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Fine-scale discrimination of forage quality by sheep offered a soyabean meal or barley supplement while grazing a nitrogen-fertilized heather (Calluna vulgaris) mosaic

Published online by Cambridge University Press:  27 March 2009

A.J. Duncan
Affiliation:
MaCaulay Land Use Research Institute, Craigiebuckler, Aberdeen AB9 2QJ, UK
S. E. Hartley
Affiliation:
Institute of Terrestrial Ecology, Banchory, Kincardineshire AB3I 4BY, UK
G. R. Iason
Affiliation:
MaCaulay Land Use Research Institute, Craigiebuckler, Aberdeen AB9 2QJ, UK

Summary

The ability of 12 Scottish Blackface ewes to discriminate and concentrate grazing activity in nitrogenfertilized heather patches was determined. The nitrogen content of a stand of heather (Calluna vulgaris) was increased and the fibre content decreased by adding ammonium nitrate fertilizer (7·5 g N/m2) 3 months prior to grazing, in Scotland during August 1991, to selected areas within a patchwork array. The sheep were offered either a high protein (300 g soyabean meal) or low protein (285 g ground barley) supplement daily before being allowed to graze within the heather mosaic during November 1991. The proportion of time spent grazing in fertilized and control patches (patch selection) and the proportion of daylight hours spent grazing (proportion of time spent grazing) was estimated for individual sheep for 6 days. Rumen ammonia concentrations were determined at the end of the grazing period. All animals spent approximately twice as much time grazing in fertilized as in control patches. About half of the daylight hours were spent grazing. The nature of the supplement did not influence patch selection, the proportion of time spent grazing or rumen ammonia concentrations. It was concluded that sheep are able to discern differences in the chemical composition of heather on a fine scale and that their foraging behaviour is not influenced by the type of supplement offered.

