Hostname: page-component-77c89778f8-9q27g Total loading time: 0 Render date: 2024-07-16T13:07:50.388Z Has data issue: false hasContentIssue false

Field investigations into hypomagnesaemia in dairy cattle, with particular reference to changes in the concentration of blood constituents during the early grazing period

Published online by Cambridge University Press:  27 March 2009

S. Bartlett
Affiliation:
National Institute for Research in Dairying, University of Reading
B. B. Brown
Affiliation:
National Institute for Research in Dairying, University of Reading
A. S. Foot
Affiliation:
National Institute for Research in Dairying, University of Reading
M. J. Head
Affiliation:
National Institute for Research in Dairying, University of Reading
C. Line
Affiliation:
National Institute for Research in Dairying, University of Reading
J. A. F. Rook
Affiliation:
National Institute for Research in Dairying, University of Reading
S. J. Rowland
Affiliation:
National Institute for Research in Dairying, University of Reading
G. Zundel
Affiliation:
National Institute for Research in Dairying, University of Reading

Extract

1. In five experiments, groups of milking cows were changed abruptly from winter-stall feeding to graze a number of different swards, and changes in the concentration of blood-serum magnesium and of other blood constituents have been studied.

2. Wide variations in the severity of hypomagnesaemia in individual cattle were found in all experimental groups, due possibly to such factors as individual variations in the intake of herbage, the requirement and body reserves of magnesium and the capacity to absorb magnesium from the gut.

3. The degree of hypomagnesaemia observed was independent of the level of milk production, but was generally less severe in Friesian than in Shorthorn and Guernsey cattle. The onset of hypomagnesaemia was delayed for a few days in cattle with a high serum-magnesium concentration at the commencement of grazing.

4. In two out of three experiments in which the effect of fertilizer treatment was studied, the incidence and severity of hypomagnesaemia was increased by the application to the sward of heavy dressings of nitrogenous fertilizer. In the third experiment, severe hypomagnesaemia occurred on a plot which had received no nitrogen fertilizer, due, it is thought, to a restricted intake of herbage magnesium, since the sward was extremely sparse. The feeding of supplements of flaked maize, crushed barley, crushed dredge corn, molassed sugar-beet pulp or a concentrate mixture balanced for milk production, to grazing cattle did not reduce the incidence of hypomagnesaemia.

5. The cutting of grass and feeding it in the stall did not prevent the development of hypomagnesaemia.

6. Blood pH and the concentrations of bloodserum calcium, sodium, potassium and blood glucose in cattle were unaffected by a change from winter feed to spring grazing, but a marked change in blood-serum non-protein and urea nitrogen and blood ammonia nitrogen, but not in any other nitrogenous constituents of the serum, was observed. The concentrations of serum non-protein and urea nitrogen and blood ammonia nitrogen were highest in groups of cattle grazing swards which had received a heavy dressing of nitrogen fertilizer and had a high nitrogen content.

7. In the two experiments in which the severity of hypomagnesaemia was increased by the application of nitrogenous fertilizer, there was a close group association between high concentrations of blood serum non-protein and urea nitrogen and blood ammonia and low concentrations of blood-serum magnesium. High levels of serum urea and blood ammonia during grazing are thought to reflect a high ammonia production in the gut, which may be responsible for the disturbance in magnesium metabolism which produces hypomagnesaemia.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1957

