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Genetic parameters of weights, ultrasonic muscle and fat depths, maternal effects and reproductive traits in Welsh Mountain sheep

Published online by Cambridge University Press:  18 August 2016

I. Ap Dewi*
Affiliation:
School of Agricultural and Forest Sciences, University of Wales, Bangor, LL57 2UW, UK
M. Saatci
Affiliation:
School of Agricultural and Forest Sciences, University of Wales, Bangor, LL57 2UW, UK
Z. Ulutas
Affiliation:
School of Agricultural and Forest Sciences, University of Wales, Bangor, LL57 2UW, UK
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Abstract

Genetic parameters of weight traits, ultrasonic fat and muscle depths, maternal effects and reproductive traits of Welsh Mountain sheep were estimated based on analyses of data from the nucleus flock of a cooperative breeding scheme. The traits analysed were 12 week weight (TW, no. = 11201), mature weight (MW, no. = 2376), weight at scanning (SW, no. = 1022), muscle depth (SM, no. = 1024), fat depth (SF, no. = 1024), litter weaning weight (LW, no. = 3445) and litter size (LS, no. = 3445). (Co)variance components were estimated in univariate and bivariate animal models. Heritability estimates from univariate analyses were 0.16, 0·49, 0·29, 0·24, 0·22, 0·20 and 0.15 for TW, MW, SW, SF, SM, LW and LS respectively. Genetic correlations among the weight traits were high. There was no detectable correlation between SF and SM. SF and SM were strongly correlated with SW but not with the other weight traits. LW was strongly correlated with MW and SW but not with TW, although the latter analysis was inconclusive. Maternal heritability was similar (0·11) for the univariate analysis of TW and all bivariate analyses involving TW (except for TW v. LW). The permanent environmental effect of dam was generally low (0.02 to 0.04) whilst litter effects were generally high (0·20 to 0·23). The correlation between direct and maternal genetic effects for TW were generally small and non-significant. The maternal genetic effect for TW was moderately correlated with the direct additive effect for MW and SW but was not significantly correlated with the direct additive effect for LS, SM or SF. A very large positive correlation was found between the maternal genetic effect for TW and the direct additive effect for LW. The implications of the results are discussed in the context of selection indices for Welsh Mountain sheep.

Type
Breeding and genetics
Copyright
Copyright © British Society of Animal Science 2002

