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Evaluation of the efficiency of alternative selection schemes and breeding objectives in dairy sheep of Greece

Published online by Cambridge University Press:  02 September 2010

A. Kominakis ,
G. Nitter ,
D. Fewson  and
E. Rogdakis
A. Kominakis
Affiliation:
Institute of Animal Breeding and Husbandry, Agricultural University of Athens, Athens, Greece
G. Nitter
Affiliation:
Institute of Animal Breeding and Husbandry, University of Hohenheim, Stuttgart, Germany
D. Fewson
Affiliation:
Institute of Animal Breeding and Husbandry, University of Hohenheim, Stuttgart, Germany
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Abstract

The genetic and economic efficiency of alternative selection schemes and breeding objectives for the Karagouniki dairy sheep in Greece was investigated by model calculations. Criteria of efficiency were the annual genetic gain for the aggregate breeding value, the profit per ewe in the population and the annual selection responses for single traits. The introduction of a two-tier selection scheme, where the recorded ewes are separated into a nucleus and a pre-nucleus, was found superior in both genetic and economic terms for a breeding objective comprising the traits milk yield and number of lambs weaned per ewe per annum. Highest rates for annual genetic gain and selection responses were obtained when the nucleus size was proportionately 0·05 of the population (200 000 ewes), the size of the test matings 0·50 to 0·60 of the size of the pre-nucleus unit (0·10 of the population) and the number of daughters per test ram 40. Opening the nucleus to replacement ewes from the lower tier did not affect positively the annual genetic gain and the selection responses. Furthermore, a breeding objective comprising the traits fat yield and number of lambs weaned per ewe and per annum was found very efficient in both genetic and economic terms while selection on growth and carcass traits did not seem to be justified.

Keywords

breeding programmesdairyingGreeceselection programmesheep
Type
Research Article
Information
Animal Science , Volume 64 , Issue 3 , June 1997 , pp. 453 - 461
Copyright
Copyright © British Society of Animal Science 1997

