Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-29T12:50:05.109Z Has data issue: false hasContentIssue false

Not all sheep prefer clover: diet selection revisited

Published online by Cambridge University Press:  27 March 2009

J. A. Newman
Affiliation:
AFRC Unit of Ecology and Behaviour, Department of Zoology, University of Oxford, South Parks Road, Oxford 0X1 3PS, UK
A. J. Parsons
Affiliation:
AFRC Institute of Grassland and Environmental Research, Hurley, Maidenhead, Berks SL6 5LR, UK
A. Harvey
Affiliation:
AFRC Institute of Grassland and Environmental Research, Hurley, Maidenhead, Berks SL6 5LR, UK

Summary

Several previous studies have shown that the proportion of clover in sheep diets was greater than the proportion of clover in the mixed species swards being grazed. Various hypotheses have been put forward to explain this observation. One widely held hypothesis is that sheep prefer (actively select) clover to grass. This hypothesis was tested by offering 12 sheep, six that had been recently grazing perennial ryegrass and six that had recently been grazing white clover, the choice between foraging on grass or clover provided as turves. It was found that, rather than prefer clover, the sheep preferred the opposite species to the one they had previously grazed. From these observations, alternative hypotheses are proposed to explain the disparity in composition of the diet relative to the swards observed in previous studies, and the evidence for a constant preference for clover and its basis in grazing behaviour is reconsidered.

