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Effect of shearing and level of concentrate feeding on the performance of finishing lambs

Published online by Cambridge University Press:  02 September 2010

H. J. Black
Affiliation:
Agricultural Research Institute of Northern Ireland, Hillsborough, Co. Down BT26 6DR
D. M. B. Chestnutt
Affiliation:
Agricultural Research Institute of Northern Ireland, Hillsborough, Co. Down BT26 6DR
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Abstract

The response of finishing Blackface lambs (mean initial live weight 29·6 kg) to shearing and level of concentrate supplementation on a silage-based diet was examined in two experiments. Silage intake decreased as concentrate level increased at mean rate of 0·13 and 0·26 g silage dry matter (DM) per g concentrate DM, in experiments 1 and 2 respectively, with no significant differences between unshorn and shorn lambs. Lambs gained 36, 97, 135, 193 and 224 g/day (s.e. 9·1; P < 0·001) in experiment 1 and 97,133,170,185 and 222 g/day (s.e. 9·9; P < 0·001) in experiment 2 when 0, 200, 400, 600 g/day and concentrate ad libitum were offered respectively. Shearing increased silage DM intake from a mean of 0·50 to 0·56 kg/day (s.e. 0·016; P < 0·05) in experiment 1, and from 0·80 to 0·90 kg/day (s.e. 0·013; P < 0·001) in experiment 2. There was no interaction between shearing and the level of concentrate offered. Despite higher DM intakes by shorn lambs, their live-weight gains were lower than those of unshorn lambs. Gains of unshorn and shorn lambs averaged 153 and 120 g/day (s.e. 5·8; P < 0·001) in experiment 1 and 162 and 161 g/day (s.e. 5·7; P > 0·05) in experiment 2 respectively. This appears to have resulted because shorn lambs could not fully compensate for their increased energy requirements after shearing, by increasing their DM intake. Shearing did not significantly influence carcass characteristics.

It was calculated that with lambs gaining 150 g/day, concentrate requirement was increased from 286 to 335 g/day and total DM intake from 965 to 1107 g/day as a result of shearing.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1992

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References

Agricultural Research Council. 1980. The nutrient requirements of ruminant livestock. Supplement 1. Commonwealth Agricultural Bureaux, Slough.Google Scholar
Armstrong, D. G., Blaxter, K. L., Graham, N. McC. and Wainman, F. W. 1959. The effect of environmental conditions on food utilisation by sheep. Animal Production 1: 112.Google Scholar
Black, H. J. 1990. Effects of shearing and its interaction with plane of nutrition on the performance of housed pregnant ewes and fattening lambs. Ph.D. Thesis, Queen's University Belfast.Google Scholar
Black, J. L. 1983. Growth and development of lambs. In Sheep production (ed. Haresign, W.), pp. 2158. Butterworths, London.Google Scholar
Blaxter, K. L., Graham, N. McC. and Wainman, F. W. 1959. Environmental temperature, energy metabolism and heat regulation in sheep. III. The metabolism and thermal exchanges of sheep with fleeces. Journal of Agricultural Science, Cambridge 52: 4149.CrossRefGoogle Scholar
Bray, A. R., Graafhuis, A. E. and Chrystall, B. B. 1989. The cumulative effect of nutritional, shearing and pre-slaughter washing stresses on the quality of lamb meat. Meat Science 25: 5967.CrossRefGoogle Scholar
Brown, D. C. and Radcliffe, J. C. 1972. Relationship between intake of silage and its chemical composition and in vitro digestibility. Australian journal of Agricultural Research 23: 2533.CrossRefGoogle Scholar
Davey, A. W. F. and Holmes, C. W. 1977. The effects of shearing on the heat production and activity of sheep receiving dried grass or ground hay. Animal Production 24: 355361.Google Scholar
Forbes, J. M., El Shahat, A. A., Jones, R., Duncan, J. G. S. and Boaz, T. G. 1979. The effect of daylength on the growth of lambs. 1. Comparisons of sex, level of feeding, shearing and breed of sire. Animal Production 29: 3342.Google Scholar
Garrett, W. N., Meyer, J. H. and Lofgreen, G. P. 1959. The comparative energy requirements of sheep and cattle for maintenance and gain. Journal of Animal Science 18: 528547.CrossRefGoogle Scholar
Glanville, J. R. D. and Phillips, C. J. C. 1986. The effect of winter shearing Welsh Mountain ewes in the hill environment. Animal Production 42: 455 (abstr.).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
Kirk, J. A., Cooper, R. A. and Chapman, A. 1984. Effect of shearing housed pregnant ewes on their plasma glucose levels, lamb birth weight and lamb growth rate to 56 days. Animal Production 38: 524 (abstr.).Google Scholar
Marai, I. F. M., Nowar, M. S. and Bahgat, L. B. 1987. Effect of docking and shearing on growth and carcass traits of fat-tailed Ossimi sheep. Journal of Agricultural Science, Cambridge 109: 513518.CrossRefGoogle Scholar
Orr, R. J. and Treacher, T. T. 1989. The effect of concentrate level on the intake of grass silage by ewes in late pregnancy. Animal Production 48: 109120.CrossRefGoogle 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
Sykes, A. R. and Slee, J. 1969. Cold exposure of Southdown and Welsh Mountain sheep. 2. Effects of breed, plane of nutrition and previous acclimatization to cold upon skin temperature, heart rate, shivering and respiration rate. Animal Production 11: 7789.Google Scholar
Wilkinson, S. C. 1986. The effect of silage DM and pattern of feeding during pregnancy on the performance of housed breeding ewes. Ph.D. Thesis, Queen's University of Belfast.Google Scholar
Yilala, K. and Bryant, M. J. 1985. The effects upon the intake and performance of store lambs of supplementing grass silage with barley, fish meal and rapeseed meal. Animal Production 40: 111121.Google Scholar