Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-27T00:30:27.342Z Has data issue: false hasContentIssue false

Effects of fish-meal supplementation and shearing in store/finishing systems for lambs

Published online by Cambridge University Press:  02 September 2010

J. E. Vipond
Affiliation:
Scottish Agricultural College, Edinburgh, West Mains Road, Edinburgh EH9 3JG
J. FitzSimons
Affiliation:
Scottish Agricultural College, Edinburgh, West Mains Road, Edinburgh EH9 3JG
J. Robb
Affiliation:
Scottish Agricultural College, Edinburgh, West Mains Road, Edinburgh EH9 3JG
G. Horgan
Affiliation:
Scottish Agricultural Statistics Service, University of Edinburgh, Edinburgh EH9 3JZ
Get access

Abstract

Development of new systems of lamb finishing for the late winter/spring market involving an extended housed store period on a predominantly straw diet are constrained by unacceptable reduction in muscle mass arising from inadequate protein supply during dietary adaptation from grass to straw. Problems with subsequent finishing on forage brassicas fedin situ arise from carcass contamination due to soiled wool of crossbred lambs which grow long fleeces over the extended store I finishing period. In order to study the effect of fish-meal supplementation on dietary change over from grass to straw 116 Mule wether lambs were allocated to four treatments, three of which received a supplement of 100 glday fish meal for 28 days from housing and introduction of a diet of straw ad libitum and 225 glday grain distillers' dark grains, the fourth group received no fish meal and was unshorn (No F/US). Shearing treatments of shorn (F/S), unshorn (F/US) and crutched (F/C) were applied to fish-meal supplemented group's. After 112 days, the housed lambs were grazed outside on swedes (Brassica napus) and effects of treatments on performance and bacterial contamination of carcasses (shearing treatments only) were studied. Fish-meal supplementation significantly reduced weight loss on dietary change by 2·2 kg after 45 days (P< 0·001). Of fishmeal supplemented lambs 83% eventually ‘finished’ (defined as Meat and Livestock Commission fat class 3LI3H) v. 34% of unsupplemented lambs. Shearing or crutching had little effect on store or finishing performance indicating adequate fleece regrowth for insulation purposes after turn-out. Shorn and crutched lambs had lower levels of bacterial carcass contamination with reductions of 0·06, 0·42 and 0·40 in counts for colony forming units per cm2, coliforms and Escherichia coli on leg sites (P < 0·05). Economic evaluation indicated financial advantage from fish-meal supplementation with an increase in margin over food costs of €3·50 as a result of heavier carcass weight and a reduced need for remedial concentrate feeding in the store period.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 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

Al-Saghier, O. A. S. and Campling, R. C. 1991. Energy and protein supplements to straw-based diets for yearling cattle: effects on straw intake and digestibility. Animal Production 52: 8392.Google Scholar
Dingwall, W. S., Vipond, J. E., Brown, H. E. and Hunter, E. A. 1989. Lamb performance on swedes supplemented with barley or soya-bean meal. Animal Production 48: 634 (abstr.).Google Scholar
Kempster, A. J., Croston, D. and Jones, D. W. 1981. Value of conformation as an indicator of sheep carcass composition within and between breeds. Animal Production 33: 3949.Google Scholar
Kirk, J. A. and Alsop, S. E. 1989. The effect of shearing on housed autumn store lambs. Animal Production 48: 652 (abstr.).Google Scholar
Lawes Agricultural Trust. 1984. Censtat V, mark 4.04. Rothamsted Experimental Station, Harpenden.Google Scholar
Meat and Livestock Commission. 1980. Commercial sheep production yearbook, 1979-80. Economics Livestock and Marketing Services.Google Scholar
Poole, A. H. 1990. The role of forage crops in UK livestock farming. In Meat and milk from forage crops, (ed. G. E. Pollott) British Grassland Society, occasional symposium, no 24. pp. 18.Google Scholar
Russel, A. J. F., Doney, J. M. and Gunn, R. G. 1969. Subjective assessment of body fat in live sheep. Journal of Agricultural Science, Cambridge 72: 451454.CrossRefGoogle Scholar
Salman, A. D. and Owen, E. 1981. A note on the effect of autumn shearing on performance of fattening lambs. Animal Production 33: 337338.Google 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 Agricultural Chemists 46: 829835.Google Scholar
Van Soest, P. J. and 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
Vipond, J. E., Dingwall, W. S., FitzSimons, J. and Hunter, E. A. 1990. Feeding of sheep on brassica root crops. In Meat and milk from forage crops (ed. Pollott, G. E.), Occasional symposium, British Grassland Society, no. 24, pp. 217221.Google Scholar
Vipond, J. E., King, M. E., Ørskov, E. R. and Wetherill, G. Z. 1989. Effects of fish-meal supplementation on performance of overfat lambs fed on barley straw to reduce carcass fatness. Animal Production 48:131138.CrossRefGoogle Scholar