Effect of ploidy on scale-cover pattern in linear ornamental (koi) common carp Cyprinus carpio

• Published in: Journal of fish biology 2012-09, Vol.81 (4), p.1201-1209
• Main Authors: Gomelsky, B., Schneider, K. J., Glennon, R. P., Plouffe, D. A.
• Format: Article
• Language: English
• Subjects: Animals; Breeding; Carps - anatomy & histology; Carps - genetics; Cyprinus carpio; Diploidy; Female; flow cytometry; Freshwater; gene expression; genetics; inheritance; Male; meiosis; Phenotype; phenotypic segregation; Triploidy
• ISSN: 0022-1112; 1095-8649
• DOI: 10.1111/j.1095-8649.2012.03398.x

The effect of ploidy on scale‐cover pattern in linear ornamental (koi) common carp Cyprinus carpio was investigated. To obtain diploid and triploid linear fish, eggs taken from a leather C. carpio female (genotype ssNn) and sperm taken from a scaled C. carpio male (genotype SSnn) were used for the production of control (no shock) and heat‐shocked progeny. In heat‐shocked progeny, the 2 min heat shock (40° C) was applied 6 min after insemination. Diploid linear fish (genotype SsNn) demonstrated a scale‐cover pattern typical for this category with one even row of scales along lateral line and few scales located near operculum and at bases of fins. The majority (97%) of triploid linear fish (genotype SssNnn) exhibited non‐typical scale patterns which were characterized by the appearance of additional scales on the body. The extent of additional scales in triploid linear fish was variable; some fish had large scales, which covered almost the entire body. Apparently, the observed difference in scale‐cover pattern between triploid and diploid linear fish was caused by different phenotypic expression of gene N/n. Due to incomplete dominance of allele N, triploids Nnn demonstrate less profound reduction of scale cover compared with diploids Nn.