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References

Al Shorepy, S. A. and Notter, D. R. 1996. Genetic variation and covariation for ewe reproduction, lamb growth and lamb scrotal circumference in a fall-lambing sheep flock. Journal of Animal Science 74: 14901498.Google Scholar
Analla, M., Munoz Serrano, A. and Serradilla, J. M. 1997. Analysis of the genetic relationship between litter size and weight traits in Segurena sheep. Canadian Journal of Animal Science 77: 1721.Google Scholar
Analla, M. and Serradilla, J. M. 1998 Estimation of correlations between ewe litter size and maternal effects on lamb weights in Merino sheep. Genetics, Selection, Evolution 30: 493501.Google Scholar
Bishop, S. C., Conington, J., Waterhouse, A. and Simm, G. 1996. Genotype ✕ environment interactions for early growth and ultrasonic measurements in hill sheep. Animal Science 62: 271277.CrossRefGoogle Scholar
Brash, L. D., Fogarty, N. M., Gilmour, A. R. and Luff, A. F. 1992. Genetic parameters for liveweight and ultrasonic fat depth in Australian meat and dual-purpose sheep breeds. Australian Journal of Agricultural Research 43: 831841.Google Scholar
Bromley, C. M., Snowder, G. D. and Van Vleck, L. D. 2000. Genetic parameters among weight, prolificacy and wool traits of Columbia, Polypay, Ramboulliet and Tarhgee sheep. Journal of Animal Science 78: 846858.Google Scholar
Bromley, C. M., Van Vleck, L. D. and Snowder, G. D. 2001. Genetic correlations for litter weight weaned with growth, prolificacy and wool traits in Columbia, Polypay, Ramboulliet and Tarhgee sheep. Journal of Animal Science 79: 339347.Google Scholar
Burfening, P. J. and Kress, D. D. 1993. Direct and maternal effects on birth and weaning weight in sheep. Small Ruminant Research 10: 153163.Google Scholar
Clarke, J. N., Dobbie, J. L., Jones, K. R., Uljee, A. E. and Wrigglesworth, A. L. 1997. Comparison of weight-selected Romney hoggets for growth and ultrasonic fat and eye muscle dimensions. Proceedings of the New Zealand Society of Animal Production 57: 263.Google Scholar
Clarke, J. N., Nicoll, G. B. and Mowat, C. M. 1998. Genetic parameters for liveweight and live animal ultra-sound fat and eye muscle dimensions in a synthetic terminal sire breed. Proceedings of the New Zealand Society of Animal Production 58: 140142.Google Scholar
Conington, J., Bishop, S. C., Waterhouse, A. and Simm, G. 1995. A genetic analysis of early growth and ultrasonic measurements in hill sheep. Animal Science 61: 8593.Google Scholar
Conington, J., Bishop, S. C., Waterhouse, A. and Simm, G. 1998. A comparison of growth and carcass traits in Scottish Blackface lambs sired by genetically lean or fat rams. Animal Science 67: 299309.Google Scholar
Fogarty, N. M. 1995. Genetic parameters for live weight, fat and muscle measurements, wool production and reproduction in sheep: a review. Animal Breeding Abstracts 63: 101143.Google Scholar
Fogarty, N. M., Brash, L. D. and Gilmour, A. R. 1994. Genetic parameters for reproduction and lamb production and their components and liveweight, fat depth and wool production in Hyfer sheep. Australian Journal of Agricultural Research 45: 443457.Google Scholar
Gilmour, A. R., Cullis, B. R., Welham, S. J. and Thompson, R. 1998. ASREML. NSW Agriculture, Orange, Australia.Google Scholar
Gilmour, A. R., Luff, A. F., Fogarty, N. M. and Banks, R. 1994. Genetic parameters for ultrasound fat depth and eye muscle measurements in live Poll Dorset sheep. Australian Journal of Agricultural Research 45: 12811291.Google Scholar
Hall, S. 1997. Sheepbreeder BLUP development. In Sheep yearbook 1997, pp. 2527. Meat and Livestock Commission, Milton Keynes, UK.Google Scholar
Larsgard, A. G. and Olesen, I. 1998. Genetic parameters for direct and maternal effects on weights and ultrasonic muscle and fat depth of lambs. Livestock Production Science 55: 273278.Google Scholar
Maria, K. G., Boldman, K. G. and Van Vleck, L. D. 1993. Estimates of variances due to direct and maternal effects for growth traits of Romanov Sheep. Journal of Animal Science 71: 845849.Google Scholar
Meat and Livestock Commission. 1988. Sheep in Britain. MLC, Milton Keynes, UK.Google Scholar
Meat and Livestock Commission. 1989. Sheep yearbook 1989. MLC, Milton Keynes, UK.Google Scholar
Meat and Livestock Commission. 2000. Sheep yearbook 2000. MLC. Milton Keynes, UK.Google Scholar