Type
Animals
Copyright
Copyright © Cambridge University Press 1992

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Allen, J. A. (1972). Evidence for stabilizing and apostatic selection by wild blackbirds. Nature 237, 348349.CrossRefGoogle ScholarPubMed
Arnold, G. W. (1960). The effect of the quantity and quality of pasture available to sheep on their grazing behaviour. Australian Journal of Agricultural Research 11, 10341043.CrossRefGoogle Scholar
Arnold, G. W. (1987). Influence of the biomass, botanical composition and sward height of annual pastures on foraging behaviour by sheep. Journal of Applied Ecology 24, 759772.Google Scholar
Arnold, G. W., Ball, J., Mcmanus, W. R. & Bush, I. G. (1966). Studies on the diet of the grazing animal. I. Seasonal changes in the diet of sheep grazing pastures of different availability and composition. Australian Journal of Agricultural Research 17, 543556.Google Scholar
Baumont, R., Brun, J. P. & Dulphy, J. P. (1989). Influence of the nature of hay on its ingestibility and the kinetics of intake during large meals in sheep and cows. In XVIth International Grassland Congress, Nice, France (Ed. Jarrige, R.), pp. 787788. Versailles: French Grassland Society.Google Scholar
Bedell, T. E. (1968). Seasonal forage preferences of grazing cattle and sheep in western Oregon. Journal of Range Management 21, 291297.Google Scholar
Bedell, T. E. (1973). Botanical composition of subclover-grass pastures as affected by single and dual grazing by cattle and sheep. Agronomy Journal 65, 502504.Google Scholar
Bootsma, A., Ataja, A. M. & Hodgson, J. (1990). Diet selection by deer grazing mixed ryegrass/white clover pastures. Proceedings of the New Zeland Grassland Association 51, 187190.Google Scholar
Briseño, De La Hoz V. M. & Wilman, D. (1981). Effects of cattle grazing, sheep grazing, cutting and sward height on a grass-white clover sward. Journal of Agricultural Science, Cambridge 97, 699706.CrossRefGoogle Scholar
Clark, D. A. & Harris, P. S. (1985). Composition of the diet of sheep grazing swards of differing white clover content and spatial distribution. New Zealand Journal of Agricultural Research 28, 233240.CrossRefGoogle Scholar
Clark, D. A., Lambert, M. G. & Chapman, D. F. (1982). Pasture management and hill country production. Proceedings of the New Zealand Grassland Association 43, 205214.Google Scholar
Curll, M. L. & Gleeson, A. C. (1987). The introduction of red or white clover into a perennial grass sward. Grass and Forage Science 42, 397403.CrossRefGoogle Scholar
Curll, M. L. & Wilkins, R. J. (1980). The relationship between selective grazing by sheep and the botanical composition of a grass/clover sward. In European Grass-land Federation General Meeting Proceedings, Forage Production Under Marginal Conditions, pp. 7.17–7.23.Google Scholar
Curll, M. L., Wilkins, R. J., Snaydon, R. W. & Shanmugalingam, V. S. (1985). The effects of stocking rate and nitrogen fertilizer on a perennial ryegrass-white clover sward. I. Sward and sheep performance. Grass and Forage Science 40, 129140.Google Scholar
Davis, I. F. (1964). Diet selected by sheep grazing on annual pasture in southern Victoria. Proceedings of the Australian Society of Animal Production 5, 249250.Google Scholar
Dougherty, C. T., Bradley, N. W., Cornelius, P. L. & Lauriault, L. M. (1987). Herbage intake rates of beef cattle grazing alfalfa. Agronomy Journal 79, 10031008.CrossRefGoogle Scholar
Forbes, J. M., Wright, J. A. & Bannister, A. (1972). A note on rate of eating in sheep. Animal Production 15, 211214.Google Scholar
Frame, J. (1987). The role of white clover in United Kingdom pastures. Outlook in Agriculture 16, 2834.Google Scholar
Frame, J. & Newbould, P. (1986). Agronomy of white clover. Advances in Agronomy 40, 188.Google Scholar
Gibb, M. J. & Treacher, T. T. (1983). The performance of lactating ewes offered diets containing different proportions of fresh perennial ryegrass and white clover. Animal Production 37, 433440.Google Scholar
Gibb, M. J. & Treacher, T. T. (1984). The performance of weaned lambs offered diets containing different proportions of fresh perennial ryegrass and white clover. Animal Production 39, 413420.Google Scholar
Grimes, R. C., Watkin, B. R. & Gallagher, J. R. (1966). An evaluation of pasture quality with young grazing sheep. II. Chemical composition, botanical composition and in vitro digestibility of herbage selected by oesophageal-fistulated sheep. Journal of Agricultural Science Cambridge 66, 113119.Google Scholar
Hamilton, B. A., Hutchinson, K. J., Annis, P. C. & Donnelly, J. B. (1973). Relationships between the diet selected by grazing sheep and the herbage on offer. Australian Journal of Agricultural Research 24, 271277.CrossRefGoogle Scholar
Hodge, R. W. & Doyle, J. J. (1967). Diet selected by lambs and yearling sheep grazing on annual and perennial pastures in southern Victoria, Australian Journal of Experimental Agriculture and Animal Husbandry 7, 141143.CrossRefGoogle Scholar
Hodgson, J. (1979). Nomenclature and definitions in grazing studies. Grass and Forage Science 34, 1118.Google Scholar
Hodgson, J. (1990). Grazing Management, Science into Practice. New York: Longman Scientific & Technical.Google Scholar
Illius, A. W. & Gordon, I. J. (1990). Constraints on diet selection and foraging behaviour in mammalian herbivores. In Behavioural Mechanisms of Food Selection (Ed. Hughes, R. N.), pp. 369392. Heidelberg, New York: NATO ASI Series G: Ecological Sciences, Springer-Verlag.Google Scholar
Illius, A. W., Clark, D. A. & Hodgson, J. (1992). Discrimination and patch choice by sheep grazing grass-clover swards. Journal of Animal Ecology 61, 183194.Google Scholar
Johnson, I. R., Parsons, A. J. & Ludlow, M. M. (1989). Modelling photosynthesis in monocultures and mixtures. Australian Journal of Plant Physiology 16, 501516.Google Scholar
Kenney, P. A. & Black, J. L. (1984). Factors affecting diet selection by sheep. I. Potential intake rate and acceptability of feed. Australian Journal of Agricultural Research 35, 551563.Google Scholar
