Showing papers on "Molecular breeding published in 1981"

Quantitative genetics in fish breeding

Abstract: Part I. The fish farming industry in Europe. A brief description of the industry in Europe is given with emphasis on present and future levels of production, major areas of research and patterns of development within the industry. Part II. A review of cruantitative genetics in fish breeding. In recent years there has been increasing research activity in quantitative genetics of farmed fish, especially relating to the salmonid species. This review covers all major aspects of quantitative genetics which are of direct or potential relevance to improving the efficiency of production of farmed fish. Part III. Genetic variation in food conversion efficiency and growth in Rainbow trout. This type of work has not previously been undertaken because of difficulty in measuring food consumption of fish on a sufficiently large scale. This problem was overcome by the development of a system to estimate food consumption through consideration of metabolic rate (via oxygen consumption) and the energy component of growth. 231 full sib families of young Rainbow trout were tested in this system over a two year period. The family mean heritabilities of food conversion efficiency, growth and food consumption were estimated at 3 ± 10%, 26 ± 12% and 41 ± 13% respectively. Phenotypic and genetic correlations of family means for these traits were all close to unity. It is concluded that selection for improved food conversion is of little value.