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The effect of different durations and times of high- level feeding prior to mating on the reproductive performance of Scottish Blackface ewes

Published online by Cambridge University Press:  02 September 2010

R. G. Gunn
Affiliation:
Hill Farming Research Organisation, Bush Estate, Penicuik, Midlothian EH26 0PY
J. M. Doney
Affiliation:
Hill Farming Research Organisation, Bush Estate, Penicuik, Midlothian EH26 0PY
W. F. Smith
Affiliation:
Hill Farming Research Organisation, Bush Estate, Penicuik, Midlothian EH26 0PY
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Abstract

One hundred and sixty-four Scottish Blackface ewes from two different farm sources were brought into a uniform moderately-poor level of body condition by early November. Five groups of approximately 33 ewes were then fed different amounts of pelleted dried grass and hay on pasture to achieve either high (H) or live-weight maintenance (M) levels of intake for different durations and at different times in the 36 days prior to mating at a synchronized oestrus. One group of ewes was fed the M level throughout, two groups were fed the H level for 18 days either preceded or followed by 18 days of the M level and two groups were fed the H level for 27 days either preceded or followed by 9 days of the M level. After mating, all ewes were fed the M level until slaughtered on return to service or at 28 (± 8) days after mating for counts of corpora lutea and viable embryos relating to first mating.

The gain in body condition and live weight after 18 days of H feeding was about half that achieved after 27 days. Time of H feeding had no differential effect on gain in condition or live weight. H feeding increased ovulation rate only if fed immediately prior to mating. When a period of M feeding preceded mating, most of the advantage was lost, particularly with 18 days of M feeding after 18 days of H feeding. Embryo mortality measured as ova loss was not significantly affected by either the duration or time of H feeding, although there was a trend for loss to decrease with increasing duration. Potential lambing rate to first mating was therefore significantly increased by H feeding for 27 days even when followed by 9 days of M feeding prior to mating but was not significantly increased by H feeding for only 18 days even when fed immediately prior to mating.

Differences in response were obtained from the ewes from the two sources. H feeding only produced a significant improvement in reproductive performance when potential was high and this was partly related to greater size. In populations with low potential, the provision of H feeding in the pre-mating period is therefore of doubtful economic advantage.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1984

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References

REFERENCES

Allen, D. M. and Lamming, G. E. 1961. Nutrition and reproduction in the ewe. J. agric. Sci., Camb. 56: 6979.Google Scholar
Coop, I. E. 1966. Effect of flushing on reproductive performance of ewes. J. agric. Sci., Camb. 67: 305323.Google Scholar
Edey, T. N. 1967. Early embryonic death and subsequent cycle length in the ewe. J. Reprod. Fert. 13: 437443.Google Scholar
Gunn, R. G. 1977. The effects of two nutritional environments from 6 weeks prepartum to 12 months of age on lifetime performance and reproductive potential of Scottish Blackface ewes in two adult environments. Anim. Prod. 25: 155164.Google Scholar
Gunn, R. G. and Doney, J. M. 1973. A note on the influence of pattern of live-weight and body condition recovery between weaning and mating on food consumption and reproductive performance of Scottish Blackface ewes. J. agric. Sci., Camb. 81: 189191.Google Scholar
Gunn, R. G. and Doney, J. M. 1975. The interaction of nutrition and body condition at mating on ovulation rate and early embryo mortality in Scottish Blackface ewes. J. agric. Sci., Camb. 85: 465470.Google Scholar
Gunn, R. G. and Doney, J. M. 1979. Fertility in Cheviot ewes. 1. The effect of body condition at mating on ovulation rate and early embryo mortality in North and South Country Cheviot ewes. Anim. Prod. 29: 1116.Google Scholar
Gunn, R. G., Doney, J. M. and Russel, A. J. F. 1969. Fertility in Scottish Blackface ewes as influenced by nutrition and body condition at mating. J. agric. Sci., Camb. 73: 289294.Google Scholar
Gunn, R. G., Doney, J. M. and Russel, A. J. F. 1972. Embryo mortality in Scottish Blackface ewes as influenced by body condition at mating and by postmating nutrition. J. agric. Sci., Camb. 79: 1925.Google Scholar
Gunn, R. G., Doney, J. M. and Smith, W. F. 1979. Fertility in Cheviot ewes. 2. The effect of level of pre-mating nutrition on ovulation rate and early embryo mortality in North and South Country Cheviot ewes in moderately good condition at mating. Anim. Prod. 29: 1723.Google Scholar
Hulet, C. V., Blackwell, R. L., Ercanbrack, S. K., Price, D. A. and Humphrey, R. D. 1962. Effects of feed and length of flushing period on lamb production in range ewes. J. Anim. Sci. 21: 505510.Google Scholar
Killeen, I. D. 1967. The effects of body weight and level of nutrition before, during and after joining on ewe fertility. Aust. J. exp. Agric. Anim. Husb. 7: 126136.Google Scholar
Wallace, L. R. 1953. Management of the fat lamb flock. N.Z. Jl. Agric. 87: 529535.Google Scholar