L'huillier, P. J., Poppi, D. P. & Fraser, T. J. (1984). Influence of green leaf distribution on diet selection by sheep and the implications for animal performance. Proceedings of the New Zealand Society of Animal Production 44, 105107.Google Scholar
L'huillier, P. J., Poppi, D. P. & Fraser, T. J. (1986). Influence of structure and composition of ryegrass and prairie grass-white clover swards on the grazed horizon and diet harvested by sheep. Grass and Forage Science 41, 259267.CrossRefGoogle Scholar
Laidlaw, A. S. & Steen, R. W. J. (1989). Turnover of grass laminae and white clover leaves in mixed swards continuously grazed with steers at high- and low-N fertilizer levels. Grass and Forage Science 44, 249258.Google Scholar
Lascano, C. E. & Thomas, D. (1988). Forage quality and animal selection of Arachis pinloi in association with tropical grasses in the eastern plains of Colombia. Grass and Forage Science 43, 433439.CrossRefGoogle Scholar
Leigh, J. H. & Holgate, M. D. (1978). Effects of pasture availability on the composition and quality of the diet selected by sheep grazing native, degenerate and improved pastures in the Upper Shoalhaven Valley, New South Wales. Australian Journal of Experimental Agriculture and Animal Husbandry 18, 381390.Google Scholar
Mccleery, R. H. (1977). On the nature of satiation curves. Animal Behaviour 25, 10051015.Google Scholar
Meyer, J. H., Lofgreen, G. P. & Hull, J. L. (1957). Selective grazing by sheep and cattle. Journal of Animal Science 16, 766772.Google Scholar
Milne, J. A., Hodgson, J., Thompson, R., Souter, W. G. & Barthram, G. T. (1982). The diet ingested by sheep grazing swards differing in white clover and perennial ryegrass content. Grass and Forage Science 37, 209218.Google Scholar
Parsons, A. J., Harvey, A. & Woledge, J. (1991 a). Plant-animal interactions in a continuously grazed mixture. 1. Differences in the physiology of leaf expansion and the fate of leaves of grass and clover. Journal of Applied Ecology 28, 619634.Google Scholar
Parsons, A. J., Harvey, A. & Johnson, I. R. (1991 b). Plant-animal interactions in a continuously grazed mixture. II. The role of differences in the physiology of plant growth and of selective grazing on the performance and stability of species in a mixture. Journal of Applied Ecology 28, 635658.Google Scholar
Penning, P. D. & Hooper, G. E. (1985). An evaluation of the use of short-term weight changes in growing sheep for estimating herbage intake. Grass and Forage Science 40, 7984.Google Scholar
Penning, P. D., Parsons, A. J., Orr, R. J. & Treacher, T. T. (1991 a). Intake and behaviour responses by sheep to changes in sward characteristics under continuous stocking. Grass and Forage Science 46, 1528.CrossRefGoogle Scholar
Penning, P. D., Rook, A. J. & Orr, R. J. (1991 b). Patterns of ingestive behaviour of sheep continuously stocked on monocultures of ryegrass or white clover. Applied Animal Behaviour Science 31, 237250.Google Scholar
Provenza, F. D. & Balph, D. F. (1990). Applicability of five diet-selection models to various foraging challenges ruminants encounter. In Behavioural Mechanisms of Food Selection (Ed. Hughes, R. N.), pp. 423459. Heidelberg, New York: NATO ASI Series G: Ecological Sciences, Springer-Verlag.Google Scholar
Rae, A. L., Brougham, R. W., Glenday, A. C. & Butler, G. W. (1963). Pasture type in relation to live-weight gain, carcass composition, iodine nutrition and some rumen characteristics of sheep. I. Live-weight growth of the sheep. Journal of Agricultural Science, Cambridge 61, 187190.Google Scholar
Ridout, M. S. & Robson, M. J. (1991). Composition of the diet of sheep grazing swards of differing white clover content and spatial distribution: a re-evaluation. New Zealand Journal of Agricultural Research 34, 8993.Google Scholar
Rook, A. J. & Penning, P. D. (1991). Stochastic models of grazing behaviour in sheep. Applied Animal Behaviour Science 32, 167177.Google Scholar
Thomson, D. J. (1977). The role of legumes in improving the quality of forage diets. In Proceedings of the International Meeting on Animal Production from Temperate Grassland (Ed. Gilsenan, B.), pp. 131135. Dublin: An Foras Taluntais.Google Scholar
Thomson, D. J. (1978). Effect of the proportion of legumes in the sward on animal output. In Changes in Sward Composition and Productivity (Eds Charles, A. H. & Haggar, R. J.), pp. 101109. Hurley: British Grassland Society.Google Scholar
Tuttle, E. M., Wulfson, L. & Caraco, T. (1990). Risk-aversion, relative abundance of resources and foraging preference. Behavioral Ecology and Sociobiology 26, 165172.Google Scholar
Ulyatt, M. J. (1971). Studies on the causes of the differences in pasture quality between perennial ryegrass, short-rotation ryegrass, and white clover. New Zealand Journal of Agricultural Research 14, 352367.Google Scholar
Vallentine, J. F. (1990). Grazing Management. San Diego: Academic Press.Google Scholar
Van Dyne, G. M. & Heady, H. F. (1965). Botanical composition of sheep and cattle diets on a mature annual range. Hilgardia 36, 465492.Google Scholar
Watkin, B. R. & Clements, R. J. (1978). The effects of grazing animals on pastures. In Plant Relations in Pastures (Ed Wilson, J. R.), pp. 273289. Australia: CSIRO.Google Scholar
Weir, W. C. & Torell, D. T. (1959). Selective grazing by sheep as shown by a comparison of the chemical composition of range and pasture forage obtained by hand clipping and that collected by esophageal-fistulated sheep. Journal of Animal Science 18, 641649.Google Scholar
Westoby, M. (1974). An analysis of diet selection by large generalist herbivores. The American Naturalist 108, 290304.Google Scholar
Wilman, D. & Simpson, D. (1988). The growth of white clover (Trifolium repens) in five sown hill swards grazed by sheep. Journal of Applied Ecology 25, 631642.Google Scholar
Wilson, A. D. (1963). The effect of diet on secretion of parotid saliva by sheep. III. Observations of the secretion of saliva by sheep. Australian Journal of Agricultural Research 14, 808814.Google Scholar