Cytogenetic studies in Atlantic salmon and rainbow trout embryos

Abstract

Bolla. S. 1987. Cytogenetic studies in Atlantic salmon and rainbow trout embryos. - Hereditas 106: 11–17. Lund, Sweden. ISSN 0018–0661. Received February 21, 1986 Haploid and diploid embryos of Atlantic salmon and rainbow trout in the process of development from the gastrula stage to 2/3 of the yolk sack resorption were incubated in colchicin to accumulate cells in the metaphase stage. Haploid karyograms were useful to describe the chromosome distribution. A stable chromosome number was found in salmon, whereas rainbow trout presented more variation. A large part of the inter- and intraindividual variation in chromosome number is associated with a variation of NF. Associations between acrocentrics were frequently noted in metaphases and could partially explain the extended Robertsonian polymorphism described in salmonids. No evidence of sex chromosomes was detected in the two species.