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The effect of pelleting on the voluntary intake and digestibility of leaf and stem fractions of three grasses

Published online by Cambridge University Press:  25 March 2008

M. A. Laredo
Affiliation:
Division of Tropical Agronomy, CSIRO, Cunningham Laboratory, St Lucia, Queensland, Australia
D. J. Minson
Affiliation:
Division of Tropical Agronomy, CSIRO, Cunningham Laboratory, St Lucia, Queensland, Australia
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Abstract

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1. Leaf is eaten in greater quantities than stem of similar digestibility. To determine whether this difference is caused by physical or chemical factors, leaf and stem fractions from Digitaria decumbens, Chloris gayana and Setaria splendida were fed ad lib. to sheep in the chopped and pelleted forms. Pellets were made from leaf and stem which had been ground through a screen with 3 mm holes. All sheep received a protein and mineral supplement

2. Voluntary intake of chopped leaf was 34% higher than that of the chopped stem fraction (40·3 and 30·0 g/kg body-weight0·75 respectively, P < 0·01) although dry matter digestibility ratios were similar (0·478 and 0·450 respectively, P > 0·05). The higher intake of leaf was associated with a larger surface area (13400 and 5200 mm2/g for chopped leaf and stem respectively), lower bulk density (60 and 180 kg/m3 respectively) and lower neutral-detergent fibre (706 and 724 g/kg respectively), acid-detergent fibre (383 and 413 g/kg respectively) and lignin (42 and 59 g/kg respectively) contents. Chopped leaf was retained in the reticulo-rumen for a shorter time than the stem fraction (19·9 and 26·4 h respectively)

3. Grinding and pelleting increased the voluntary intake of the leaf fraction by 88% and the stem fraction by 60%. This increased voluntary intake caused by grinding and pelleting was not accompanied by any significant changes in the chemical composition of the diet. Grinding and pelleting reduced the time that the food was retained in the reticulo-rumen and this change appeared sufficient to account for the observed increases in voluntary intake

4. It was concluded that the higher intake of the leaf fraction of grasses is caused by differences in retention time of food in the reticulo-rumen. These differences in retention time are caused by differences in physical properties and not chemical composition.

Type
General Nutrition
Copyright
Copyright © The Nutrition Society 1975

References

American Society of Agricultural Engineers (1967). Agricultural Engineers' Yearbook, 1967 p. 301.Google Scholar
Association of Official Agricultural Chemists (1965). Official Methods of Analysis 10th ed., p. 16. Washington, DC: Association of Official Agricultural Chemists.Google Scholar
Baumgardt, B. R. (1970). In Physiology of Digestion and Metabolism in the Ruminant p. 235 [Phillipson, A. T, editor]. Newcastle upon Tyne: Oriel Press.Google Scholar
Clancy, M. J. & Wilson, R. C. (1966). Proc. 10th int. Grassld Congr., Helsinki p. 445.Google Scholar
Dehority, B. A. & Johnson, R. R. (1960). J. Anim. Sci. 19, 1257.CrossRefGoogle Scholar
Greenhalgh, J. F. D. & Reid, G. W. (1971). Br. J. Nutr. 26, 107.CrossRefGoogle Scholar
Greenhalgh, J. F. D. & Reid, G. W. (1973). Anim. Prod. 16, 223.Google Scholar
Harmond, J. E., Klein, I. M. & Branderberg, N. R. (1961). Agric. Handb. Forest Serv. U. S. no. 179.Google Scholar
Johnson, A. D. & Simons, J. G. (1972). Communs Soil Sci. Plant Analysis 3, 1.Google Scholar
Laredo, M. A. (1975). The voluntary intake by sheep given separated leaf and stem fractions of tropical grasses. PhD Thesis, University of Queensland.Google Scholar
Laredo, M. A. & Minson, D. J. (1973). Aust. J. agric. Res. 24, 875.CrossRefGoogle Scholar
McLeod, M. N. & Minson, D. J. (1971). J. Br. Grassld Soc. 26, 251.Google Scholar
Milford, R. & Minson, D. J. (1966). Proc. 9th int. Grassld Congr., Sao Paulo, Brazil p. 815.Google Scholar
Milford, R. & Minson, D. J. (1968). Aust. J. exp. Agric. Anim. Husb. 8, 413.CrossRefGoogle Scholar
Minson, D. J. (1966). Br. J. Nutr. 20, 765.CrossRefGoogle Scholar
Minson, D. J. (1967). Br. J. Nutr. 21, 587.Google Scholar
Minson, D. J. & Cowper, J. L. (1966). Br. J. Nutr. 20, 757.CrossRefGoogle Scholar
Minson, D. J. & Milford, R. (1967). J. Br. Grassld Soc. 22, 170.CrossRefGoogle Scholar
Minson, D. J. & Milford, R. (1969). J. agric. Sci., Camb. 71, 381.CrossRefGoogle Scholar
Monson, W. G., Powell, J. B. & Burton, G. W. (1972). Agron. J. 64, 231.CrossRefGoogle Scholar
Tetlow, R. M. & Wilkins, R. J. (1972). Anim. Prod. 14, 335.Google Scholar
Thornton, R. F. & Minson, D. J. (1972). Aust. J. agric. Res. 23, 871.CrossRefGoogle Scholar
Tilley, J. M. A. & Terry, R. A. (1963). J. Br. Grassld Soc. 18, 104.Google Scholar
Van Soest, P. J. (1963). J. Ass. off. agric. Chem. 46, 825.Google Scholar
Weston, R. H. (1959). Aust. J. agric. Res. 10, 865.CrossRefGoogle Scholar
Wilkins, R. J., Lonsdale, C. R., Tetlow, R. M. & Forrest, T. J. (1972). Anim. Prod. 14, 177.Google Scholar