Effect of broodstock holding environment on egg quality in farmed brown trout (Salmo trutta)

Murray, D. SAdams, C. EMcDade, KSolomon, S. EBain, M. M

Brown trout (Salmo trutta) broodstock from a single population were separated prior to spawning andexposed to two different holding environments: a ‘raceway system’ and a ‘tank system’. Eggs were stripped from females and 13 measures of egg qualitywere collected, analysed individually, combined by principle components analysis into an integrated egg quality score which was validated against egg survival.The multivariate egg quality score (PC1) differed for fish held in the tank and raceway systems. Egg survival, chorion breaking strength and chorion Se concentrations were higher in eggs produced by broodstock held in the tank system compared to those in the raceway system. In contrast, chorion concentrations of P and K were higher in eggs from fish held in the raceway system. The results suggest that brown trout broodstock reared in tank systems produced higher quality eggs compared to trout reared in raceways. Finally, this study also indicates that multivariate statistical analysis can be used to determine egg quality from multiple egg parameters.(AU)

1. raceway
2. environment
3. tank
4. multivariate
5. egg
6. chorion