Hostname: page-component-8448b6f56d-gtxcr Total loading time: 0 Render date: 2024-04-20T01:54:01.268Z Has data issue: false hasContentIssue false
  • English
  • Français

The effect of season and the introduction of rams on oestrous activity in Somali, Nandi, Merino, Karakul and New Zealand Romney Marsh ewes in Kenya

Published online by Cambridge University Press:  02 September 2010

A. B. Carles  and
W. A. K. Kipngeno
A. B. Carles
Affiliation:
Department of Animal Production, University of Nairobi, PO Box 29053, Kabete, Kenya
W. A. K. Kipngeno
Affiliation:
Department of Animal Production, University of Nairobi, PO Box 29053, Kabete, Kenya
Get access

Abstract

A study was made of the levels of oestrous activity of two indigenous breeds of sheep (Somali and Nandi) and three exotic breeds of sheep (Merino, Karakul and New Zealand Romney Marsh) over a period of 3 years, in an equatorial environment. Breed was the only significant source of variation for the length of the oestrous cycle (P < 0·01). The mean lengths of the oestrous cycle were 17·2 (s.d. 3·21), 17·5 (s.d. 2·24), 17·9 (s.d. 2·99), 17·5 (s.d. 2·57) and 16·5 (s.d. 3·41) days for the Somali, Nandi, Merino, Karakul and Romney Marsh breeds, respectively.

The mean percentage of ewes of the different breeds showing oestrus in 20-day periods were 69·8 (s.d. 22·57), 49·9 (s.d. 18·67), 63·4 (s.d. 25·70), 79·2 (s.d. 20·30) and 33·2 (s.d. 23·50) % for the Somali, Nandi, Merino, Karakul and Romney Marsh breeds, respectively. Time-series analysis did not detect any evidence of seasonal variation in oestrous activity, although there was an indication that the Merino and Romney Marsh breeds showed a marked increase in oestrous activity following, the introduction of rams. It was concluded that the variation in level of oestrous activity was short term and random.

Type
Research Article
Information
Animal Production , Volume 43 , Issue 3 , December 1986 , pp. 447 - 457
Copyright
Copyright © British Society of Animal Science 1986

