A bidirectional selection experiment for 8-week body weight in chickens was conducted. In addition to 27 generations of selection, random samples were chosen from each selected line in generations 6, 13, 19 and 26 to initiate lines in which selection was relaxed. Genetic change was evident in the selected high-weight line through the first 75% of the study after which response in the direction opposing selection occurred. Selection for low body weight resulted in considerable reduction in body size, particularly in the last quarter of the study. Correlated responses evaluated were body weight at several ages, conformation, age at onset of lay, various reproductive and egg quality traits and ratio (female: male) of some traits. Data from lines where selection was relaxed indicated that natural selection opposed artificial selection with the effects greater in later generations.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
This is the net price. Taxes to be calculated in checkout.
Barbato GF, Siegel PB, Cherry JA, Nir I (1984) Selection for body weight at eight weeks of age. 17. Overfeeding. Poult Sci 63:11–18
Blohowiak CC, Siegel PB, Van Krey HP (1980) Sexual behavior of dwarf and normal genotypes in divergent growth lines of chickens. Appl Anim Ethol 6:189–201
Burkhart CA, Cherry JA, Van Krey HP, Siegel PB (1983) Genetic selection for growth rate alters hypothalamic satiety mechanisms in chickens. Behav Genet 13:295–300
Clayton GA, Robertson A (1957) An experimental check on quantitative genetical theory. 2. The long-term effects of selection. J Genet 55:152–170
Dunnington EA, Siegel PB, Cherry JA (1984) Delayed sexual maturity as a correlated response to selection for reduced 56-day body weight in White Plymouth Rock pullets. Arch Geflügelkd 48:111–113
Dunnington EA, Siegel PB, Cherry JA, Jones DE, Zelenka DJ (1985) Physiological traits in adult female chickens after selection and relaxation of selection for 8-week body weight. Z Tierz Züchtungsbiol (in press)
Dunnington EA, Siegel PB, Cherry JA, Soller M (1983) Relationship of age and body weight at sexual maturity in selected lines of chickens. Arch Geflügelkd 47:85–89
Eisen EJ (1980) Conclusions from long-term selection experiments with mice. Z Tierz Züchtungsbiol 97:305–319
Falconer DS (1981) Introduction to quantitative genetics, 2nd edn. Longman, London New York
Frankham R (1980) Origin of genetic variation in selection lines. In: Robertson A (ed) Selection experiments in laboratory and domestic animals. Commonwealth Agricultural Bureaux, London, pp 56–68
Hill W (1971) Design and efficiency of selection experiments for estimating genetic parameters. Biometrics 27:293–311
Hill W (1972) Estimation of realised heritabilities from selection experiments. 2. Selection in one direction. Biometrics 28:767–780
Lerner IM (1954) Genetic homeostasis. Wiley and Sons, New York
Marks HL, Siegel PB (1971) Evaluation of the Athens-Canadian randombred population. 1. Time trends at two locations. Poult Sci 50:1405–1411
Middelkoop JH van, Siegel PB (1976) Classification of abnormal chicken eggs. Poult Sci 55:1563–1566
Nordskog AW, Hardiman J (1980) Inbreeding depression and natural selection as factors limiting progress from selection in poultry. In: Robertson A (ed) Selection experiments in laboratory and domestic animals. Commonwealth Agricultural Bureaux, London, pp 91–99
Reddy PRK, Siegel PB (1977) Chromosomal abnormalities in chickens selected for high and low body weight. J Hered 68:253–256
Robertson A (1960) A theory of limits in artificial selection. Proc R Soc London, Ser B 153:234–249
Siegel PB (1962) Selection for breast angle at 8 weeks of age. 1. Short term response and heritabilities. Poult Sci 41: 951–962
Siegel PB (1963) Selection for breast angle at 8 weeks of age. 2. Correlated responses of feathering, body weights and reproductive characteristics. Poult Sci 42:437–449
Siegel PB (1978) Response to twenty generations of selection for body weight in chickens. Proc 16th World's Poult Cong 10:1761–1772
Siegel PB, Dunnington EA (1985) Reproductive complications associated with selection for broiler growth. In: Hill WG, Manson JH, Hewitt D (eds) Poultry genetics and breeding. Longman Group, Harlow, pp 59–72
Skoglund WC, Tomhave AE, Mumford CW (1948) The hatchability of eggs of various sizes. Poult Sci 27:709–712
Verghese MW, Nordskog AW (1968) Correlated responses in reproductive fitness to selection in chickens. Genet Res Camb 11:221–238
Communicated by H. Abplanalp
About this article
Cite this article
Dunnington, E.A., Siegel, P.B. Long-term selection for 8-week body weight in chickens — direct and correlated responses. Theoret. Appl. Genetics 71, 305–313 (1985). https://doi.org/10.1007/BF00252072
- Long-term selection
- Body weight
- Relaxed selection
- Correlated responses