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Effects of exogenous bovine somatotropin on milk yield and pasture intake in dairy cows of low or high genetic merit

Published online by Cambridge University Press:  02 September 2010

A. Michel ,
S. N. McCutcheon ,
D. D. S. Mackenzie ,
R. M. Tait  and
B. W. Wickham
A. Michel
Affiliation:
Department of Animal Science, Massey University, Palmerston North, New Zealand
S. N. McCutcheon
Affiliation:
Department of Animal Science, Massey University, Palmerston North, New Zealand
D. D. S. Mackenzie
Affiliation:
Department of Animal Science, Massey University, Palmerston North, New Zealand
R. M. Tait
Affiliation:
Department of Animal Science, University of British Columbia, Vancouver, Canada
B. W. Wickham
Affiliation:
Livestock Improvement Corporation, New Zealand Dairy Board, Hamilton, New Zealand
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Abstract

The effect of recombinantly derived bovine somatotropin (bST) treatment on milk production and pasture intake was examined in 16 New Zealand Friesian cows from low or high genetic merit (breeding index) selection lines. Recombinantly derived bST was administered by 2-weekly injection of a controlled release formulation for a period of 4 weeks (weeks 16 to 19 of lactation) at a dose rate equivalent to 50 mg/day. During this period the animals were housed for 18 days with food intake being measured over the last 8 days. Treatment with bST resulted in significantly higher yields of milk, fat and protein compared with the controls. Cows from the low breeding index (LBI) line were more responsive to exogenous bST than cows of the high breeding index (HBI) line in both milk and fat yield. Milk composition was not affected by bST treatment. There was a significant increase of proportionately 0·108 in intake of freshly cut pasture between bST-treated and untreated animals during days 16 to 23 of treatment. Thus, no significant difference in calculated energy balance was observed between the bSTtreated and untreated cows. This study indicates that the genetic background of cows may be an important determinant of their response to bST treatment and that such treatment rapidly alters voluntary intake in pasture-fed cows.

Keywords

dairy cowsfood intakemilk productionsomatotropin
Type
Research Article
Information
Animal Production , Volume 51 , Issue 2 , October 1990 , pp. 229 - 234
Copyright
Copyright © British Society of Animal Science 1990

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References

REFERENCES

Bauman, D. E., Eppard, P. J., Degeeter, M. J. and Lanza, G. M. 1985a. Responses of high-producing dairy cows to long-term treatment with pituitary somatotropin and recombinant somatotropin. Journal of Dairy Science 68: 1352–1362.Google Scholar
Bauman, D. E., McCutcheon, S. N., Steinhour, W. D., Eppard, P. J. and Sechen, S. J. 1985b. Sources of variation and prospects for improvement of productive efficiency in the dairy cow: a review. Journal of Animal Science 60: 583–592.Google Scholar
Bines, J. A., Hart, I. C. and Morant, S. V. 1980. Endocrine control of energy metabolism in the cow: the effect on milk yield and levels of some blood constituents of injecting growth hormone and growth hormone fragments. British Journal of Nutrition 43: 179–188.Google Scholar
Davey, A. W. F., Grainger, C., MacKenzie, D. D. S., Flux, D. S., Wilson, G. F., Brookes, I. M. and Holmes, C. W. 1983. Nutritional and physiological studies of differences between Friesian cows of high and low genetic merit. Proceedings of the New Zealand Society of Animal Production 43: 67–70.Google Scholar
Eppard, P. J., Bauman, D. E. and McCutcheon, S. N. 1985. Effect of dose of bovine growth hormone on lactation of dairy cows. Journal of Dairy Science 68: 1109–1115.Google Scholar
Gilmour, A. R. 1985. REG — a generalized linear models program. Miscellaneous Bulletin, Division of Agricultural Services, Department of Agriculture, New South Wales, No. 1.Google Scholar
Holmes, C. W. and Wilson, G. F. 1984. Milk Production from Pasture. Butterworths, Wellington.Google Scholar
Johnsson, I. D. and Hart, I. C. 1986. Manipulation of milk yield with growth hormone. In Recent Advances in Animal Nutrition — 1986 (ed. Haresign, W. and Cole, D. J. A.), pp. 105–123. Butterworths, London.CrossRefGoogle Scholar
Leitch, H. W., Burnside, E. B., MacLeod, G. K., McBride, B. W., Kennedy, B. W., Wilton, J. W. and Burton, J. H. 1987. Genetic and phenotypic effects of administration of recombinant bovine somatotropin to Holstein cows. Journal of Dairy Science 70: Suppl. 1, p. 128 (Abstr.).Google Scholar
McBride, B. W., Burton, J. L. and Burton, J. H. 1988. The influence of bovine growth hormone (somatotropin) on animals and their products. Research and Development in Agriculture 5: 1–21.Google Scholar
Nytes, A. J., Combs, D. K. and Shook, G. E. 1988. Efficacy of recombinant bovine somatotropin injected at three dosage levels in lactating dairy cows of different genetic potentials. Journal of Dairy Science 71: Suppl. 1, p. 123 (Abstr.).Google Scholar
Peel, C. J., Fronk, T. J., Bauman, D. E. and Gorewit, R. C. 1983. Effect of exogenous growth hormone in early and late lactation on lactational performance of dairy cows. Journal of Dairy Science 66: 776–782.Google Scholar
Peel, C. J., Sandles, L. D., Quelch, K. J. and Herington, A. C. 1985. The effects of long-term administration of bovine growth hormone on the lactational performance of identical-twin dairy cows. Animal Production 41: 135–142.Google Scholar
Tyrrell, H. F. and Reid, J. T. 1965. Prediction of the energy value of cow's milk. Journal of Dairy Science 48: 1215–1223.Google Scholar