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

Anderson, J. 1941. Further invesigations on artificial insemination of sheep. Journal of Agricultural Science, Cambridge 31: 354–369.CrossRefGoogle Scholar
Anderson, J. 1972. The oestrous cycle in Merino, Masai and Somali sheep. Zootecnica e Veterinaria 27: 77–94.Google Scholar
Blackman, R. B. and Tukey, J. W. 1958. The measurement of power spectrum from the point of view of communication engineering. Bell Systems Technical Journal 37: 485–569.CrossRefGoogle Scholar
Box, G. E. P. and Jenkins, G. M. 1968. Some recent advances in forecasting and control. Applied Statistics 17: 19–109.Google Scholar
Box, G. E. P. and Jenkins, G. M. 1970. Time Series Analysis: Forecasting and Control, pp. 39–50. Holden Day, San Francisco.Google Scholar
Carles, A. B. 1986. The levels of, and constraints to, productivity of goats and sheep at Ngurunit and Korr in Marsabit District, Kenya. In: Integrated Project in Arid Lands, Technical Report Series E7. UNESCO, Nairobi. In press.Google Scholar
Chatfield, C. 1974. The Analysis of Time Series — Theory and Practice, pp. 15–20. Chapman and Hall, London.Google Scholar
Dixon, W. J. 1944. Further contribution to the theory of serial correlation. Annals of Mathematical Statistics 15: 119.CrossRefGoogle Scholar
El Wishy, A. B., El Sawaf, S. A. and Fouad, K. 1976. Some aspects of reproduction in fat-tailed sheep in the subtropics. II. Seasonal variation in ovarian activity. Zeitschrift fü Tierzuchtung und Ziichtungsbiologie 93: 121–134.CrossRefGoogle ScholarPubMed
Gaillard, Y. 1979. [Reproductive characteristics of the Uda ewe.] Revue d'Élevage et de Medecine Véterinaire des Pays Tropicaux 32: 285–290.Google Scholar
Granger, C. W. J. and Hatanaka, M. 1964. Spectra Analysis of Economic Time Series, pp. 61. Princeton University Press, Princeton.Google Scholar
Hafez, E. S. E. 1952a. Studies on the breeding season and reproduction of the ewe. Pt I. The breeding season in different environments. Pt II. The breeding season in one locality. Journal of Agricultural Science, Cambridge 42: 189–231.Google Scholar
Hafez, E. S. E. 1952b. Studies on the breeding season and reproduction of the ewe. Pt IV. Studies on the reproduction of the ewe. Journal of Agricultural Science, Cambridge 42: 241–255.Google Scholar
Hafez, E. S. E. 1953. Ovarian activity in Egyptian (fat-tailed) sheep. Bulletin, Cairo University, Faculty of Agriculture, No. 34.Google Scholar
Hunter, G. L. 1959. A contribution to the study of the problem of low fertility among Merino ewes in South Africa. Journal of Agricultural Science, Cambridge 52: 282–295.CrossRefGoogle Scholar
Lyle, A. D. and Hunter, G. L. 1967. The effects of ram introduction during spring, summer and autumn on the incidence of oestrus in three Merino breeding flocks in East Griqualand. Proceedings of the South African Society of Animal Production 6: 202–207.Google Scholar
Mason, I. L. and Maule, J. P. 1960. The indigenous livestock of Eastern and Southern Africa. Technical Communication, Bureau of Animal Breeding and Genetics, No. 14, pp. 95, 105. Commonwealth Agricultural Bureaux, Slough.Google Scholar
Otieno, J. A. M. 1975. On time series analysis, pp. 37–38. M.Sc. Thesis, University of Nairobi.Google Scholar
Radford, H. M. and Watson, R. H. 1957. Influence of rams on ovarian activity and oestrus in Merino ewes in the spring and early summer. Australian Journal of Agricultural Research 8: 460–470.Google Scholar
Radford, H. M., Watson, R. H. and Wood, G. F. 1960. A crayon and associated harness for the detection of mating under field conditions. Australian Veterinary Journal 36: 57–66.CrossRefGoogle Scholar
Rao, C. K. 1966. Studies on reproduction in Indian breeds of sheep — Bannur and Nilgiri breeds. Indian Veterinary Journal 43: 130–133.Google ScholarPubMed
Riches, J. H. and Watson, R. H. 1954. The influence of the introduction of rams on the incidence of oestrus in Merino ewes. Australian Journal of Agricultural Research 5: 141–147.Google Scholar
Sahni, K. L. AND Roy, A. 1972. A comparative study on the reproductive performance of certain native (Bikaneri, Mandia), exotic (Romney Marsh, Corriedale) and half-bred (Corriedale · Bikaneri) breeds of sheep under tropical conditions. Indian Journal of Animal Science 42: 819–823.Google Scholar
Sahni, K. L., Tiwari, S. B. and Sahni, M. S. 1976. Effect of season on the occurrence of oestrus and fertility in different breeds of sheep under semi-arid conditions. Indian Veterinary Journal 53: 515–522.Google ScholarPubMed
Saraswat, K. C., Seth, O. N. and Roy, A. 1968. Effect of season on fertility in an experimental flock of Bikaneri (Magra) sheep and live-weight gain of lambs. Indian Journal of Veterinary Science 38: 778–784.Google Scholar
Schinckel, P. G. 1954. The effect of the ram on the incidence and occurrence of oestrus in ewes. Australian Veterinary Journal 30: 189–195.CrossRefGoogle Scholar
Stewart, A. M. and Mom, R. J. 1943. Fertility in Merino sheep in North-Western Australia. I. Observations on the incidence of oestrus in Merino ewes at Warralong Station. Australian Veterinary Journal 19: 152–164.Google Scholar
Symington, R. B. and Oliver, J. 1966. Observations on the reproductive activity of tropical sheep in relation to the photoperiod. Journal of Agricultural Science, Cambridge 67: 7–12.CrossRefGoogle Scholar
Taparia, A. L. 1972. Breeding behaviour in Sonadi sheep. Indian Journal of Animal Science 42: 576–579.Google Scholar
Tukey, J. W. 1950. The sampling theory of power spectrum estimates. Proceedings of Symposium on Application of the Autocorrelation Analysis to Physical Problems, p. 735. Office of Naval Research, Washington, DC.Google Scholar
Underwood, E. J. and Shier, F. L. 1952. The incidence of oestrus in ewes grazing on subterranean-clover pastures.Australian Veterinary Journal 28: 157–158.Google Scholar
Watson, R. H. and Radford, H. M. 1960. The influence of rams on onset of oestrus in Merino ewes in the spring. Australian Journal of Agricultural Research 11: 65–71.CrossRefGoogle Scholar
WORLD METEOROLOGICAL ORGANISATION. 1966. Climatic change: report of a working group of the Commission for Climatology. Technical Note, World Meteorological Organisation, No. 79, pp. 33–46.Google Scholar
Yeates, N. T. M. 1949. The breeding season of the sheep with particular reference to its modification by artificial means using light. Journal of Agricultural Science, Cambridge 39: 1–43.CrossRefGoogle Scholar
Yeates, N. T. M. 1956. The effect of light on the breeding season, gestation, and birth weight of Merino sheep. Australian Journal of Agricultural Research 7: 440–446.Google Scholar
Yenikoye, A. 1984. [Annual variations in oestrous behaviour, ovulation rate and ovulatory potential of Pulani ewes in Niger.] Reproduction, Nutrition, Développement 24: 11–19.Google Scholar