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Effects of pre-mating undernutrition on oestrus, ovulation and prenatal mortality in Merino ewes

Published online by Cambridge University Press:  27 March 2009

A. J. Mackenzie
Affiliation:
Department of Livestock Production, University of New England, Armidale 2351, Australia
T. N. Edey
Affiliation:
Department of Livestock Production, University of New England, Armidale 2351, Australia

Summary

Oestrus, ovulation rate and prenatal mortality were studied in 114 mature Merino ewes of high and low body weight at mating. Three nutritional treatments were imposed over 8 weeks prior to hand mating to fertile rams; high plane (HH), low plane (LL) and 7 weeks of high plane followed by 1 week of fasting immediately prior to mating (HL). Ovarian activity, ovulation rate and the extent and timing of prenatal loss were assessed by the appropriate use of direct ovarian observations, pregnancy diagnosis, returns to service and lambing records.

While both prolonged undernutrition (LL) and acute nutritional restriction (HL) were associated with some suppression of behavioural oestrus, neither had any appreciable effect on ovulation rate or prenatal mortality. In all groups the right ovary was more active in producing ova than the left, and the HH group had more ovarian follicles (≥ 4 mm diameter) than the other two groups. Large unruptured ovarian follicles (6—15 mm diameter) were observed in nine ewes. Significantly more ova shed in multiple ovulations were lost, and multiple-ovulating ewes were more likely to suffer complete rather than partial loss of both embryos. Impaired fertility was evident when ewes that returned to service at an extended cycle length were re-mated.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1975

