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Mineral retentions and body composition of grazing lambs

Published online by Cambridge University Press:  02 September 2010

J. K. Thompson
Affiliation:
School of Agriculture, 581 King Street, Aberdeen AB9 1UD
A. L. Gelman
Affiliation:
School of Agriculture, 581 King Street, Aberdeen AB9 1UD
J. R. Weddell
Affiliation:
School of Agriculture, 581 King Street, Aberdeen AB9 1UD
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Abstract

Growth rates and chemical compositions were measured with ram lambs grazing pure stands of perennial ryegrass, timothy, cocksfoot and tall fescue. A group of lambs slaughtered at the start of the trial enabled estimates to be made of the live-weight gains over the summer and the composition of these gains. The composition of the grass was also measured in samples taken at weekly intervals and estimates were made of the nutrients consumed from the different grass plots.

The quantities of ash, Ca, P and Mg in the empty bodies of the lambs were within the range of published values from similar studies. They support the contention that grass-fed lambs tend to have larger contents of ash, Ca and P in their empty bodies than concentrate-fed lambs of similar weight. Perennial ryegrass provided a superior diet in that lambs eating this grass grew more quickly, with leaner tissues and higher levels of ash, Ca and P in their empty-body gains. Lambs consuming tall fescue grew most slowly but their mineral contents were as large as the ryegrass-fed lambs when data were adjusted for differences in empty-body weight. Lambs fed on timothy or cocksfoot were the most poorly mineralized in spite of consuming considerably more Ca, P and Mg than the lambs on ryegrass. The data suggest that the efficiencies of absorption of Ca and P in ryegrass may be high, at about 0·64 for Ca and 0·71 for P.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1988

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References

REFERENCES

Agricultural Research Council. 1965. The Nutrient Requirements of Farm Livestock. No. 2, Ruminants. Agricultural Research Council, London.Google Scholar
Agricultural Research Council. 1980. The Nutrient Requirements of Ruminant Livestock. Commonwealth Agricultural Bureaux, Slough.Google Scholar
Bell, R. R., Tzeng, D. Y. and Draper, H. H. 1980. Long-term effects of calcium, phosphorus and forced exercise on the bones of mature mice. Journal of Nutrition 110: 11611168.CrossRefGoogle ScholarPubMed
Braithwaite, G. B. 1982. Endogenous faecal loss of calcium by ruminants. Journal of Agricultural Science. Cambridge 99: 355358.CrossRefGoogle Scholar
Burton, J. H. and Reid, J. T. 1969. Interrelationships among energy input, body size, age and body composition of sheep. Journal of Nutrition 97: 517524.CrossRefGoogle ScholarPubMed
Davidson, J. and McDonald, I. 1981. The effect of variation in dietary protein concentration and energy intake on mineral accretion in early-weaned lambs. Journal of Agricultural Science, Cambridge: 96 557560.CrossRefGoogle Scholar
Grace, N. D. 1983. Amounts and distribution of mineral elements associated with fleece-free empty body weight gains in the grazing sheep. New Zealand Journal of Agricultural Research 26: 5970.CrossRefGoogle Scholar
Guegubn, L. 1982. French recommended dietary allowances. Commission of Animal Nutrition. European Association of Animal Production, Leningrad, pp. 15.Google Scholar
Gueguen, L. and Demarouilii, C. 1965. Influence of the vegetative cycle and the growth stage on the mineral value of some herbage plants for adult sheep. Proceedings of 9th International Grassland Congress, Brazil pp. 745754.Google Scholar
Kellaway, R. C. 1973. The effects of plane of nutrition. genotype and sex on growth, body composition and wool production in grazing sheep. Journal of Agricultural Science. Cambridge 80: 1727.CrossRefGoogle Scholar
Langlands, J. P. and Sutherland, H. A. M. 1969. An estimate of the nutrients utilized for live-weight gain by Merino sheep. British Journal of Nutrition 23: 603609.CrossRefGoogle ScholarPubMed
Lawes Agricultural Trust. 1977. GENSTAT V, Mark 4-01. Rothamsted Experimental Station, Harpenden, Hertfordshire.Google Scholar
Perdoma, J. T., Shirley, R. L. and Chicco, C. F. 1977. Availability of nutrient minerals in four tropical forages fed freshly chopped to sheep. Journal of Animal Science 45: 11141119.CrossRefGoogle Scholar
Powell, K., Reid, R. L. and Balasko, J. A. 1978. Performance of lambs on perennial ryegrass, smooth bromegrass, orchardgrass and tall fescue pastures. II. Mineral utilization, in vitro digestibility and chemical composition of herbage. Journal of Animal Science 46: 15031514.CrossRefGoogle Scholar
Powley, G. and Johnson, C. L. 1977. Some effects of conservation of grass upon magnesium metabolism in sheep. Journal of Agricultural Science, Cambridge 88: 477482.CrossRefGoogle Scholar
Rattray, P. V., Garreti, W. N., Meyer, H. H., Bradford, G. E., East, N. E. and Hinman, N. 1973. Body and carcass composition of Targhee and Finn-Targhee lambs. Journal of Animal Science 37: 892897.CrossRefGoogle Scholar
Reid, R. L., Jung, G. A., Roemig, I. J. and Kocher, R. E. 1978. Mineral utilization by lambs and guinea pigs fed magnesium-fertilized grass and legume hays. Agronomy Journal 70: 914.CrossRefGoogle Scholar
Statistical Package for The Social Sciences. 1986. SPSS User's Guide. 2nd ed. SPSS Inc., Chicago.Google Scholar
Thompson, J. K. and Gelman, A. L. 1984. The absorption of calcium by forage-fed lambs. Proceedings of the Nutrition Society 43: 104A (Abstr.).Google Scholar
Thompson, J. K. and Warren, R. W. 1979. Variations in composition of pasture herbage. Grass and Forage Science 34: 8388.CrossRefGoogle Scholar