Hostname: page-component-77c89778f8-cnmwb Total loading time: 0 Render date: 2024-07-22T03:06:41.224Z Has data issue: false hasContentIssue false
  • English
  • Français

The relationship in the cow between milk-fat secretion and ruminal volatile fatty acids

Published online by Cambridge University Press:  09 March 2007

J. E. Storry  and
J. A. F. Rook
J. E. Storry
Affiliation:
National Institute for Research in Dairying, Shinfild, Reading
J. A. F. Rook
Affiliation:
National Institute for Research in Dairying, Shinfild, Reading
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 effect of reducing the hay and of increasing the proportions of concentrate and flaked maize in the diet of cows on the secretion of milk fat and its component fatty acids and on the proportions of volatile fatty acids in the rumen liquor has been studied. 2. The low-hay diet caused a fall in the milk fat content to about half of the values in the initial control period and the secretion of all the major fatty acids in the milk was reduced. The general pattern of change in the proportions of rumen VFA during the change to the low-hay diet was a decrease in acetic acid, an increase in propionic and n-valeric acids, relatively little change in n-butyric acid and also an increase in the concentration of lactic acid. Approximately 60% of the variation in milk fat content during the change of diet was associated with the increase in propionic acid. 3. In cows established on the low-hay diet there were marked variations in the relative proportions of acetic and propionic acids, but there was no related change in milk fat content. On return of the animals to the high-hay diet, recovery of the initial proportions of acetic, propionic and valeric acids occurred within about 4 days but the recovery in milk fat content was not complete until 2–3 weeks had elapsed. 4. Although the intraruminal infusion of acetic acid in cows on the low-hay diet caused increases and decreases respectively in the molar proportions of acetic and propionic acids in the rumen, an increase in milk fat content was observed amounting to only one-quarter of the loss associated with the transfer to the low-hay diet; therem was no characteristic pattern of increase in the yields of the individual fatty acids of milk fat. No consistent effects of intraruminal infusions of butyric acid, in cows on the low-hay diet, on the yield of milk fat or of the individual fatty acids were observed.

Type
Research Article
Information
British Journal of Nutrition , Volume 20 , Issue 2 , May 1966 , pp. 217 - 228
Copyright
Copyright © The Nutrition Society 1966

References

REFERENCES

Annison, E. F. (1954). Biochem. J. 58, 670.CrossRefGoogle Scholar
Balch, C. C., Balch, D. A., Bartlett, S., Cox, C. P. & Rowland, S. J. (1952). J. Dairy Res. 19, 39.CrossRefGoogle Scholar
Balch, C. C., Broster, W. H., Rook, J. A. F. & Tuck, V. J. (1965). J. Dairy Res. 32, 1.CrossRefGoogle Scholar
Balch, C. C. & Rowland, S. J. (1959). J. Dairy Res. 26, 162.CrossRefGoogle Scholar
Bath, I. H. & Rook, J. A. F. (1965). J. agric. Sci., Camb., 64, 67.CrossRefGoogle Scholar
Bergman, E. N., Reid, R. S., Murray, M. G., Brockway, J. M. & Whitelaw, F. G. (1965). Biochem. J. 97, 53.CrossRefGoogle Scholar
Blaxter, K. L. & Wainman, F. W. (1964). J. agric. Sci., Camb., 63, 113.CrossRefGoogle Scholar
British Standards Institution (1955). B.S. 696, Part I, p. 7.Google Scholar
Donefer, E., Lloyd, L. E. & Crampton, E. W. (1962). J. Anim. Sci. 21, 993.CrossRefGoogle Scholar
Elsden, S. R. & Gibson, Q. H. (1954). Biochem. J. 58, 154.CrossRefGoogle Scholar
Gray, F. V., Jones, G. B. & Pilgrim, A. F. (1960). Aust. J. agric. Res. 11, 383.CrossRefGoogle Scholar
Gray, F. V., Pilgrim, A. F., Rodda, H. J. & Weller, R. A. (1952). J. exp. Biol. 29, 57.CrossRefGoogle Scholar
Jorgensen, N. A. (1964). Diss. Abstr. 25, 2128.Google Scholar
Jorgensen, N. A., Schultz, L. H. & Barr, G. R. (1965). J. Dairy Sci. 48, 1031.CrossRefGoogle Scholar
King, R. L. & Hemken, R. W. (1962). J. Dairy Sci. 45, 1336CrossRefGoogle Scholar
Rook, J. A. F. & Balch, C. C. (1961). Br. J. Nutr. 15, 361.CrossRefGoogle Scholar
Rook, J. A. F., Balch, C. C., Campling, R. C. & Fisher, L. J. (1963). Br. J. Nutr. 17, 399.CrossRefGoogle Scholar
Rook, J. A. F. & Storry, J. E. (1964). Chemy Ind. p. 1778.Google Scholar
Sheppard, A. J., Forbes, R. M. & Johnson, B. C. (1959). Abstr. Pap. Am. chem. Soc. 135th Mtg, p. 11A.Google Scholar
Stanley, R. W., Morita, K. & Ueyama, E. (1964). J. Dairy Sci. 47, 258.CrossRefGoogle Scholar
Stoddard, G. E., Allen, N. N. & Peterson, W. H. (1949). J. Anim. Sci. 8, 630.Google Scholar
Storry, J. E. & Millard, D. (1965). J. Sci. Fd Agric. 16, 417.CrossRefGoogle Scholar
Storry, J. E. & Rook, J. A. F. (1965 a). Br. J. Nutr. 19, 101.CrossRefGoogle Scholar
Storry, J. E. & Rook, J. A. F. (1965 b). Biochem. J. 95, 473.Google Scholar
Tyznik, W. & Allen, N. N. (1951). J. Dairy Sci. 34, 493.Google Scholar