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Effect of species composition and sward structure on dietary quality in cattle and sheep grazing South African sourveld

Published online by Cambridge University Press:  27 March 2009

P. J. O'Reagain
Affiliation:
Döhne Agricultural Development Institute, Private Bag XI5, Stutterheim 4930, South Africa
R. N. Owen-Smith
Affiliation:
Centre for African Ecology, University of the Witwatersrand, PO Wits 2050, South Africa

Summary

The effect of sward structure and species composition on dietary quality in cattle and sheep grazing a mesic, low quality grassland (sourveld) in South Africa was investigated over the 1990/91 and 1991/92 grazing seasons. Species composition had no measurable effect on dietary quality in either cattle or sheep but this variable could affect quality over grazing periods longer than those used in the study. In contrast, sward structure, and in particular sward greenness, had a major effect on dietary quality in both animals. Dietary in vitro digestibility (IVD) was positively correlated (P < 0·001) with sward greenness but negatively correlated (P < 0·05) with herbage mass and sward height. Dietary IVD in sheep was consistently higher (P < 0·001) then in cattle but both species reacted in a similar manner to changes in sward structure and season. Dietary quality declined over the grazing season, with IVD being highest in spring (> 60%) and lowest in winter (< 45%). Marked intra-seasonal fluctuations in quality also occurred in response to sward structure and apparent variation in soil moisture. Fire also appeared to have a significant effect on quality, with IVD being higher (P < 0·001) in the first year following the burn than in the subsequent year. It is suggested that on sourveld, dietary quality in the growing season is determined by a combination of environmental and management factors. Conversely, in the dormant season, dietary quality is largely determined by environmental factors beyond the control of the grazier.

