Aquaculture´s sustainability deeply relies on the identification and implementation of alternative raw materials (ARMs) to replace fish meal and oil . One of the main ARMs currently used in fish diets is soybean meal (SBM) that in some regions (e.g. Europe ) has to be imported. Thus, the identification of locally produced crops to substitute SBM is an urgent need to reduce not only the dependency of SBM from third countries,
but also to reduce the carbon footprint. H ere a nutritional dose -response trial was performed to explore the use of red vetchling
(Lathyrus
cicera ) meal (RVM)
in rainbow trout (Oncorhynchus mykiss) diets.
A 90-day feeding trial was conducted to evaluate the effects of different substitution levels (0 %, 8 %, 16 %, 33 %, 66% and 100 %, named as C , T8,
T16 , T33 , T66 and T100 , respectively; isonitrogenous 42% and isolipidic 18%, diets ) of SBM with RVM on growth, and feed utilization of juvenile rainbow trout. A total of 360 juvenile fish of 10 ± 0.5 g maintained under controlled parameters (temperature of 15 ° C, dissolved oxygen > 7 mg/L, etc.) in 500 L tanks connected to a RAS unit (20 fish/tank) were hand-fed at
a daily ration of 3% body weight.
Preliminary results presented here, obtained after 42 days feeding, indicate significant
lower values for wet weight, WG, SGR and FCR only in those fish
fed on the highest substitution (ANOVA,
p> 0.05; Table 1).
Although g rowth performances, as well as other parameters like t he histopathological status of the digestive system
(liver, proximal and distal intestines) , blood biochemistr y (glucose and triglyceride’s plasma content ) and muscle quality
(proximal composition, amino acid and fatty acids
profiles ) will be assessed again at the end of the experimental period.
These results suggest that SBM could be partially replaced up to 66 % by red vetchling meal in rainbow trout feeds.
Acknowledgments: This work was partially funded by “Optimización integral de los sistemas productivos en acuicultura: revalorización de materias primas locales en piensos y en cría de especies en potencial desarrollo (OPTI-ACUA)” project from the European Regional Development Funds (ERDF). F.J. T-S. acknowledges CONACYT for the post-doc fellowship No. 2019–000012-01EXTV-00292. I.F. acknowledges Ramón y Cajal (Ref. RYC2018-025337-I) contract from MICIU and the European Social Fund, “The European Social Fund invests in your future”. Authors also thanks the support from the network LARVAplus (117RT0521) funded by the CYTED.