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Lamb and milk production of a flock of dairy ewes under an accelerated breeding regime

Published online by Cambridge University Press:  27 March 2009

E. Eyal ,
A. Lawi ,
Y. Folman  and
M. Morag
E. Eyal
Affiliation:
Division of Dairy and Mullon Sheep, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
A. Lawi
Affiliation:
Division of Dairy and Mullon Sheep, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
Y. Folman
Affiliation:
Division of Dairy and Mullon Sheep, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
M. Morag
Affiliation:
Division of Dairy and Mullon Sheep, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
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Summary

The management of an experimental flock of dairy sheep was changed from a onceyearly to a frequent-lambing regime. Results are reported on the performance of the flock under the new regime in the course of 3 years. There were 53 and 160, 46 and 242, and 70 and 237 Awassi and Assaf (East-Friesian x Awassi) ewes, respectively, in the flock at the beginning of the 3 consecutive years. A breeding calendar was adopted to produce four mating seasons each year, namely June–July; September–October; December–January; March–April.

Average annual production was 1·16 ± 0·24 lambs and 209±9 kg milk for Awassi ewes, and 2·07 ± 0·20 lambs and 287 ± 19 kg milk for Assaf ewes. Hoggets of the same breeds produced 0·61 ± 0·14 and 1·23 ± 0·10 lambs and 99 ± 37 and 220 ± 21 kg of milk, respectively.

Following the February-March lambing, conception rates of hormone-treated ewes weaned 2 or 70 days post-partum were 57·1 and 48·8% respectively (P < 0·10). There were no differences in the length of the post-partum interval to conception between low and high milk-yielding ewes. Fertility was highest in the September–October and December–January mating periods, intermediate in June–July and lowest in March–April.

Twenty-seven per cent of the original 126 mature Assaf ewes and 15% of the original 46 mature Awassis remained in the flock at the end of 3 years for further breeding. Thirty-one per cent of the mature Assaf population (mixed ages) and 21% of the hoggets were culled in the course of 3 years due to failure to conceive within 6 months post-partum. With Awassi ewes the rate of failure was much higher.

Ewes which had lambed twice and completed, on average, 1·5 lactations in a year, produced 30% more milk per year than those which lambed only once during the same period. The more frequent lambing resulted in shorter lactations (156 days) and lower average daily milk yields (1·27 kg) compared with the 182 days and 1·41 kg in the less frequently lambing groups. Pregnancy during early stages of lactation had a small but significant (P < 0·05) effect on the concurrent lactation. Shortening the breeding interval had a much more marked effect on the subsequent lactation. Ewes that conceived, on average, 120 days post-partum, in the subsequent lactations produced 17% more milk than those conceiving 60 days post-partum (P <0·02).

Ewes gaining weight at a rate of 5–7 kg during the first 2 months of pregnancy produced, on average, 0·27 kg less milk per day than those which either lost or maintained their weight in that period (P < 0·01).

Type
Research Article
Information
The Journal of Agricultural Science , Volume 91 , Issue 1 , August 1978 , pp. 69 - 79
Copyright
Copyright © Cambridge University Press 1978