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References

Atkins, K. D. and Thompson, R. 1986a. Predicted and realized responses to selection for an index of bone length and body weight in Scottish Blackface sheep. 1. Responses in the index and component traits. Animal Production 43: 421–435.Google Scholar
Atkins, K. D. and Thompson, R. 1986b. Predicted and realized responses to selection for an index of bone length and body weight in Scottish Blackface sheep. 2. Correlated responses in lifetime productivity. Animal Production 43: 437–445.Google Scholar
Barillet, F. and Boichard, D. 1987. Studies on dairy production of milking ewes. I. Estimates of genetic parameters for total milk composition and yield. Genetics, Selection, Evolution 19: 459–474.CrossRefGoogle Scholar
Barillet, F., Elsen, J. M. and Roussely, M. 1986. Optimization of a selection scheme for milk composition and yield in milking ewes: example of the Lacaune breed. Proceedings of the third world congress on genetics applied to livestock production, Lincoln, vol. 9, pp. 658–663.Google Scholar
Barillet, F., Elsen, J. M., Roussely, M., Belloc, J. P., Brios, M., Casu, S., Carta, R. and Poievy, J. P. 1988. Selection lait-viande en brebis laitieres. Proceedings of the third world congress on sheep and beef cattle breeding, Paris, vol. 2, pp. 469–490. INRA, Paris.Google Scholar
Bennett, G. L., Meyer, H. H. and Kirton, A. H. 1988. Effects of selection for divergent ultrasonic fat depth in rams on progeny fatness. Animal Production 47: 379–386.Google Scholar
Bishop, S. C. 1993. Selection for predicted carcass lean content in Scottish Blackface sheep. Animal Production 56: 379–386.Google Scholar
Cameron, N. D. and Bracken, J. 1992. Selection for carcass lean content in a terminal sire breed of sheep. Animal Production 54: 367–377.Google Scholar
Cameron, N. D. and Smith, C. 1985. Estimation of carcass leanness in young rams. Animal Production 40: 303–308.Google Scholar
Casu, S., Carta, R. and Flamant, J. C. 1975. Amelioration genetique de la production laitiere des brebis Sardes. I. Heritabilites et correlations entre caracteres. Genetics, Selection, Evolution 7: 73–90.CrossRefGoogle Scholar
Ch'ang, T. S. and Rae, L. A. 1972. The genetic basis of growth, reproduction and maternal environment of the ewe. Australian Journal of Agriculture Research 23: 149–165.Google Scholar
Collas, G. 1979. Fertility in the ewe after artificial insemination with fresh and frozen semen at the induced oestrus, and influence of the photoperiod on the semen quality of the ram. Livestock Production Science 6: 153–166.CrossRefGoogle Scholar
Flamant, J. C. and Barillet, F. 1982. Adaptation of the principles of selection for milk production to milking ewes: a review. Livestock Production Science 9: 549–559.Google Scholar
Forrest, P. A. and Bichard, M. 1974. Analysis of production records from a lowland sheep flock. 3. Phenotypic and genetic parameters for reproductive performance. Animal Production 19: 33–45.Google Scholar
Hinks, C. J. M. 1978. The use of centralised breeding schemes in dairy cattle improvement. Animal Breeding Abstracts 46: 291–297.Google Scholar
Hopkins, I. R. 1978. Some optimum age structures and selection methods in open nucleus breeding schemes with overlapping generations. Animal Production 26: 267–276.Google Scholar
Jackson, N. and Turner, H. N. 1972. Optimal structure for a co-operative nucleus breeding system. Proceedings of the Australian Society of Animal Production 9: 55–64.Google Scholar
Kalaisakis, P., Papadimitriou, T., Zervas, N., Boyazoglou, J. G. T. and Flamant, J. C. 1977. Comparaison des races ovines et Frisonne avec leurs production laitiere croisements en Grece continentale. II. Production laitiere. Genetics, Selection, Evolution 9: 181–203.Google Scholar
Karras, K. 1984. [ZPLAN — a computer program for optimising breeding schemes.] Polykopie Universitaet Hohenheim.Google Scholar
Kominakis, A. 1991. Model calculations for optimising breeding schemes in the Karagouniko dairy sheep of Greece. Ph.D. thesis, University of Hohenheim, Stuttgart, Germany.Google Scholar
Makarechian, M., Farid, A. and Sefidbakht, N. 1977. Lamb growth performance of Iranian fat-tailed Karakul, Mehraban and Naeini breeds of sheep and their crosses with Corriedale and Targhee rams. Animal Production 25: 331–341.Google Scholar
Mavrogenis, A. P., Louka, A. and Robinson, O. W. 1980. Estimates of genetic parameters for pre-weaning and post-weaning growth traits of Chios lambs. Animal Production 30: 271–276.Google Scholar
Niebel, E., Karras, K. and Fewson, D. 1989. A, ZUPLAN. computer program for optimisation of breeding plans. Institut fuer Tierhaltung und Tierzuechtung der Universitaet Hohenheim. Polykopie Universitaet Hohenheim.Google Scholar
Parratt, A. C., Burt, C. M., Bennett, G. L., Clarke, J. N., Kirton, A. H. and Rae, A. L. 1987. Heritabilities, genetic and phenotypic correlations for carcass traits and ultrasonic fat depth of sheep. Proceedings of the sixth conference, Australian Association of Animal Breeding and Genetics, University Western Australia, Perth, pp. 76–78.Google Scholar
Purser, A. F. 1965. Repeatability and heritability in hill sheep. Animal Production 7: 75–82.Google Scholar
Rogdakis, E., Pappas, V. and Papadimitriou, T. 1988. Data analysis from the National Milk Recording Scheme in the Greek Karagouniki sheep breed. Animal Science Reviezv 8: 17–34.Google Scholar
Simm, G. and Dingwall, W. S. 1989. Selection indices for lean meat production in sheep. Livestock Production Science 21: 223–233.Google Scholar
Simm, G. and Murphy, S. V. 1996. The effects of selection for lean growth in Suffolk sires on the saleable meat yield of their crossbred progeny. Animal Production 62: 255–263.Google Scholar
Simm, G., Young, M. J. and Beatson, P. R. 1987. An economic selection index for lean production in New Zealand sheep. Animal Production 45: 465–475.Google Scholar
Taleghani, H., Bennett, J. A. and Riggs, B. L. 1975. Growth rate of fat tail and exotic cross lambs. Journal of Animal Science 41: 283 (abstr.).Google Scholar
Tomov, I. 1969. A note on commercial crossing of Bulgarian fine-wool ewes with rams of English short-wool breeds. Animal Production 11: 107–109.Google Scholar
Wolf, B. T., Smith, C., King, J. W. B. and Nicholson, D. 1981. Genetic parameters of growth and carcass composition in crossbred lambs. Animal Production 32: 1–7.Google Scholar
Zervas, N. P., Boyazoglou, J. G., Kalaisakis, P., Papadimitriou, T. and Flamant, J. C. 1975. Comparaison des races ovines Chios et Frisonne avec leurs croisements en Grece continentale. I. Viabilite et reproduction. Genetics, Selection, Evolution 7: 277–291.Google Scholar