Chromosomal and electrophoretic analyses of hybrids between grass carp and bighead carp (Pisces: Cyprinidae).
155 hybrids produced by crossing Hypophthalmichthys nobilis ♂♂ with Ctenopharyngodon idella ♀♀ included 101 diploid and 54 triploid individuals with 48 and 72 chromosomes resp. Compared with triploids, diploid hybrids showed a higher frequency of morphological abnormalities, and were generally smaller. Lactate dehydrogenase and esterase isozymes of the parent species were expressed in the hybrids. The data obtained were consistent with control of lactate dehydrogenase by the 3 known loci, A, B and C. The C locus was active only in the liver. Liver esterases were inherited codominantly.