorus metabolism in lactating ewes

Published online by Cambridge University Press:  09 March 2007

A. A. J. Rajaratne ,
D. Scott ,
W. Buchan  and
A. Duncan
A. A. J. Rajaratne
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
D. Scott
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
W. Buchan
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
A. Duncan
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
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Abstract

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Two experiments are described in which changes in both nitrogen and mineral balance were monitored in ewes during lactation. In Expt 1, two groups (n 6) of ewes were fed on diets that were either high (15 g crade protein (N × 6.25; CP)/MJ metabolizable energy (ME)) or low (10 g CP/MJ ME) in protein content, and concurrent N and mineral balance studies were made at intervals during lactation with 45Ca and 32P being used to monitor faecal endogenous calcium and phosphorus losses. Ewes fed on the high-protein diet maintained a positive N balance during early lactation, whereas those fed on the low-protein diet were in negative N balance. Both groups, however, showed the same degree of negative Ca and P balance, with the amounts lost being directly related to milk yield. This indicates that loss of mineral from the skeleton at this time is not secondary to a loss of bone matrix due to a shortfall in dietary protein supply. In Expt 2, two groups of ewes (n 4) were fed on diets in late pregnancy that were either just adequate or generous in Ca and P supply relative to requirement (TCORN, 1990). After parturition both groups were fed on a diet which was formulated to meet their estimated Ca and P requirements for lactation. As in the previous experiment both groups were in negative Ca and P balance in early lactation and variation in dietary Ca and P supply during pregnancy had no effect on the extent of this loss. Alternative explanations for the cause of this loss of mineral from the skeleton are discussed.

Keywords

Calcium metabolismPhosphorus metabolismLactationSheep
Type
Lactation in Ruminants
Information
British Journal of Nutrition , Volume 64 , Issue 1 , July 1990 , pp. 147 - 160
Copyright
Copyright © The Nutrition Society 1990