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

Allcroft, W. M. (1947). Brit. Vet. J. 103, 2, 30.Google Scholar
Allcroft, W. M. & Green, H. H. (1934). Biochem. J. 28, 2220.Google Scholar
Balch, C. C., Head, M. J., Line, C., Rook, J. A. F. & Rowland, S. J. (1956). Proc. Nutr. Soc. 15, x.Google Scholar
Barry, J. M. & Rowland, S. J. (1953 a). Biochem. J. 53, 213.CrossRefGoogle Scholar
Barry, J. M. & Rowland, S. J. (1953 b). Biochem. J. 54, 575.Google Scholar
Bartlett, S., Brown, B. B., Foot, A. S., Rowland, S. J., Allcroft, R. & Parr, W. H. (1954). Brit. Vet. J. 110, 3.CrossRefGoogle Scholar
Blakemore, F. & Stewart, J. (19321933). 3rd Rep. Director Inst. Anim. Path. Univ. Camb. p. 159.Google Scholar
Blaxter, K. L. & McGill, R. F. (1956). Vet. Rev. Annotat. 2, 35.Google Scholar
Blaxter, K. L., Rook, J. A. F. & MacDonald, A. M. (1954). J. Comp. Path. 64, 157.Google Scholar
Brouwer, F. (1952). Brit. Vet. J. 108, 123.Google Scholar
Brown, J. (1945). J. Biol. Chem. 158, 601.Google Scholar
Conway, E. J. (1939). Microdiffusion Analysis and Volumetric Error. London: Crosby, Lockwood and Son Ltd.Google Scholar
Davidson, J. (1952). Analyst, 77, 263.CrossRefGoogle Scholar
Dinning, J. S., Briggs, H. M., Gallup, W. D., Orr, H. W. & Butler, R. (1948). Amer. J. Physiol. 153, 41.Google Scholar
Dryerre, H. (1932). Vet. Rec. 12, 1163.Google Scholar
Edwards, H. T., Richards, T. K. & Dill, D. B. (1931). Amer. J. Physiol. 98, 352.CrossRefGoogle Scholar
Folin, O. & Wu, H. (1919). J. Biol. Chem. 38, 81.Google Scholar
Godden, W. (1935). Tech. Gommun. Bur. Anim. Nutr. no. 9.Google Scholar
Hawk, P. B., Oser, B. L. & Summerson, W. H. (1947). Practical Physiological Chemistry. London: J. and A. Churchill Ltd.Google Scholar
Head, M. J. & Rook, J. A. F. (1955). Nature, Lond., 176, 262.Google Scholar
Head, M. J. & Rook, J. A. F. (1957). Proc. Nutr. Soc. 16, 25.Google Scholar
King, J. O. L. (1954). B.V.A. Publ. no. 24, p. 61.Google Scholar
Latteur, J. P. (1953). Rev. Agric., Brux., 6, 899.Google Scholar
Nelson, N. (1944). J. Biol. Chem. 153, 375.CrossRefGoogle Scholar
Parr, W. H. & Allcroft, R. (1953). Proc. Nutr. Soc. 12, vii.Google Scholar
Peters, J. & Van Slyke, D. D. (1932). Quantitative Clinical Chemistry, vol. 2. London: Baillière, Tindall and Cox.Google Scholar
Seekles, L. (1955). European Ass. for Anim. Prod., 5th Study meeting.Google Scholar
Seekles, L. & Sjollema, B. (1932). Arch. wiss. prakt. Tierheilk. 65, 331.Google Scholar
Sjollema, B. (1930). Vet. Rec. 10, 425.Google Scholar
Sjollema, B. (1932). Tijdschr. Diergeneesk. 59, 57, 329.Google Scholar
Sjollema, B. & Seekles, L. (1929). Tijdschr. Diergeneesk. 56, 979.Google Scholar
Sjollema, B. & Seekles, L. (1933). Arch. wiss. prakt. Tierheilk. 66, 60.Google Scholar
Stewart, A. B. & Holmes, W. (1953). J. Sci. Fd Agric. 4, 401.CrossRefGoogle Scholar
Swan, J. B. & Jamieson, W. D. (1956). N.Z. J. Sci. Tech. A, 38, 137.Google Scholar
Thomas, J. W. & Okamoto, M. (1953). J. Dairy Sci. 36, 591.Google Scholar
White, J. B. (1953). B.V.A. Publ. no. 23, p. 35.Google Scholar