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Utilization of nutrients by the dairy cow and optimal N:energy ratio in the diet

Published online by Cambridge University Press:  01 June 2009

R. Paquay
Affiliation:
Department of Animal Physiology, Faculty of Veterinary Medicine, Cureghem, 1070-Brussels, Belgium
J. M. Godeau
Affiliation:
Department of Animal Physiology, Faculty of Veterinary Medicine, Cureghem, 1070-Brussels, Belgium
R. De Baere
Affiliation:
Department of Animal Physiology, Faculty of Veterinary Medicine, Cureghem, 1070-Brussels, Belgium
A. Lousse
Affiliation:
Department of Animal Physiology, Faculty of Veterinary Medicine, Cureghem, 1070-Brussels, Belgium

Summary

The dietary and individual animal factors influencing the utilization of digestible nitrogen and of metabolizable energy for milk production were studied and change in the optimal nitrogen:energy ratio during lactation was investigated using 35 different experimental diets and the individual results obtained from 119 Friesian cows whose daily milk production varied from 4 to 30kg.

The amount of N secreted in the milk and the daily milk production depended above all on the metabolizable energy intake and on the stage of lactation. They were related to the dietary N: energy ratio.

The percentages of digestible N and of metabolizable energy utilized for milk production were also related to the dietary digestible N: metabolizable energy ratio of the diet.

The optimal digestible N:metabolizable energy ratio ranged from about 2·2g/MJ during the first 3 months of lactation to about 1·7g/MJ in the sixth and seventh months and 1·3g/MJ from the tenth month. When expressed in g N intake per MJ energy intake, this optimal ratio ranged from 1·6 after calving to 1·1 at the end of lactation.

Type
Research Article
Copyright
Copyright © Proprietors of Journal of Dairy Research 1973