Meyer, K. 1992. Variance components due to direct and maternal effects for growth traits of Australian beef cattle. Livestock Production Science 31: 179204.Google Scholar
Mousa, E., Van Vleck, L. D. and Leymaster, K. A. 1999. Genetic parameters for growth traits for a composite terminal sire breed of sheep. Journal of Animal Science 77: 16591665.CrossRefGoogle ScholarPubMed
Nasholm, A. and Danell, O. 1996. Genetic relationships of lamb weight, maternal ability and mature ewe weight in Swedish finewool sheep. Journal of Animal Science 74: 329339.CrossRefGoogle ScholarPubMed
Notter, D. R. 1998. Genetic parameters for growth traits in Suffolk and Polypay sheep. Livestock Production Science 55: 205213.Google Scholar
Olesen, I. and Husabo, J. O. 1994. Effect of using ultrasonic muscle depth and fat depth on the accuracy of predicted phenotypic and genetic values of carcass traits on live ram lambs. Acta Agriculturæ Scandinavica, Section A, Animal Science 44: 6572.Google Scholar
Pollott, G. 1998. Sheep breeds and breeding in Britain 1996-1997. In Sheep yearbook 1998, pp. 3753. Meat and Livestock Commission, Milton Keynes, UK.Google Scholar
Rao, S. and Notter, D. R. 2000. Genetic analysis of litter size in Targhee, Suffolk and Polypay sheep. Journal of Animal Science 78: 21132120.Google Scholar
Saatci, M., Ap Dewi, I. and Ulutas, Z. 1999. Variance components due to direct and maternal effects and estimation of breeding values for 12-week weight of Welsh Mountain lambs. Animal Science 69: 345352.Google Scholar
Schneeberger, M., Barwick, S. A., Crow, G. H. and Hammond, K. 1992. Economic indices using breeding values predicted by BLUP. Journal of Animal Breeding and Genetics 109: 180187.Google Scholar
Simm, G. 1998. Genetic improvement of cattle and sheep. Farming Press, Ipswich.Google Scholar
Simm, G. and Dingwall, W. S. 1989. Selection indices for lean meat production in sheep. Livestock Production Science 21: 223233.Google Scholar
Snyman, M. A., Erasmus, G. J., Van Wyk, J. B. and Olivier, J. J. 1998. Genetic and phenotypic correlations among production and reproduction traits in Afrino sheep. South African Journal of Animal Science 28: 7481.Google Scholar
Snyman, M. A., Olivier, J. J., Erasmus, G. J. and Van Wyk, J. B. 1997. Genetic parameter estimates for total weight of lamb weaned in Afrino and Merino sheep. Livestock Production Science 48: 111116.Google Scholar
Sousa, W. H. de, Pereira, C. S., Bergmann, J. A. G. and Silva, F. L. R. da. 1999. Estimates of (co) variance components and direct and maternal heritability for growth traits in Santa Ines sheep breed. Revista Brasileira de Zootecnia 28: 12521262.Google Scholar
Thorsteinsson, S. and Eythorsdottir, E. 1998. Genetic parameters of ultrasonic and carcass cross-sectional measurements and muscle and fat weight of Icelandic lambs. In Proceedings of the sixth world congress on genetics applied to livestock production, Armidale, Australia, vol. 24, pp. 149152.Google Scholar
Tosh, J. J. and Kemp, R. A. 1994. Estimation of variance components for lamb weight in three sheep populations. Journal of Animal Science 72: 184190.Google Scholar
Tosh, J. J., Kemp, R. A. and Ward, D. R. 2000. Estimates of direct and maternal genetic paramaters for weight traits and backfat thickness in a multibreed population of beef cattle. Canadian Journal of Animal Science 79: 433439.Google Scholar
Vaez-Torshizi, R., Nicolas, F. W. and Raadsma, H. W. 1996. REML estimates of variance and covariance components for production traits in Australian Merino sheep, using an animal model. 1. Body weight from birth to 22 months. Australian Journal of Agricultural Research 47: 12351249.Google Scholar
Van Wyk, J. B., Erasmus, G. J. and Konstantinov, K. V. 1993. Variance components and heritability estimates of early growth traits in the Elsenburg Dormer stud. South African Journal of Animal Science 23: 7276.Google Scholar
Waldron, D. F., Clarke, J. N., Rae, A. L. and Woods, E.G. 1992. Expected responses in carcass composition to selection for muscularity in sheep. Proceedings of the New Zealand Society of Animal Production 52: 2931.Google Scholar
Waldron, D. F. and Thomas, D. L. 1992. Increased litter size in Rambouillet sheep. I. Estimation of genetic parameters. Journal of Animal Science 70: 33333344.Google Scholar