Numerical and structural chromosome polimorphism in fish species: Carassius auratus gibelio b. and alburnus alburnus L.

Abstract

The paper presents the results of cytogenetic investigations of the fish species Carassius auratus gibelio, B. and Alburnus alburnus, L. Karyotype definitions are given for fish caught at different localities in Serbia. Within the bisexual population of the silver carp Carassius auratus gibelio B., we observed variability in the number of the last, smallest akrocentrics (2n=100_ 22-4). These variating accessory chromosomes were called Banalogues. We established the number of chromosomes (3n=150+8 and 3n=150+10) and gave the karyotype characteristics for gynogenetic lines of triploid females. We pointed out that the existing clones differ in the number of chromosomes, i.e. in the number of Banalogues, which are also probably the cause of the occurence of - gynogenetic karyoclones. In the species Alburnus alburnus, L., we established the existence of modified karyotipes with a large metacentric - Robertson's fusion, translocation probably formed by the two biggest akrocentrics. We examined the possibility of maintaining variability in populations of this specie. The results are discussed in comparison to disorders which result from these changes in reproduction, and the possible consequences that can be expected in the offispring.

Keywords

• karyotipe
• fish
• chromosomes
• numerical karyotipe aberrations
• poliploidia
• gyonogenesis
• structural chromosomal aberrations
• Robertson's translocation
• Carassius auratusgibelio
• B.
• Alburnus alburnus L.