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The effect of roughage to concentrate ratio in the diet on protein and energy utilization by the non-pregnant ewe

Published online by Cambridge University Press:  27 March 2009

J. J. Robinson  and
T. J. Forbes
J. J. Robinson
Affiliation:
Agricultural Research Institute of Northern Ireland, Hillsborough, and The Queen's University of Belfast
T. J. Forbes
Affiliation:
Agricultural Research Institute of Northern Ireland, Hillsborough, and The Queen's University of Belfast
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Summary

Thirty-six Border Leicester x Scottish Blackface ewes were separated from their lambs after approximately 12 weeks lactation and brought indoors. They were allocated at random to nine dietary treatments comprising three dietary ratios of chopped roughage to concentrate, each offered at three levels of feeding. During the course of the experiment digestibility and nitrogen balance trials were carried out using three ewes from each dietary treatment.

The daily nitrogen intakes required for nitrogen equilibrium were calculated from the regressions of nitrogen intake on nitrogen retained for each of the three ratios. The intakes increased from 0·47 g/kg W0·75 on the diet containing the lowest proportion of roughage to 0·59 g/kg W0·75 on the diet containing the highest proportion of roughage. The corresponding digestible organic matter intakes did not differ significantly from the pooled value of 18·8 g/kg W0·75.

The daily digestible organic matter intakes required for the maintenance of live weight on the three ratios did not differ significantly from the pooled estimate of 26·9 g/kg W0·75 which is in close agreement with other published results. The nitrogen intakes required for the maintenance of live weight increased from 0·70 on the diet containing the lowest proportion of roughage to 0·84 g/kg W0·75/day on the diet containing the highest proportion of roughage.

The coefficients for live-weight change in the regression equations relating digestible organic matter to live weight and live-weight change for each ratio did not differ significantly from the pooled estimate of 2·0 g DOMI/g live-weight change.

The significance of the results are discussed in relation, to the nutritional status of the ewe and other research findings.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 74 , Issue 3 , June 1970 , pp. 415 - 421
Copyright
Copyright © Cambridge University Press 1970

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References

REFERENCES

Agricultural Research Council (1965). The Nutrient Requirements of Farm Livestock. No. 2, Ruminants. London: Agricultural Research Council.Google Scholar
Brody, S. (1945). Bioenergetics and Growth. New York: Reinhold Publishing Corp.Google Scholar
Blaxter, K. L. (1962). The Energy Metabolism of Ruminants. London: Hutchinson.Google Scholar
Blaxter, K. L. (1968). The effect of the dietary energy supply on growth. In Qrowth and Development of Mammals. Ed. Lodge, G. A. and Lamming, G. E.. London: Butterworths.Google Scholar
Broster, W. H., Tuck, Valerie J., Smith, T. & Johnson, V. W. (1969). Experiments on the nutrition of the dairy heifer. VII. Observations on the effect of the energy intake on the utilization of protein in growth and in lactation. J. agric. Sci., Camb. 72, 13–30.CrossRefGoogle Scholar
Doney, J. M. & Russel, A. J. F. (1968). Differences amongst breeds of sheep in food requirements for maintenance and live-weight change. J. agric. Sci., Camb. 71, 343–9.CrossRefGoogle Scholar
Elliott, R. C. & Topps, J. H. (1964). Studies on protein requirements of ruminants. III. Nitrogen balance trials on Blockhead Persian sheep given diets of different energy and protein content. Br. J. Nutr. 18, 245–52.CrossRefGoogle Scholar
Forbes, T. J. & Robinson, J. J. (1969). A study of the energy requirements of weaned lambs. Anim. Prod. 11, 389–97.Google Scholar
Graham, N. McC. (1964). Energy exchanges of pregnant and lactating ewes. Aust. J. agric. Res. 15, 127–41.Google Scholar
Langlands, J. P., Coebett, J. L., Mcdonald, I. & Pullae, J. D. (1963). Estimates of the energy required for maintenance by adult sheep. 1. Housed sheep. Anim. Prod. 5, 1–9.Google Scholar
National Reseaech Council (1957). Nutrient requirements of sheep. Publ. natn. Acad. Sci. natn. Res. Coun., Wash. No. 504.Google Scholar
Robinson, J. J. & Forbes, T. J. (1966). A study of the protein requirements of the mature breeding ewe. Maintenance requirements of the non-pregnant ewe. Br. J. Nutr. 20, 263–72.CrossRefGoogle ScholarPubMed
Robinson, J. J. & Forbes, T. J. (1967). A study of the protein requirements of the mature breeding ewe. II. Protein utilisation in the pregnant ewe. Br. J. Nutr. 21, 879–91.CrossRefGoogle Scholar
Vercoe, J. E. & Hall, W. B. (1965). The influence of the chemical composition of the diet on live-weight change in sheep. Aust. J. agric. Res. 16, 675–90.CrossRefGoogle Scholar