ISOZYME ANALYSIS DEMONSTRATES A HIGH PROPORTION OF HYBRIDS IN A HATCHERY STOCK OF PELED (COREGONUS PELED) FROM CZECH REPUBLIC

摘要

Whitefish (Coregonus lavaretus) and peled (C. peled) reared in a hatchery (Jindrichuv Hradec, Czech Republic) were sampled and examined for genetic purity of their breeding stocks. Pyloric caeca number ranged from 131 to 256 in whitefish and from 88 to 149 in peled, so that this character alone did not permit identification of whitefish. and peled specimens. Number of gill rakers ranged from 24 to 34 in whitefish and from 48 to 67 in peled. As the gill raker numbers did not overlap, this character could he considered as a species-specific identification marker. However, electrophoretic examination of enzyme products of the diagnostic loci: GPI-A1*, G3PDH-3 *, sSOD*, and sMEP-3,4* showed that over 30% of fish morphologically classified as peleds werebiochemically identified as whitefish/peled hybrids. Management of hatchery breeding stocks of whitefish and peled should include electrophoretic examination of spawners and culling of specimens identified as hybrids.