References

Agricultural Research Council (1980). The Nutrient Requirements of Ruminant Livestock. Farnham Royal: Commonwealth Agricultural Bureaux.Google Scholar
Allgrove, J., Adami, S., Manning, R. M., Chayen, J. & O'Riordan, J. L. H. (1985). Cytochemical bioassay of parathyroid hormone in maternal and cord blood. Archives of Diseases in Childhood 60, 110–115.CrossRefGoogle ScholarPubMed
Black, D., Duncan, A. & Robins, S. P. (1988). Quantitative analysis of pyridinium cross-links of collagen in urine using ion-paired reverse-phase high-performance liquid chromatography. Analytical Biochemistry 169, 197–203.CrossRefGoogle Scholar
Braithwaite, G. D. (1978). The effect of dietary calcium intake of ewes in pregnancy on their Ca and phosphorus metabolism in lactation. British Journal of Nutrition 39, 213–218.CrossRefGoogle ScholarPubMed
Braithwaite, G. D. (1983 a). Calcium and phosphorus requirements of the ewe during pregnancy and lactation. 1. Calcium. British Journal of Nutrition 50, 711–722.CrossRefGoogle ScholarPubMed
Braithwaite, G. D. (1983 b). Calcium and phosphorus requirements of the ewe during pregnancy and lactation. 2. Phosphorus. British Journal of Nutrition 50, 723–736.CrossRefGoogle ScholarPubMed
Braithwaite, G. D., Glascock, R. F. & Riazuddin, S. H. (1969). Calcium metabolism in lactating ewes. British Journal of Nutrition 23, 827–833.CrossRefGoogle ScholarPubMed
Brommage, R. & De Luca, H. F. (1985). Regulation of bone mineral loss during lactation. American Journal of Physiology 248, E182–E187.Google ScholarPubMed
Chrisp, J. S., Sykes, A. R. & Grace, N. D. (1989). Kinetic aspects of calcium metabolism in lactating sheep offered herbages with different Ca concentrations and the effect of protein supplementation. British Journal of Nutrition 61, 45–58.CrossRefGoogle ScholarPubMed
Davidson, J., Mathieson, J. & Boyne, A. W. (1970). The use of automation in determining nitrogen in the Kjehldahl method with final calculation by computer. Analyst 95, 181–183.CrossRefGoogle Scholar
Field, A. C., Coop, R. L., Dingwall, R. A. & Munro, C. S. (1982). The phosphorus requirements for growth and maintenance of sheep. Journal of Agricultural Science, Cambridge 99, 311–317.CrossRefGoogle Scholar
Field, A. C., Kamphues, J. & Woolliams, J. A. (1983). The effect of dietary intake of calcium and phosphorus on the absorption and excretion of phosphorus in chimaera-derived sheep. Journal of Agricultural Science, Cambridge 101, 597–692.CrossRefGoogle Scholar
Forbes, J. M. (1977). Interrelationships between physical and metabolic control of voluntary food intake in fattening, pregnant and lactating sheep: a model. Animal Production 24, 91–101.Google Scholar
Gitelman, H. J. (1967). An improved automated procedure for the determination of calcium in biological fluids. Analytical Biochemistry 18, 521–531.CrossRefGoogle Scholar
Gonzalez, J. S., Robinson, J. J., McHattie, I. & Fraser, C. (1982). The effect in ewes of source and level of dietary protein on milk yield, and the relationships between the intestinal supply of non-ammonia nitrogen and the production of milk protein. Animal Production 34, 31–40.Google Scholar
Lawes Agricultural Trust (1984). Genstat V.Mark 4.01 Rothampstead Experimental Station, Harpenden, Hertfordshire.Google Scholar
Moseley, J. M., Kubota, M., Diefenbach-Jagger, H., Wettenhall, R. E. H., Kemp, B. E., Suva, L. J., Rodda, C. P., Ebeling, P. J., Hudson, J. D., Zajac, J. D. & Martin, T. J. (1987). Parathyroid hormone-related protein purified from a human lung cancer cell line. Proceedings of the National Academy of Science. USA 84, 5048–5052.CrossRefGoogle Scholar
Ørskov, E. R., Hovell, F. D.De, B. & Mould, F. (1980). The use of the nylon bag technique for the evaluation of feedstuffs. Tropical Animal Production 5, 195–213.Google Scholar
Ramberg, C. F. Jr, Mayer, G. P., Kronfeld, D. S., Phang, J. M. & Berman, M. (1970). Calcium kinetics in cows during late pregnancy, parturition and early lactation. American Journal of Physiology 219, 1166–1177.CrossRefGoogle ScholarPubMed
Roach, A. G. (1965). Application of Technicon autoanalyzer equipment to the routine determination of calcium and phosphorus in animal feedstuffs. In Automation in Analytical Chemistry, Technicon Symposia, pp. 137–141 [Skeggs, L. T. J., editor]. New York: Mediad Incorporated.Google Scholar
Sykes, A. R. & Geenty, K. G. (1986). Calcium and phosphorus balances of lactating ewes at pasture. Journal of Agricultural Science, Cambridge 109, 357–364.Google Scholar
TCORN (1990). A reappraisal of the calcium and phosphorus requirements of sheep and cattle. Nutrition Abstracts and Reviews (In the Press).Google Scholar
Thiede, M. A. & Rodan, G. A. (1988). Expression of a Calcium-mobilizing parathyroid hormone-like peptide in lactating mammary tissue. Science 242, 278–280.CrossRefGoogle ScholarPubMed
Treacher, T. T. (1970). Apparatus and milking techniques used in lactation studies with sheep. Journal of Dairy Research 37, 289–295.CrossRefGoogle Scholar
Yarrington, J. T., Capen, C. C., Black, H. E. & Re, R. (1977). Effects of a low Ca prepartal diet on calcium homeostasis mechanisms in the cow. Morphological and Biochemical studies. Journal of Nutrition 107, 2244–2256.CrossRefGoogle Scholar
Young, D. S. (1966). An improved method for the automatic determination of serum inorganic phosphate. Journal of Clinical Pathology 19, 397–399.CrossRefGoogle ScholarPubMed