Type
Animals
Copyright
Copyright © Cambridge University Press 1994

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References

Agricultural Research Council (1980). The Nutrient Requirements of Ruminant Livestock. Farnham Royal: Commonwealth Agricultural Bureaux.Google Scholar
Arnold, G. W. (1981). Grazing behaviour. In Grazing Animals(Ed. Morley, F. H. W.), pp. 79104. Amsterdam: Elsevier.Google Scholar
Asquith, T. N. & Butler, L. G. (1985). Use of dye-labeled protein as spectrophotometric assay for protein precipitants such as tannin. Journal of Chemical Ecology 11, 15351544.CrossRefGoogle ScholarPubMed
Chapman, B., Cooke, G. H. & Whitehead, R. (1967). Automated analysis: improved method for determination of ammoniacal nitrogen. Water Pollution Control 66, 280281.Google Scholar
Clutton Brock, T. H., Iason, G. R., Albon, S. D. & Guinness, F. E. (1982). Effects of lactation on feeding behaviour and habitat use in wild red deer hinds. Journal of Zoology 198, 227236.CrossRefGoogle Scholar
Delcurto, T., Cochran, R. C., Corah, L. R., Beharka, A. A., Vanzant, E. S. & Johnson, D. E. (1990). Supplementation of dormant tallgrass-prairie forage. II. Performance and forage utilization characteristics in grazing beef cattle receiving supplements of different protein concentrations. Journal of Animal Science 68, 532542.CrossRefGoogle ScholarPubMed
Gimingham, C. H. (1972). Ecology of Heathlands. London: Chapman and Hall.Google Scholar
Grant, S. A., Milne, J. A., Barthram, G. T. & Souter, W. G. (1982). Effects of season and level of grazing on the utilization of heather by sheep. 3. Longer-term responses and sward recovery. Grass and Forage Science 37, 311320.CrossRefGoogle Scholar
Iason, G. R. & Hester, A. J. (1992). The response of heather (Calluna vulgaris) to shade and nutrients: predictions of the carbon-nutrient balance hypothesis. Journal of Ecology 81, 7580.CrossRefGoogle Scholar
Iason, G. R., Hartley, S. E. & Duncan, A. J. (1993). Chemical composition of Calluna vulgaris(Ericaceae): Do responses to fertilizer vary with phenological stage? Biochemical Systematics and Ecology 21, 315321.CrossRefGoogle Scholar
Illius, A. W., Clark, D. A. & Hodgson, J. (1992). Discrimination and patch choice by sheep grazing grassclover swards. Journal of Animal Ecology 61, 183194.CrossRefGoogle Scholar
Jaramillo, V. J. & Detling, J. K. (1992 a). Small-scale heterogeneity in a semi-arid North American grassland. I. Tillering, N uptake and retranslocation in simulated urine patches. Journal of Applied Ecology 29, 18.CrossRefGoogle Scholar
Jaramillo, V. J. & Detling, J. K. (1992 b). Small-scale heterogeneity in a semi-arid North American grassland. 11. Cattle grazing of simulated urine patches. Journal of Applied Ecology 29, 913.CrossRefGoogle Scholar
Judkins, M. B., Krysl, L. J., Wallace, J. D., Galyean, M. L., Jones, K. D. & Parker, E. E. (1985). Intake and diet selection by protein supplemented grazing steers. Journal of Range Management 38, 210214.CrossRefGoogle Scholar
Kyriazakis, I. & Emmans, G. C. (1991). Diet selection in pigs: dietary choices made by growing pigs following a period of underfeeding with protein. Animal Production 52, 337346.Google Scholar
Kyriazakis, I. & Oldham, J. D. (1993). Diet selection in sheep: the ability of growing lambs to select a diet that meets their crude protein (nitrogen x 6·25) requirements. British Journal of Nutrition 69, 617629.CrossRefGoogle ScholarPubMed
Lawes Agricultural Trust (1989). Genstat 5 Committee of the Statistics Department, Rothamsted Experimental Station. Oxford: Oxford University Press.Google Scholar
Marriott, C. A., Smith, M. A. & Baird, M. A. (1987). The effect of sheep urine on clover performance in a grazed upland sward. Journal of Agricultural Science, Cambridge 109, 177185.CrossRefGoogle Scholar
Martin, P. & Bateson, P. (1986). Measuring Behaviour: An Introductory Guide. Cambridge: Cambridge University Press.Google Scholar
Miller, G. R. (1968). Evidence for selective feeding on fertilized plots by red grouse, hares and rabbits. Journal of Wildlife Management 32, 849853.CrossRefGoogle Scholar
Milne, J. A. (1974). The effect of season and age of stand on the nutritive value of heather (Calluna vulgaris, L. Hull) to sheep. Journal of Agricultural Science, Cambridge 83, 281288.CrossRefGoogle Scholar
Milne, J. A., Christie, A. & Russel, A. J. F. (1979). The effects of nitrogen and energy supplementation on the voluntary intake and digestion of heather by sheep. Journal of Agricultural Science, Cambridge 92, 635643.CrossRefGoogle Scholar
Mole, S. & Waterman, P. G. (1987). A critical analysis of techniques for measuring tannins in ecological studies. I. Techniques for chemically defining tannins. Oecologia 72, 137147.CrossRefGoogle ScholarPubMed
Moss, R. & Hewson, R. (1985). Effects on heather of heavy grazing by mountain hares. Holarctic Ecology 8, 280284.Google Scholar
Price, M. L. & Butler, L. G. (1977). Rapid visual estimation and spectrophotometric determination of tannin content of sorghum grain. Journal of Agricultural and Food Chemistry 25, 12681273.CrossRefGoogle Scholar
Price, P. W., Waring, G. L., Julkunen-Tiitto, R., Tahvanainen, J., Mooney, H. A. & Craig, T. P. (1989). Carbon-nutrient balance hypothesis in within-species phytochemical variation of Salix lasiolepis. Journal of Chemical Ecology 15, 11171131.CrossRefGoogle ScholarPubMed
Robbins, C. T., Hagerman, A. E., Hjelijord, O. & Baker, D. L. (1987). Role of tannins in defending plants against ruminants: reduction in protein availability. Ecology 68, 98107.CrossRefGoogle Scholar
Rozin, P. (1976). The selection of foods by rats, humans, and other animals. Advances in the Study of Behavior 6, 2176.CrossRefGoogle Scholar
Van Soest, P. J. (1963). Use of detergents in the analysis of fibrous feeds. II. A rapid method for the determination of fiber and lignin. Journal of the Association of Official Analytical Chemists 46, 829835.Google Scholar
Van Soest, P. J. & Wine, R. H. (1967). Use of detergents in the analysis of fibrous feeds. IV. Determination of plant cell-wall constituents. Journal of the Association of Official Analytical Chemists 50, 5055.Google Scholar
Waghorn, G. C. & Jones, W. T. (1989). Bloat in cattle. 46. Potential of dock (Rumex obtusifolius) as an antibloat agent for cattle. New Zealand Journal of Agricultural Research 32, 227235.CrossRefGoogle Scholar
Wayne, P. M. & Bazzaz, F. A. (1991). Assessing diversity in plant communities: the importance of within-species variation. Trends in Ecology and Evolution 6, 400404.CrossRefGoogle ScholarPubMed