Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-12-03T20:46:46.775Z Has data issue: false hasContentIssue false

Some consequences of imposing different continuous grazing pressures in the spring on sward morphology, herbage quality and the performance of young beef cattle

Published online by Cambridge University Press:  27 March 2009

J. R. B. Tallowin
Affiliation:
The Animal and Grassland Research Institute, Hurley, Maidenhead, Berkshire, SL6 5LR
J. H. H. Williams
Affiliation:
The Animal and Grassland Research Institute, Hurley, Maidenhead, Berkshire, SL6 5LR
R. V. Large
Affiliation:
The Animal and Grassland Research Institute, Hurley, Maidenhead, Berkshire, SL6 5LR

Summary

The effects of different severities of continuous grazing imposed during the spring followed by a uniform continuous grazing management from midsummer onwards were examined in relation to sward morphology, herbage quality and the performance of young beef cattle in the years 1980 and 1981. The three grazing severities were based upon maintaining a constant sward height, namely 35 mm (severe), 50 mm (moderate) and 75 mm (lenient). From 1 June onwards a uniform grazing severity with a sward height of 60 mm was imposed. The grazing pressure on each paddock was adjusted by either adding or removing of cattle to maintain the target sward heights. When the grazing pressure was changed in June, the digestibility of both the herbage components on offer and the total herbage selected by the cattle was higher in the swards that had been severely grazed than that in the leniently grazed treatments. This appeared to be due to the combination of a higher proportion of younger, more digestible leaf laminae, less dead and less maturing true stem being present in the swards that had previously been severely grazed. Over the season as a whole, there was no significant difference between the grazing treatments in terms of individual animal performance or overall animal live-weight production per hectare.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1986

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

Anon. (1976). The Grassmeter. Report of the Breeding and Production Organisation, 1975/6, Milk Marketing Board, Thames Ditton, Surrey, No. 26.Google Scholar
Bircham, J. S. & Hodgson, J. (1983). The influence of sward conditions on rates of herbage growth and senescence in mixed swards under continuous stocking management. Grass and Forage Science 38, 323331.CrossRefGoogle Scholar
Castle, M. E. & Watson, J. N. (1978). A comparison of continuous grazing systems for milk production. Journal of the British Grassland Society 33, 123129.CrossRefGoogle Scholar
Ernst, P., Le Du, Y. L. P. & Carlier, L. (1980). Animal and sward production under rotational and continuous grazing management – a critical appraisal. Proceedings of an International Symposium, The Role of Nitrogen in Intensive Grassland Production, Wageningen, 1980, pp. 119126.Google Scholar
Grant, S. A., Barthram, G. T., Torvell, L., King, J. & Smith, H. K. (1983). Sward management, lamina turnover and tiller population density in continuously-stocked Lolium perenne-dominated swards. Grass and Forage Science 38, 333344.CrossRefGoogle Scholar
Holmes, C. W. (1974). The Massey grassmeter. Dairy-farming Annual, pp. 2630.Google Scholar
Le Du, Y. L. P., Baker, R. D. & Newberry, R. D. (1981). Herbage intake and milk production by grazing dairy cows. 3. The effect of grazing severity under continuous-stocking. Grass and Forage Science 36, 307318.CrossRefGoogle Scholar
McKeekan, C. P. & Walshe, K. J. (1963). The interrelationships of grazing method and stocking rate in the efficiency of pasture utilization by dairy cattle. Journal of Agricultural Science, Cambridge 61, 147166.CrossRefGoogle Scholar
Michell, P. & Large, R. V. (1983). The estimation of herbage mass of perennial ryegrass swards: a comparative evaluation of a rising-plate meter and a single probe capacitance meter calibrated at and above ground level. Grass and Forage Science 38, 195199.CrossRefGoogle Scholar
Morris, R. M. (1969). The pattern of grazing in ‘continuously’ grazed swards. Journal of the British Grassland Society 24, 6670.CrossRefGoogle Scholar
Parsons, A. J., Leafe, E. L., Collett, B., Penning, P. D. &, Lewis, J. (1983). The physiology of grass production under grazing. II. Photosynthesis, crop growth and animal intake of continuously-grazed swards. Journal of Applied Ecology 20, 127139.CrossRefGoogle Scholar
Parsons, A. J., Leafe, E. L., Collett, B. & Stiles, W. (1983). The physiology of grass production under grazing. I. Characteristics of leaf canopy photosynthesis of continuously-grazed swards. Journal of Applied Ecology 20, 117126.CrossRefGoogle Scholar
Terry, R. A. & Tilley, J. M. A. (1964). The digestibility of the leaves and stems of perennial ryegrass, cocksfoot, timothy, tall fescue, lucerne and sainfoin, as measured by an in vitro procedure. Journal of the British Grassland Society 19, 363372.CrossRefGoogle Scholar
Tilley, J. M. & Terry, R. A. (1963). A two-stage technique for in vitro digestion of forage crops. Journal of the British Grassland Society 18, 104111.CrossRefGoogle Scholar