Freshwater growth, smolting, and marine survival and growth of diploid and triploid coho salmon ( Oncorhynchus kisutch)

• Published in: Aquaculture 1995-11, Vol.136 (1), p.91-107
• Main Authors: Withler, R.E., Beacham, T.D., Solar, I.I., Donaldson, E.M.
• Format: Article
• Language: English
• Subjects: ANIMAL DEVELOPMENTAL STAGES; Aquaculture; CRECIMIENTO; CROISSANCE; ETAPAS DEL DESARROLLO ANIMAL; Fish; Genetics; GROWTH; ONCORHYNCHUS KISUTCH; Physical growth; Smoltification; STADE DE DEVELOPPEMENT ANIMAL; SUPERVIVENCIA; SURVIE; SURVIVAL; TRIPLOIDIA; TRIPLOIDIE; TRIPLOIDY
• ISSN: 0044-8486; 1873-5622
• DOI: 10.1016/0044-8486(95)01036-X

Variation in weight, growth, survival, and smolting was examined for nine fullsib families of diploid and triploid coho salmon ( Oncorhynchus kisutch) from the Quinsam River B.C. Diploids survived substantially better than triploids from fertilization to hatching (94% vs. 43%), from hatching to ponding (96% vs. 76%), during freshwater rearing (92% vs. 75%), and during marine rearing (81% vs. 60%). About 77% of the diploids marked with coded wire (CW) tags smelted, whereas only 63% of the corresponding triploids smoked. About 71% of the diploids marked with passive integrated transponder (PIT) as well as CW tags smolted, whereas only 39% of the triploids carrying both types of tags smolted. Diploids were 65% heavier than the triploids at smolting, and 70% heavier after two summers of marine rearing. Marine growth of diploids was significantly faster than that of the triploids during the spring and summer of the year of maturity. The biomass of the diploid cohort was over three times greater than that of the triploid cohort at the termination of the experiment. Ploidy by family interactions for the characters examined were greatest during freshwater and early marine rearing. Although poor triploid performance was observed in this experiment, relative productivity may be enhanced by rearing triploids in isolation from diploids, or by a judicious choice of the triploid strain.