Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-29T16:54:15.533Z Has data issue: false hasContentIssue false

The influence of nutritional level in early pregnancy of the ewe

Published online by Cambridge University Press:  27 March 2009

I. E. Coop
Affiliation:
Lincoln College, Canterbury, New Zealand
V. R. Clark
Affiliation:
Lincoln College, Canterbury, New Zealand

Summary

A series of three large-scale field trials, involving 3500 ewes over a 3-year-period, was conducted to study the effect of restricted nutrition of breeding ewes in early pregnancy. Control or non-restricted ewes were fed at approximately maintenance level and restricted ewes at approximately half-maintenance. The majority of ewes fell into two categories—those 2–3 weeks pregnant at the time restriction was commenced and those 5–7 weeks pregnant. Restriction was applied for from 5 to 8 weeks, live-weight differences of approximately 10 1b were achieved.

Differences in performance in individual trials were invariably very small, and nonsignificant. The main effect of restricted nutrition over all trials was to decrease twinning by 0·5% and decrease the number of barren ewes by 0·8%. These differences are considered to be negligible. Only one statistically significant effect was observed within one of the trials—this was a depression in twinning in ewes 18–24 days pregnant at the time of applying the treatment, but this effect could not be confirmed in the other two trials. However, the fleece grown was affected by treatment—the fleece weight being depressed by approximately ½ lb, and grade reduced slightly.

It is concluded that restricted nutrition at the level and time applied has no effect on reproductive performances of ewes and therefore the practice of restriction in early pregnancy to conserve feed for late pregnancy is a sound policy.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1969

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

REFERENCES

Bennett, D., Axelsen, A. & Chapman, H. W. (1964). The effect of nutritional restriction during early pregnancy on numbers of lambs born. Proc. Aust. Soc. Anim. Prod. 5, 70–2.Google Scholar
Coop, I. E. (1966a). The response of ewes to flushing. Wld Rev. Anim. Prod. 4, 6976.Google Scholar
Coop, I. E. (1966b). Effect of flushing on reproductive performance of ewes. J. agric. Sci., Camb. 67, 306–23.CrossRefGoogle Scholar
Coop, I. E. & Clark, V. R. (1960). The reproductive performance of ewes mated on lucerne. N.Z. Jl agric. Res. 3, 922–33.Google Scholar
Dutt, R. H. (1954). Fertility rate and embryonic death loss in ewes early in the breeding season. J. Anim. Sci. 13, 464–73.CrossRefGoogle Scholar
Edey, T. N. (1966). Nutritional stress and pre-implantation embryonic mortality in Merino sheep. J. agric. Sci., Camb., 67, 287–93.Google Scholar
El Sheik, A. S., Hulet, C. V., Pope, A. L. & Casida, L. E. (1955). The effect of level of feeding on the reproductive capacity of the ewe. J. Anim. Sci. 14, 919–29.CrossRefGoogle Scholar
Hodge, R. W. (1966). The effect of nutritional restriction during early and mid pregnancy on the reproductive performance of crossbred ewes. Aust. J. exp. Agric. Anim. Husb. 6, 311–3.CrossRefGoogle Scholar
Hulet, C. V., Price, D. A. & Foote, W. C. (1968). Effects of variation in light, month of year and nutrient intake on reproductive phenomenon in ewes during the breeding season. J. Anim. Sci. 27, 684–90.CrossRefGoogle Scholar
Hulet, C. V., Voigtlander, H. P. Jr, Pope, A. L. & Casida, L. E. (1956). The nature of early season infertility in sheep. J. Anim. Sci. 15, 607–16.CrossRefGoogle Scholar
Laffey, N. & Hart, D. S. (1959). Embryonic loss from late breeding season matings. N.Z. Jl agric. Res. 2, 1159–66.CrossRefGoogle Scholar
Quinlivan, T. D., Martin, C. A., Taylor, B. W. & Cairney, I. M. (1966). Estimates of pre- and perinatal mortality in the New Zealand Romney Marsh ewe. J. Reprod. Fert. 11, 379.Google Scholar
Robinson, T. J. (1957). Prog, in the Physiol. of Farm Animals (ed. Hammond, J.), vol. III. London: Butterworths.Google Scholar
Tassell, R. (1967). The effects of diet on reproduction in pigs, sheep and cattle. I. Pigs. Br. vet. J. 123, 7684.Google Scholar