[Otolith carbon and oxygen stable isotopes in laboratory-reared Schizothorax kozlovi].

In order to investigate the role of otolith carbon (δC) and oxygen (δO) stable isotopes in identification of freshwater fish stocks, otolith δC and δO of cultured Schizothorax kozlovi at different ages were measured by stable isotope mass spectrometer. The relationships between otolith δC / δO and environment were discussed. The results showed that δC and δO values of S. kozlovi at age 1 were not significantly correlated with otolith mass, but both were significantly different between lapillus and asteriscus. The average lapillus δC and δO values of S. kozlovi at different ages were (-9.58±0.06)‰ and (-8.33±0.17)‰, respectively. There was no significant difference of lapillus δC and δO between the sexes, but with significant difference among diffe-rent ages. The correlation of δC with δO was an effective method in identification of different culture stocks of S. kozlovi, which indicated the isotopic signatures of otolith could be used as a method to identify freshwater fish stocks.