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Intensifying ewe productivity

Published online by Cambridge University Press:  02 September 2010

J. J. Robinson
J. J. Robinson
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen, AB2 9SB
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Extract

Calculations on the relative efficiencies of cattle, sheep and pigs as meat producers indicate that the main factor limiting the energetic efficiency of sheep meat production is the low average fecundity of the ewe (Blaxter, 1968). Nevertheless with an estimated ‘biological ceiling’ of five lambs per ewe per pregnancy, and a potential mean lambing interval of 6 months (Wilson, 1968), the sheep industry is much further from achieving its biological ceiling than any other form of domestic livestock production. Because these estimates are based on the performance of specific individuals one must question their attainment on a flock basis. Furthermore, even if the necessary technical information were available, its adoption on a commercial scale may be prohibitive on economic grounds. These uncertainties should not deter us from seeking a greater understanding of the basic factors controlling ewe productivity, nor from attempting to integrate this knowledge into existing production systems.

Type
57th Meeting, University of Reading, 10 to 13 September 1973: Report of Meeting on Productivity and Health
Information
Proceedings of the British Society of Animal Production (1972) , Volume 3 , January 1974 , pp. 31 - 40
Copyright
Copyright © British Society of Animal Production 1974

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References

Bichard, M. and Cooper, M. Mcg. 1966. Analysis of production records from a lowland sheep flock. Anim. Prod. 8: 401–410.Google Scholar
Blaxter, K. L. 1968. Efficiencies of farm animals in using crops and by-products in production of foods. Proc. 2nd Wld Conf. Anim. Prod., Maryland, pp. 31–40.Google Scholar
Bradford, G. E., Quirke, J. F. and Hart, R. 1971. Natural and induced ovulation rate of Finnish Landrace and other breeds of sheep. Anim. Prod. 13: 627–635.Google Scholar
Donald, H. P. and Read, J. L. 1967. The performance of Finnish Landrace sheep in Britain. Anim. Prod. 9: 471–476.Google Scholar
Donald, H. P. and Russell, W. S. 1970. The relationship between liveweight of ewe at mating and weight of newborn lamb. Anim. Prod. 12: 273–280.Google Scholar
Ducker, M. J. and Bowman, J. C. 1972. Photoperiodism in the ewe. 5. An attempt to induce sheep of three breeds to lamb every eight months by artificial day-length changes in a non-light-proofed building. Anim. Prod. 14: 323–334.Google Scholar
Gordon, I. 1970. Controlled breeding in sheep—its potential application under Irish fanning conditions. lr. Vet. Journal. 24: 227–241.Google Scholar
Gordon, I. 1971. Induction of early breeding in sheep by standard and modified progestagen-PMS treatments. J. agric. Sci., Camb. 76: 337–341.CrossRefGoogle Scholar
Gunn, R. G., Doney, J. M. and Russel, A. J. F. 1969. Fertility of Scottish Blackface ewes as influenced by nutrition and body condition at mating. J. agric. Sci., Camb. 73: 289–294.Google Scholar
Haffez, E. S. E. 1952. Studies on the breeding season and reproduction of the ewe. J. agric. Sci., Camb. 42: 189–231.Google Scholar
Hendy, C. R. C. and Bowman, J. C. 1971. The effect of the interaction of date of onset of oestrus with the number of previous oestrous periods on lambing percentage. Anim. Prod. 13: 395 (Abstr.).Google Scholar
Hunter, G. L. 1968. Increasing the frequency of pregnancy in sheep. 1. Some factors affecting rebreeding during the post-partum period. Anim. Breed. Abstr. 36: 347–378.Google Scholar
