A rapid, non-sacrificial chromosome preparation technique for freshwater teleosts

Abstract

The use of fin epithelium from the tilapia, Oreochromis mossambicus, and the grass carp, Ctenopharyngodon idella, was investigated to provide a rapid, non-sacrificial procedure for determining ploidy. A combination of colchicine, prolonged hypotonic treatment, dissociation of cells followed by Giemsa staining makes it possible to achieve good quality metaphase chromosome spreads using small fish without the use of sterile conditions, centrifuges or sacrificing the specimen. In situations such as the induction of triploidy or tetraploidy, it is necessary to have a quick, reliable method of assessing the results of experimental design. The technique presented in this report provides numerous, well-spread metaphase chromosomes with a tissue handling time of less than 2 h.