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References

REFERENCES

Allen, D. M. & Lamming, G. E. (1961). Nutrition and reproduction in the ewe. Journal of Agricultural Science 56, 6979.CrossRefGoogle Scholar
Bennett, D., Nadin, J. B. & Axelsen, A. (1970). The effect of undernutrition during early pregnancy in Merino ewes. Proceedings of the Australian Society of Animal Production 8, 362–5.Google Scholar
Bindon, B. M. (1966). Studies of pituitary ovarian function of the mouse. M.Rur.Sc. Thesis: University of New England, Armidale, Australia.Google Scholar
Braden, A. W. H. & Moule, G. R. (1964). Effects of stress on ovarian morphology and oestrous cycles in ewes. Australian Journal of Agricultural Research, 15, 937–49.CrossRefGoogle Scholar
Casida, L. E. (1963). The level of fertility in the female as influenced by feed level and energy intake. Proceedings of the 6th International Congress of Nutrition 366–75.Google Scholar
Casida, L. E., Woody, C. O. & Pope, A. L. (1966). Inequality in function of the right and left ovaries and uterine horns of the ewe. Journal of Animal Science 25, 1169–71.CrossRefGoogle ScholarPubMed
Coop, I. E. (1966). Effect of flushing-on reproductive performance of ewes. Journal of Agricultural Science 67, 305–24.CrossRefGoogle Scholar
Cumming, I. A. (1972a). The effects of increasing and decreasing liveweight on ovulation and embryonic survival in the Border Leicester x Merino ewe. Proceedings of the Australian Society of Animal Production 9, 192–8.Google Scholar
Cumming, I. A. (1972b). The effect of nutritional restriction on embryonic survival during the first three weeks of pregnancy in the Perendale ewe. Proceedings of the Australian Society of Animal Production 9, 199203.Google Scholar
Edey, T. N. (1966). Nutritional stress and pre-implantation embryonic mortality in Merino sheep. Journal of Agricultural Science 67, 287–93.CrossRefGoogle Scholar
Edey, T. N. (1969). Prenatal mortality in sheep: A review. Animal Breeding Abstracts 37, 173–90.Google Scholar
Edey, T. N. (1970). Nutritional stress and pre-implantation embryonic mortality in Merino sheep (1964–7). General discussion and conclusions. Journal of Agricultural Science 74, 199204.CrossRefGoogle Scholar
Edey, T. N. (1972). Fertility at the first oestrus following embryonic death. Journal of Reproduction and Fertility 28, 147–8.CrossRefGoogle ScholarPubMed
Edey, T. N. & Casida, L. E. (1972). Effects of fasting on oestrus and ovulation in the oestrous rabbit. Australian Journal of Biological Sciences 25, 397403.CrossRefGoogle ScholarPubMed
Edey, T. N., Clark, J. R., First, N. L., Chapman, A. B. & Casida, L. E. (1972). Ovarian response to fasting following high and low planes of nutrition in puberal gilts. Journal of Animal Science 35, 1223–7.CrossRefGoogle ScholarPubMed
Guerra, J. C., Thwaites, C. J. & Edey, T. N. (1972). The effects of components of bodyweight on reproductive efficiency in the Merino ewe. Journal of Agricultural Science 78, 245–9.CrossRefGoogle Scholar
Hafez, E. S. E. (1952). Studies on the breeding season and reproduction of the ewe. Journal of Agricultural Science 42, 189265.CrossRefGoogle Scholar
Killeen, I. D. (1967). The effects of body weight and level of nutrition before, during and after joining on ewe fertility. Australian Journal of Experimental Agriculture and Animal Husbandry 7, 126—36.CrossRefGoogle Scholar
Killeen, I. D. (1972). The effect of live weight on fertilization in maiden and mature Border Leicester x Merino ewes. Proceedings of the Australian Society of Animal Production 9, 186–91.Google Scholar
Lamond, D. R. & Bindon, B. M. (1969). The effect of nutrient intake on ovulation in mice and sheep. Biology of Reproduction 1, 264—71.CrossRefGoogle ScholarPubMed
Lang, D. R. (1964). Ovulations in Merino ewes moved by road or rail in Queensland. Proceedings of the Australian Society of Animal Production 5, 53—7.Google Scholar
McGillivray, J. J., Nalbandov, A. V., Jensen, A. H., Norton, H. W. & Becker, D. E. (1962), Reproductive performance in gilts starved or fed different levels of energy. Journal of Animal Science 21, 1005 (Abstr.).Google Scholar
McInnes, P. & Smith, M. D. (1966). The effect of nutrition before mating on the reproductive performance of Merino ewes. Australian Journal of Experimental Agriculture and Animal Husbandry 6, 455–9.CrossRefGoogle Scholar
MacKenzie, A. J. & Edey, T. N. (1975). Short-term undernutrition and prenatal mortality in young and mature Merino ewes. Journal of Agricultural Science 84, 113–17.CrossRefGoogle Scholar
Marrian, G. F. & Parkes, A. S. (1929). The effect of anterior pituitary preparations administered during dietary anoestrus. Proceedings of the Royal Society Series B 105, 248–57.Google Scholar
O'Shea, T.Piggott, F. A., Thwaites, C. J. & Edey, T. N. (1974). Sperm transport in ewes following embryonic death. Proceedings of the 6th Annual Conference of the Australian Society for Reproductive Biology, Paper No. 23.Google Scholar
Rinaldini, L. M. (1949). Effect of chronic inanition on the gonadotrophic content of the pituitary gland. Journal of Endocrinology 6, 5462.CrossRefGoogle ScholarPubMed
Selye, H. (1950). Stress: the physiology and pathology of exposure to stress. 1st ed.Montreal: Acta Inc.Google Scholar
Smith, I. D. (1962). The effect of plane of nutrition upon the incidence of oestrus in the Merino ewe in Queensland. Australian Veterinary Journal 38, 338–40.CrossRefGoogle Scholar
Smith, I. D. (1964). Reproduction in Merino sheep in tropical Australia. Australian Veterinary Journal 40, 156–60.CrossRefGoogle Scholar
Vanderlinde, R. E. & Westerfield, W. W. (1950). The inactivation of estrone by rats in relation to dietary effects on the liver. Endocrinology 47, 265–73.CrossRefGoogle ScholarPubMed