Jennings, J. J. and Crowley, J. P. 1970. The mating of hormone-treated sheep. Anim. Prod. 12: 357 (Abstr.).Google Scholar
Land, R. B. 1973. Genetic improvement of fertility. Rep. Anim. Breed. Res. Orgn. 1973, pp. 7–12.Google Scholar
Land, R. B., Dickinson, A. G. and Read, J. L. 1969. The influence of seasonal variation on fertility and early body growth in sheep. Anim. Prod. 11: 251–257.Google Scholar
Land, R. B. and Mcclelland, T. H. 1971. The performance of Finn-Dorset sheep allowed to mate four times in two years. Anim. Prod. 13: 637–641.Google Scholar
Large, R.V.I 1970. The biological efficiency of meat production in sheep. Anim. Prod. 12: 393–401.Google Scholar
ees, J. L. 1969. The reproductive pattern and performance of sheep. Outl. Agric. 6: 82–88.Google Scholar
Lindsay, D. B. 1973. Metabolic changes induced by pregnancy in the ewe. In Production Disease in Farm Animals (ed. Payne, J. M., Hibbitt, K. G. and Sansom, B. F.), pp. 107–114. Bailliére and Tindall, London.Google Scholar
Mcclelland, T. H. and Quirke, J. F. 1971. Artificial insemination and natural service at a predetermined time in cyclic sheep treated with ‘SC-9880’-Progesterone sponges. Anim. Prod. 13: 323–327.Google Scholar
Meat And Livestock Commission. 1972a. Sheep Improvement, Scientific Study Group Report.Google Scholar
Meat And Livestock Commission. 1972b. Sheep Improvement Services. Records Report No. 4.Google Scholar
Moseley, S. R. and Lamming, G. E. 1969. The induction of breeding activity in lactating sheep by artificial light patterns. Anim. Prod. 11: 284 (Abstr.).Google Scholar
Newton, J. E. and Betts, J. E. 1967. Breeding performance of Dorset Horn ewes augmented by hormonal treatment. Expl Agric. 3: 307–313.Google Scholar
Newton, J. E. Betts, J. E. and Large, R. V. 1970. Increasing litter size in three breeds of sheep by superovulation. J. agric. Sci., Camb. 75: 355–360.Google Scholar
Newton, J. E. and Betts, J. E. 1972. A comparison between the effect of various photoperiods on the reproductive performance of Scottish Half-bred ewes. J. agric. Sci., Camb. 78: 425–433.Google Scholar
Ørskov, E. R., Eraser, C. and Gill, J. C. 1973. A note on the effect of time of weaning and weight at slaughter on feed utilization of intensively fed lambs. Anim. Prod. 16: 311–314.Google Scholar
Owen, J. B. 1969. Sheep production—view of the future. Seale-Hayne Agricultural College. Newton Abbot, Devon.Google Scholar
Purser, A. F. 1973. Variation in date of onset of the breeding season in sheep. Rep. Anim. Breed. Res. Orgn. pp. 24–30.Google Scholar
Robinson, J. J., Fraser, C. and Gill, J. C. 1972. Preliminary observations on the performance of Finnish Landrace × Dorset Horn ewes in an intensive system. Proc. Br. Soc. Anim Prod. p. 134 (Abstr.).Google Scholar
Robinson, T. J. 1967. The control of the ovarian cycle in the sheep. Sydney University Press.Google Scholar
Sharman, G. A. M. 1973. The health of the sheep during investigations into the intensification of sheep production. Vet. Rec. 92: 607–608.Google Scholar
Spedding, C. R. W. 1965. Sheep Production and Grazing Management. Baillière, Tindall and Cox, London.Google Scholar
Tempest, W. M. and Boaz, T. G. 1973. The seasonally of reproductive performance of Merino sheep in Britain. Anim. Prod. 17: 33–41.Google Scholar
Wehnam, G. and Robinson, J. J. 1972. Radiographic pregnancy diagnosis in sheep. J. agric. Sci., Camb. 78: 233–238.Google Scholar
Williams, H. Ll. 1969. An assessment of the role of photo-stimulation in the modification of the breeding season of sheep. Anim. Prod. 11: 283 (Abstr.).Google Scholar
Wilson, P. N. 1968. Biological ceilings and economic efficiencies for the production of animal protein, AD 2000. Chemy. Ind. 899–902.Google Scholar