Cytological and biochemical studies in back‐crosses between the hybrid Atlantic salmon × sea trout and its parental species

Abstract

A male hybrid between a female salmon from Lule river in Northern Sweden and a male trout from Ireland has been back‐crossed to a female salmon and a female trout both from Lule river. Eleven months after the crosses had been made no offspring was left in the combination trout × hybrid, while 4 individuals of the combination salmon × hybrid were still alive. The chromosome numbers of the fish studied are: salmon, 2n=58; trout, 2n=80; hybrid, 2n=69; back‐crossed individuals 2n=60, 64 and 66. Various proteins of the different components were analysed. To our knowledge this is the first joint cytological/electrophoretic investigation of hybrids of this salmonid combination. © 1975 Mendelian Society of Lund