Variability of blood proteins in sturgeon ontogenesis and possible aspects of evolution in the family Acipenseridae

The developmental changes in blood proteins of three sturgeons genera Acipenser, Huso, and Pseudoscaphirhynchus (fam. Acipenseridae), have been studied using immunological methods. Heterochronicity and staging of protein development are revealed. Initially, proteins defining the specificity of immunoelectrophoregrams and subject to inconsiderable changes with fish growth are formed. The formation of transferrins is completed in the latest turn. Patterns of development do not depend on the ecology of anadromous and potamodromous forms of sturgeons. This results in the monotypic immunoelectrophoregrams of blood proteins in adult individuals of ten fish species. It is suggested that the variability of blood proteins in the ontogenesis of sturgeons reflects the evolution of this fish through consecutive adaptation to sea waters of different salinities and transition of ancient ancestors to the anadromous mode of life under conditions of oceanic salinity. The modern potamodromous sturgeons may have originated as a result of the return of anadromous forms to life in fresh waters.