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References

Alef, B. (1971). Additional lambing and summer lambing in dairy ewes. Publication, Extension Service, Ministry of Agriculture, Tel Aviv, Israel. (In Hebrew).Google Scholar
Alef, B. (1973). Frequent lambing in dairy ewes. Publication, Extension Service, Ministry of Agriculture, Tel Aviv, Israel. (In Hebrew.)Google Scholar
Amir, D. & Volcani, R. (1965). The sexual season of the Awassi fat-tailed ewe. Journal of Agricultural Science, Cambridge 64, 83–85.CrossRefGoogle Scholar
Belschner, H. G. (1961). Sheep Management and Diseases, p. 91. Sydney: Pty, Ltd. Angus and Robertson.Google Scholar
Copenhaver, J. S. & Carter, R. C. (1964). Maximizing ewe productivity by very early weaning and rebreeding. Journal of Animal Science 23, 302. (Abstr.)Google Scholar
Coppock, C. E., Everett, R. W., Natzke, R. P. & Ainslie, H. R. (1974). Effect of dry period length on Holstein milk production and selected disorders at parturition. Journal of Dairy Science 57, 712–718.CrossRefGoogle Scholar
Ducker, M. J. & Bowman, J. C. (1972). Photoperiodism in the ewe. 5. An attempt to induce sheep of three breeds to lamb every eight months by artificial daylight changes in a non-light-proofed building. Animal Production 14, 323–334.Google Scholar
Eyal, E., Folman, Y. & Morag, M. (1973). Lamb production in frequently lambing dairy sheep World Review of Animal Production 9, 64–69.Google Scholar
Eyal, E. & Goot, H. (1968). Vital statistics and milk and lamb production of Ft1 ewes (Awassi x East Friesian) under farm conditions. Pamphlet, Volcani Institute Agricultural Research, Bet Dagan Israel 124, 1–24. (Hebrew, with English summary.)Google Scholar
Finci, M. (1957). The improvement of the Awassi breed of sheep in Israel. Bulletin Research Council, Israel 68, 1–106.Google Scholar
Folman, Y., Volcani, R. & Eyal, E. (1966). Motheroffspring relationships in Awassi sheep. 1. The effect of different suckling regimes and time of weaning on the lactation curve and milk yield in dairy flocks. Journal of Agricultural Science, Cambridge 67, 359–368.CrossRefGoogle Scholar
Goot, H. (1965). Studies on the native Awassi sheep and its crosses with exotic East-Friesian milk sheep. Ph.D. thesis, The Hebrew University of Jerusalem, Israel.Google Scholar
Gordon, J. G. & Tribe, D. E. (1951). The self-selection of diet by pregnant ewes. Journal of Agricultural Science, Cambridge, 41, 187–190.CrossRefGoogle Scholar
Gould, M. B. and Whiteman, J. W. (1973). Postpartum reproductive performance of early weaned spring lambing ewes. Journal of Animal Science 36, 1041–1043.CrossRefGoogle ScholarPubMed
Hunter, G. L. & Van Aarde, I. M. R. (1973). Influence of season of lambing on post-partum intervals to ovulation and oestrus in lactating and dry ewes at different nutritional levels. Journal of Reproduction and Fertility 32, 1–8.CrossRefGoogle ScholarPubMed
Land, R. B. (1974). Physiological studies and genetic selection for sheep fertility. Animal Breeding Abstracts 42, 155–158. (A review.)Google Scholar
Land, R. B. & Mcllelland, T. H. (1971). The performance of Finn-Dorset sheep allowed to mate four times in two years. Animal Production 13, 637–641.Google Scholar
Morag, M., Degen, A. A. & Popliker, F. (1973). The reproductive performance of German Mutton Merino ewes in a hot arid climate. Zeitschrift Tierzuchtung Zuchtungs Biologie 89, 340–345.CrossRefGoogle Scholar
Morag, M. & Eyal, E. (1971). Post-partum conception in lactating Awassi and East-Friesian x Awassi dairy ewes. Journal of Agricultural Science, Cambridge 77, 109–116.CrossRefGoogle Scholar
Morag, M., Sagi, R., Eyal, E. & Folman, Y. (1973). The definition of milk yield and milk fractions in lactating animals. Journal of Agricultural Science, Cambridge 81, 361–363.CrossRefGoogle Scholar
Peart, J. N. (1968). Some effects of liveweight and body condition on the milk production of Blackface ewes. Journal of Agricultural Science, Cambridge 70, 331–338.CrossRefGoogle Scholar
Reid, R. L. & Hinks, N. T. (1962). Feed requirements and voluntary feed intake in late pregnancy. Australian Journal of Agricultural Research 13, 1092–1111.CrossRefGoogle Scholar
Robinson, J. J. (1974). Intensifying ewe productivity. Proceedings of the British Society of Animal Production 3, 31–40.Google Scholar
Rottensten, K. & Franklin, A. (1971). Studies on Awassi sheep in Lebanon. II. Reproduction of a flock bred at four month intervals. Journal of Agricultural Science, Cambridge 77, 375–377.CrossRefGoogle Scholar
Smith, A., Wheelock, J. V. & Dodd, F. H. (1967). The effect of milking throughout pregnancy on milk secretion in the succeeding lactation. Journal of Dairy Research 34, 145–150.CrossRefGoogle Scholar
Stern, D. (1973). Effects of different nutritional regimes during pregnancy on some metabolic responses of dairy ewes before and after parturition. Ph.D. thesis. The Hebrew University of Jerusalem, Israel. (Hebrew, with English Summary.)Google Scholar
Swanson, E. W. (1965). Comparing continuous milking with sixty-day dry periods in successive Lactations. Journal of Dairy Science 48, 1205–1209.CrossRefGoogle ScholarPubMed
Tohamitchian, L., Ricordeau, G., Lefevre, C. & Desvingues, A. (1973 a). Observations surl'anoestrus post-partum de brebis Romanov apres un agnelage en saison sexyalle. Annales de Zootechnie 22, 265–301.Google Scholar
Tchamitchian, L., Ricordeau, G., Lefèvre, C. & Desvingues, A. (1973 b). Performances des brebis Romanov soumises à un rythme accéleré de reproduction. Annales Zootechnie, 22, 303–310.CrossRefGoogle Scholar