Bactericidal Activity of Serum of All-female Triploid Rainbow Trout

Abstract

The sera of all-female triploid rainbow trout Oncorhynchus mykiss were compared with those of diploids in bactericidal activity against Escherichia coli from April to December. The bactericidal activity of the diploid sera showed a marked decrease during their maturation and spawning period. The sera of triploids, however, kept high bactericidal activity through the experimental period.
These results were supposedly due to the reproductive sterility of female triploids and might explain the fact that triploids showed better survival than diploids during reproductive period.