Rainbow trout broodstock and progenies registration and selection of Yasouj Fishery Research Center in order to breeding

Abstract

Frequently,the development of quantitative traits in livestock based on breeding programs has been more important.In spite of higher selection response in fish than in farm animal, it is no progress in fish breeding programs in some regions such as IRAN, because of little information of genetic variation of stock, disconstructed or undesigned base population, the deterioration of genetic resourse and don’t well informed educated researchers,extension workers and aquaculturists in breeding theory and its practical issues. At first step,in Yasouj Coldwater Fishes Breeding Research Center, in order to conducting combined selection program in rainbow trout broodstock as base population and their offsprings in mixed age parents,150 female and male broods with higher mean weight were selected,striped in 6 stage and eggs were incubated.One-year Fishes(45000 pcs.) of the six groups with higher mean weight in 5 stage were selected(438 pcs.) and remainder was discarded. Before selection, a few fishes of six aged-groups as control group were cultured apart. Difference(p<0.05) induced between mean weight of the selected groups and with control group was because of age difference in them and of no deletion in control group(don’t throw out small individuals) by selection.The whole groups don’t have significant difference (p>0.05) in FCR and FER. Based on results, it isn’t told that difference between experimental and control groups is a result of genetic improvement of growth rate trait induced of selection process in one generation and the continue of this program for several generations in order to reveal the development of a quantitative trait is unevitable and mating of selected broods(438 fish) in a crossbreeding program and the selection of offsprings is essential.