EFFECTS AND INTERACTIONS OF TAURINE SUPPLEMENTAION IN BROODSTOCK AND LARVAL FEEDS IN CALIFORNIA YELLOWTAIL Seriola lalandi.

Guillaume Salze*, Kevin Stuart, D. Allen Davis, and Mark Drawbridge
School of Fisheries, Aquaculture and Aquatic Sciences
Auburn University, Auburn, AL 36849
gzs0010@auburn.edu

 

Taurine has garnered a lot of attention in recent years, as evidence showed that it was an essential nutrient in a number of teleost species. However, there is a great dearth of information concerning the role of taurine in reproductive output, i.e. egg production and subsequent larval quality. California yellowtail is a solid candidate for aquaculture - yet large fluctuations in survival rates through weaning (20-40%) of larvae are commonly seen. Consequently, a trial was conducted where broodstock of California yellowtail received taurine supplemented or unsupplemented feed (2.67% and 0.28% dietary taurine, respectively), and the resulting eggs and larvae were divided and raised on a taurine-supplemented or unsupplemented protocols. This resulted in 4 treatments at the larval level (combinations of control/taurine-supplemented broodstock - CB or TB - and control/taurine-supplemented larvae - CL or TL).

Discriminant factor analysis of spawn metrics indicate significant differences in the reproductive output from fish fed the taurine-supplemented feed. The difference was primarily driven by significant increases in total eggs per spawn, relative fecundity, percent floating and percent viability. Egg measurements (e.g., egg diameter, oil globule diameter, yolk volume, notochord length) did not significantly contribute to treatment separation. Survival of larvae to 1st feeding was also significantly affected, though only when including hatching success: odds of survival were 36% higher in the larvae from the taurine-supplemented broodstock than those from the control broodstock (logistic regression, p<0.0001).

No larvae of the CB-CL group survived until weaning at 30 days-post-hatch (dph), therefore were excluded from analysis of larval growth. ANCOVA analysis revealed no significant differences between the 3 other treatment groups in terms of live weight or notochord length. However, the larvae in the TB-CL and CB-TL groups were numerically longer and heavier.

Results show that broodstock diets should be supplemented with taurine.