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References

REFERENCES

Acord, C. R., Mitchell, G. E. Jr & Little, C. O. (1968). Journal of Dairy Science 51, 1249.Google Scholar
Agricultural Research Council (1965). The nutrient requirements of farm livestock. 2. Ruminants. London: H.M.S.O.Google Scholar
Allison, M. J. (1969). Journal of Animal Science 29, 797.CrossRefGoogle Scholar
Armstrong, D. G. (1968). Proceedings of the Nutrition Society 27, 57.Google Scholar
Association of Official Agricultural Chemists (1965). Official methods of analysis, 10th edn.Washington, D.C.: A.O.A.C.Google Scholar
Bines, J. A. (1971). Proceedings of the Nutrition Society 30, 116.Google Scholar
Blaxter, K. L. (1962). The energy metabolism of ruminants. London: Hutchinson.Google Scholar
Blaxter, K. L. (1964). In Mammalian Protein Metabolism, 2, 173. (Eds Munro, H. N. and Allison, J. B..) New York: Academic Press.CrossRefGoogle Scholar
Bolduan, G., Voigt, J. & Piatkowski, B. (1972). Archiv für Tierernährung 22, 389.Google Scholar
Broster, W. H. (1972). Dairy Science Abstracts 34, 265.Google Scholar
Broster, W. H., Broster, V. J. & Smith, T. (1969). Journal of Agricultural Science 72, 229.CrossRefGoogle Scholar
Cloete, J. G. (1966). South African Journal of Agricultural Science 9, 379.Google Scholar
Coombe, J. B. & Christian, K. R. (1969). Journal of Agricultural Science 72, 261.Google Scholar
Decaen, C., Calomiti, S. & Poutous, M. (1970). Annales de Zootechnie 19, 205.CrossRefGoogle Scholar
De Baere, R., Paquay, R. & Lousse, A. (1966). Annales de Médecine Vétérinaire 110, 81.Google Scholar
Elliott, R. C. & Topps, J. H. (1963 a). British Journal of Nutrition 17, 549.Google Scholar
Elliott, R. C. & Topps, J. H. (1963 b). Animal Production 5, 269.Google Scholar
Fonnesbeck, P. V., Harris, L. E. & Cook, C. W. (1970). Journal of Animal Science 30, 283.Google Scholar
Forbes, J. M. (1970). British Veterinary Journal 126, 1.CrossRefGoogle Scholar
Gardner, R. W. (1969). Journal of Dairy Science 52, 1973.Google Scholar
Gordon, F. J. & Forbes, T. J. (1970). Journal of Dairy Research 37, 481.Google Scholar
Gordon, F. J. & Forbes, T. J. (1971). Journal of Dairy Research 38, 381.CrossRefGoogle Scholar
Holter, J. B., Kim, C. W. & Colovos, N. F. (1972). Journal of Dairy Science 55, 460.CrossRefGoogle Scholar
Hoogendoorn, A. L. & Grieve, C. M. (1970). Journal of Dairy Science 53, 1028.CrossRefGoogle Scholar
Huber, J. T. & Thomas, J. W. (1971). Journal of Dairy Science 54, 224.CrossRefGoogle Scholar
Jacquot, R., Le Bars, H., Leroy, A. M. & Simonnet, H. (1964). Nutrition animale, 3. Paris: J. B. Baillière et Fils.Google Scholar
Joslyn, M. A. (1950). Methods in Food Analysis. New York: Academic Press.Google Scholar
McLaren, G. A. (1964). Journal of Animal Science 23, 577.CrossRefGoogle Scholar
Ørskov, E. R. & Oltjen, R. R. (1967). Journal of Nutrition 93, 222.Google Scholar
Paquay, R., De Baere, R. & Lousse, A. (1972 a). Journal of Agricultural Science 78, 141.CrossRefGoogle Scholar
Paquay, R., De Baere, R. & Lousse, A. (1972 b). Journal of Agricultural Science 79, 323.Google Scholar
Paquay, R., Godeau, J. M., De Baere, R. & Lousse, A. (1973). Journal of Dairy Research 40, 93.Google Scholar
Rook, J. A. F., Line, C. & Rowland, S. J. (1960). Journal of Dairy Research 27, 427.CrossRefGoogle Scholar
Satapathy, N. (1969). Indian Veterinary Journal 46, 886.Google Scholar
Snedecor, G. W. & Cochran, W. G. (1967). Statistical Methods, 6th edn.Ames, Iowa: Iowa State University Press.Google Scholar
Thomas, J. W. (1971). Journal of Dairy Science 54, 1629.Google Scholar
Tyrrell, H. F., Moe, P. W. & Flatt, W. P. (1970). In Energy metabolism of farm animals: 5th symposium, Vitznau, p. 69. (Eds Schürch, A. and Wenk, C..) Zurich: Juris Druck & Verlag. (Publications of the European Association for Animal Production, no. 13.)Google Scholar
Vaillant, R. (1967). In Production du lait, p. 113. (Ed. Ferrando, R..) Paris: Flammarion.Google Scholar
Van Niekerk, B. D. H., Smith, D. W. W. Q. & Oosthuysen, D. (1967). Proceedings of the South African Society of Animal Production 6, 108.Google Scholar
Waldo, D. R. (1968). Journal of Dairy Science 51, 265.Google Scholar
Walker, D. M. & Norton, B. W. (1971). Journal of Agricultural Science 77, 363.Google Scholar
Wheelock, J. V. & Dodd, F. H. (1969). Journal of Dairy Research 36, 479.Google Scholar
Wiktorsson, H. (1971). Swedish Journal of Agricultural Research 1, 83.Google Scholar
Wilson, L. L., Varela-Alvarez, H., Hess, C. E. & Rugh, M. C. (1971). Journal of Animal Science 33, 686.Google Scholar
Yousef, I. M., Huber, J. T. & Emery, R. S. (1970). Journal of Dairy Science 53, 734.CrossRefGoogle Scholar