Research: Fermented yeast in rainbow trout

Effects of Hilyses, fermented Saccharomyces cerevisiae (S. cerevisiae), on growth, body composition and skin mucus immune components in rainbow trout (Oncorhynchus mykiss) were quantified.

 

Ninety rainbow trout (105 ± 5g) were randomly assigned to 2 groups in triplicates and fed dietary Hilyses (5 g/kg) or control diet without Hilyses for 50 days.

 

Results of this study demonstrated that growth performance increased significantly by the dietary yeast supplement; however body composition was not affected in treatment group.

At the 45^th and 50^th day of feeding trial, results of mucus samples demonstrated that yeast supplementation in treatment group significantly promoted enzyme activities, namely lysozyme, protease, alkaline phosphatase and esterase compared to control group.

Significant increases were also observed in haemagglutination and antibacterial activity against Yersinia ruckeri in fish fed treatment diet.

Conclusion
The present study suggests that fermented S. cerevisiae may effectively promote the growth performance and skin non-specific immune parameters in rainbow trout.