Hostname: page-component-77c89778f8-vsgnj Total loading time: 0 Render date: 2024-07-22T21:21:17.187Z Has data issue: false hasContentIssue false
  • English
  • Français

A new approach to the measurement of the quantitative effects of inherent and environmental factors on the composition of the milk of individual cows and of herds, with particular reference to lactose content

Published online by Cambridge University Press:  01 June 2009

J. P. Walsh ,
J. A. F. Rook  and
F. H. Dodd
J. P. Walsh
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading
J. A. F. Rook
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading
F. H. Dodd
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading
Get access Rights & Permissions [Opens in a new window]

Summary

(1) A tentative scheme is proposed for the quantitative estimation of the effects of various factors on one major milk constituent, lactose, from analyses of the milk of individual cows within herds. The potential lactose content in the milk of individual cows is predicted from the observed potassium-to-lactose ratio in the milk, and the difference between the predicted potential and the actual lactose content is partitioned into fractions that are attributed to effects due to age, inter-quarter difference and changes with stage of lactation. The scheme was applied to 2 commercial herds, one (herd A) producing milk of low and the other (herd B) milk of normal SNF content.

(2) Lactation mean values for fat, SNF and lactose contents of the milk of individual cows showed a wide range of the same order in each of the 2 herds. Of the mean difference in SNF percentage of 0·30 between the herds, 0·14, or 47%, was due to a difference in lactose content.

(3) The predicted potential milk lactose content of the cows in the 2 herds ranged from 5·04 to 5·66 (g/100 g milk water). Herd mean values were 5·394 for herd A and 5·244 for herd B.

(4) Herd mean values for the effect on the lactose content (g/100 g milk water) of age, of changes with stage of lactation and of inter-quarter difference were −0·127, −0·080, and 0·073 respectively in herd A, and −0·197, −0·058 and −0·078, respectively, in herd B.

(5) The relative importance of the various factors in accounting for differences between the herds in the lactose content of their bulk milk were: predicted potential lactose content 61%, effect of age 28%, effect of changes with stage of lactation 9% and effect of inter-quarter difference 2%.

(6) The errors attached to the estimation of potential milk lactose content and the effects of age, of changes with stage of lactation and of inter-quarter difference are discussed.

Type
Original Articles
Information
Journal of Dairy Research , Volume 35 , Issue 1 , February 1968 , pp. 91 - 105
Copyright
Copyright © Proprietors of Journal of Dairy Research 1968

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Alexander, W. H. & Leech, F. B. (1960). J. Dairy Res. 27, 19.CrossRefGoogle Scholar
Breed, R. S. (1929). Bull. N.Y. St. agric. Exp. Stn no. 568, 14.Google Scholar
BRITISH STANDARDS INSTITUTION (1951). B.S. 1741, p. 7.Google Scholar
BRITISH STANDARDS INSTITUTION (1955). B.S. 696, p. 7.Google Scholar
Brumby, P. J. (1961). Anim. Prod. 3, 277.Google Scholar
Burr, H. (1939). Thesis, Reading University.Google Scholar
Dawes, S. N. (1965). N.Z. Jl Sci. 8, 161.Google Scholar
Edwards, R. A. (1958). J. Dairy Res. 25, 9.Google Scholar
Foot, A. S. (1964). J. Soc. Dairy Technol. 17, 34.Google Scholar
Foot, A. S., Line, C. & Rowland, S. J. (1961). Rep. natn. Inst. Res. Dairy, p. 34.Google Scholar
Griffiths, T. W. & Featherstone, J. (1957). J. Dairy Res. 21, 201.CrossRefGoogle Scholar
Hinton, C. L. & Macara, T. (1927). Analyst, Lond. 52, 668.Google Scholar
Holland, M. G. (1960). N.Z. Dairy Export. 35, 49.Google Scholar
Mclean, J. W. (1951). Tech. Publ Canterbury agric. Coll. no. 7.Google Scholar
Meyer, H. (1964). Prakt. Tierarzt 45, 4–6, 50–54.Google Scholar
Munro, R. F. & Bailey, R. W. (1958). Milk Bd. Jl N.S.W. 9, no.12, 23.Google Scholar
Murphy, J. M. & Hanson, J. J. (1941). Cornell Vet. 31, 47.Google Scholar
O'donovan, J., Dodd, F. H. & Neave, F. K. (1960). J. Dairy Res. 27, 115.Google Scholar
Provan, A. L. (1956). Variations in the Composition of Milk from Individual Animals and Herds. Rep. Milk Marketing Board.Google Scholar
Robertson, A. & Rendel, J. M. (1954). J. agric. Sci., Gamb., 44, 184.Google Scholar
Rook, J. A. F. (1961). Dairy Sci. Abstr. 23, 351.Google Scholar
Rook, J. A. F. & Campling, R. C. (1965). J. Dairy Res. 32, 45.Google Scholar
Rook, J. A. F. & Wood, M. (1959). Nature, Lond. 184, 647.Google Scholar
Rowland, S. J., Neave, F. K., Dodd, F. H. & Oliver, J. (1959). 15th Int. Dairy Congr. London 1,121.Google Scholar
Van Koetsveld, E. E. (1965). Landbouwk. Tijdschr., Wageningen 77, 205.Google Scholar
Walsh, J. P. & Rook, J. A. F. (1964). Nature, Lond. 204, 353.Google Scholar
Wiener, J. P. (1960). J. Soc. Anim. Prod. 2, 117.Google Scholar