Incubation Temperature Effect on Qualitative and Quantitative Composition of Abnormalities and Mortality Rate in Embryogenesis of the Barents Sea Capelin Mallotus villosus (Osmeridae)

Abstract

The development of capelin Mallotus villosus from insemination to total resorption of the yolk is investigated at 5 and 8°C by the assessment of development of each individual (3850 eggs obtained from 77 spawning pairs). In total, ten malformation types are defined in early development. The frequency of their occurrence and embryonic mortality rate during incubation is described. The total malformation number and mortality rate are significantly higher at 8°С than at 5°С. A distinct relationship between early development quality and age or body size of the females is not revealed. In the majority of trials, the progenies of large females are characterized by better quality, but these data are not always significant. The qualitative composition and malformation rate of capelin differ from those observed in Atlantic cod Gadus morhua using the same methods of investigation. In addition, the malformation and mortality rates during early development are substantially lower in capelin than in Atlantic cod.