Type
Animals
Copyright
Copyright © Cambridge University Press 1996

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References

REFERENCES

Acocks, J. P. H. (1988). Veld types ofSouth Africa. Memoirs of the Botanical Survey of South Africa 57. Pretoria: Government Printer.Google Scholar
Association of Official Agricultural Chemists (1970). Official Methods of Analysis, 9th Edn.Washington, DC: Association of Official Agricultural Chemists.Google Scholar
Barnes, G. R. (1989). Management of veld types: sour grassveld. In Veld Management in the Eastern Cape (Eds Danckwerts, J. E. & Teague, W. R.), pp. 149155. Pretoria: Government Printer.Google Scholar
Barthram, G. T. (1981). Sward structure and the depth of the grazed horizon. Grass and Forage Science 36, 130131.Google Scholar
Birch, H. F. (1958). Pattern of humus decomposition in East African soils. Nature 181, 788.CrossRefGoogle Scholar
Birch, H. F. (1960). Nitrification in soils after different periods of dryness. Plant and Soil 12, 8196.CrossRefGoogle Scholar
Bransby, D. I. & Tainton, N. M. (1977). The disc pasture meter: possible application in grazing management. Proceedings of the Grassland Society of Southern Africa 12, 115118.CrossRefGoogle Scholar
Chacon, E. A., Stobbs, T. H. & Dale, M. B. (1978). Influence of sward characteristics on grazing behaviour and growth of Hereford steers grazing tropical grass pastures. Australian Journal of Agricultural Research 29, 89102.CrossRefGoogle Scholar
Dradu, E. A. A. & Harrington, G. N. (1972). Seasonal crude protein content of samples obtained from a tropical range pasture using oesophageal fistulated steers. East African Agricultural and Forestry Journal 56, 5661.CrossRefGoogle Scholar
Dyksterhuis, E. J. (1958). Ecological principles in range evaluation. Botanical Review 24, 253272.CrossRefGoogle Scholar
Engels, E. A. N. & Van der Merwe, F. J. (1967). The application of an in vitro technique to South African forages with special reference to the effect of certain factors on the results. South African Journal of Agricultural Science 10, 983987.Google Scholar
Foran, B. D., Tainton, N. M. & Booysen, P. De V. (1978). The development of a method for assessing veld condition in three grassveld types in Natal. Proceedings of the Grassland Society of Southern Africa 13, 2733.CrossRefGoogle Scholar
Forbes, T. D. A. (1982). Ingestive behaviour and diet selection in grazing cattle and sheep. PhD thesis, University of Edinburgh.Google Scholar
Forbes, T. D. A. & Coleman, S. W. (1993). Forage intake and ingestive behaviour of cattle grazing old world bluestems. Agronomy Journal 85, 808816.CrossRefGoogle Scholar
Gibbs Russell, G. E., Watson, L., Koekemoer, M., Smook, L., Barber, N. P., Anderson, H. M. & Dalling, M. J. (1990). Grasses of southern Africa. Memoirs of the Botanical Survey of South Africa 58. National Botanic Gardens, South Africa.Google Scholar
Grant, S. A., Suckling, D. E., Smith, H. K., Torvell, L., Forbes, T. D. A. & Hodgson, J. (1985). Comparative studies of diet selection by sheep and cattle: the hill grasslands. Journal of Ecology 73, 9871004.CrossRefGoogle Scholar
Grieve, C. M. & Osbourn, D. F. (1965). The nutritional value of some tropical grasses. Journal of Agricultural Science, Cambridge 65, 411417.CrossRefGoogle Scholar
Hanley, T. A. (1982). The nutritional basis for food selection by ungulates. Journal of Range Management 35, 146151.CrossRefGoogle Scholar
Hardy, M. B. (1986). Grazing dynamics in Highland Sourveld. MSc thesis, University of Natal, Pietermaritzburg.Google Scholar
Heckathorn, S. A. & Delucia, E. H. (1994). Drought induced nitrogen retranslocation in perennial C4, grasses of tallgrass prairie. Ecology 75, 18771886.CrossRefGoogle Scholar
Hodgson, J. & Maxwell, T. J. (1981). Grazing research and grazing management. Hill Farming Research Organisation Biennial Report, 1979–1981. Edinburgh: HFRO.Google Scholar
Juko, C. D. & Bredon, R. M. (1961). The chemical composition of leaves and whole plant as an indicator of the range of available nutrients for selective grazing by cattle. Tropical Agriculture (Trinidad) 38, 179187.Google Scholar
Jung, H. G. & Koong, L. J. (1985). Effects of hunger satiation on diet quality by grazing sheep. Journal of Range Management 38, 302305.CrossRefGoogle Scholar
McKay, A. D. & Frandsen, P. E. (1969). Chemical and floristic components of the diet of Zebu cattle (Bos indicus) in browse and grass range pastures in a semi-arid upland area of Kenya. I – Crude protein. Tropical Agriculture (Trinidad) 46, 279291.Google Scholar
Mentis, M. T. (1982). A simulation of the grazing of sour grassveld. PhD thesis, University of Natal, Pietermaritzburg.Google Scholar
Mes, M. G. (1958). The influence of veld burning or mowing on the water, nitrogen and ash content of grasses. South African Journal of Science 54, 8386.Google Scholar
Ocumpaugh, W. R. & Matches, A. G. (1977). Autumnwinter yield and quality of tall fescue. Agronomy Journal 69, 639643.CrossRefGoogle Scholar
O'Reagain, P. J. (1994). The effect of sward structure and species composition on dietary quality and intake in cattle and sheep grazing the Dohne Sourveld. PhD thesis, University of the Witwatersrand, Johannesburg.Google Scholar
O'Reagain, P. J. & Grau, E. A. (1995). Sequence of species selection by cattle and sheep on South African sourveld. Journal of Range Management 48, 314321.CrossRefGoogle Scholar
O'Reagain, P. J. & Mentis, M. T. (1988). Seasonal changes in the quality of diet selected by cattle grazing the Natal Sour Sandveld. Journal of the Grassland Society of Southern Africa 5, 4851.CrossRefGoogle Scholar
O'Reagain, P. J. & Mentis, M. T. (1990). The effect of veld condition on the quality of diet selected by cattle grazing the Natal Sour Sandveld. Journal of the Grassland Society of Southern Africa 7, 190195.CrossRefGoogle Scholar
O'Reagain, P. J., Goetsch, B. C. & Owen-Smith, R. N. (1995). Ruminal degradation characteristics of some African rangeland grasses. Journal of Agricultural Science, Cambridge 125, 189197.CrossRefGoogle Scholar
O'Reagain, P. J., Goetsch, B. C. & Owen-Smith, R. N. (1996). Effect of species composition and sward structure on the ingestive behaviour of cattle and sheep grazing South African sourveld. Journal of Agricultural Science 127, 271280.CrossRefGoogle Scholar
Roux, E. (1969). Grass: a Story of Frankenwald. Cape Town: Oxford University Press.Google Scholar
SAS Institute (1991). SAS/STAT User's Guide, Release 6.03, 6th Edn. Cary, NC: SAS Institute.Google Scholar
Semb, G. & Robinson, J. B. D. (1969). The natural nitrogen flush in different arable soils and climates in East Africa. East African Agriculture and Forestry Journal 34, 350370.CrossRefGoogle Scholar
Sharrow, S. H. & Wright, H. A. (1976). Effects of fire, ash and litter on soil nitrate, temperature, moisture and tobosagrass production in the rolling plains. Journal of Range Management 30, 266270.CrossRefGoogle Scholar
Sokal, R. R. & Rohlf, F. J. (1981). Biometry. New York: W. H. Freeman.Google Scholar
Tainton, N. M. (1981). The ecology of the main grazing lands of South Africa. In Veld and Pasture Management in South Africa (Ed. Tainton, N. M.), pp. 2555. Pietermaritzburg: Shuter and Shooter.Google Scholar
Tainton, N. M. (1986). A system for assessing range condition in South Africa. In Rangelands: a Resource under Siege (Eds Joss, P. J., Lynch, P. W. & Williams, O. B.), p. 524. Proceedings of the 2nd International Rangeland Congress. Canberra: Australian Academy of Sciences.Google Scholar
Tainton, N. M., Edwards, P. J. & Mentis, M. T. (1980). A revised method of assessing veld condition. Proceedings of the Grassland Society of Southern Africa 15, 3742.CrossRefGoogle Scholar
Weinmann, H. (1942). On the autumnal remigration of nitrogen and phosphorus in Trachypogon plumosus. Journal of South African Botany 8, 179196.Google Scholar
Wilson, J. R. (1976). Variation of leaf characteristics with level of insertion on a grass tiller. I. Development rate, chemical composition and dry matter digestibility. Australian Journal of Agricultural Research 27, 343354.CrossRefGoogle Scholar
Wilson, J. R. (1981). Environmental and nutritional factors affecting herbage quality. In Nutritional Limits to Animal Production from Pastures (Ed. Hacker, J. B.), pp. 111129.St. Lucia: Commonwealth Agricultural Bureau.Google Scholar