1
|
Abstract
Many traits in farm animals, such as litter size or fleece weight, are the product or ratio of two or more component items. This note seeks to determine the circumstances in which selection directed at the component items is more effective in improvement than selection for the composite trait itself.A change of one per cent in a product trait can be achieved by a change of one per cent in any of its components. The response expected on selection for a product trait or a component is proportional to h2C per cent, where h2 is the heritability and C is the coefficient of variation. Thus selection for a component trait (A) may possibly be more efficient than direct selection for the product trait (X) when is greater than . However, the correlated changes in other component traits would also have to be taken into account.
Collapse
|
2
|
Tallis GM. SAMPLING ERRORS OF GENETIC CORRELATION COEFFICIENTS CALCULATED FROM ANALYSES OF VARIANCE AND COVARIANCE. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1467-842x.1959.tb00271.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
3
|
Sumner R, Bigham M. Biology of fibre growth and possible genetic and non-genetic means of influencing fibre growth in sheep and goats—a review. ACTA ACUST UNITED AC 1993. [DOI: 10.1016/0301-6226(93)90235-a] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
4
|
Bohren BB. Genetic gains in annual egg production from selection on early part-records. WORLD POULTRY SCI J 1970; 26:647-57. [PMID: 5465980 DOI: 10.1079/wps19700021] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
5
|
Evans JV, Turner HN. Haemoglobin type and reproductive performance in Australian Merino sheep. Nature 1965; 207:1396-7. [PMID: 5886046 DOI: 10.1038/2071396a0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
|
6
|
Lipson M, Walls GW. PROCESSING OF WOOL FROM A FLOCK SELECTED FOR HIGH FLEECE-WEIGHT. ACTA ACUST UNITED AC 1962. [DOI: 10.1080/19447016208688761] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|