Enrichment of Artemia nauplii with squid and catfish oil by-products enhances survival, growth, and stress resistance in Thai mahseer (Tor tambroides) larvae

The potential of enriched live feeds, such as Artemia nauplii, to enhance the growth performance of Thai mahseer (Tor tambroides) larvae during the larviculture phase is not yet fully understood. This study evaluated the effects of Artemia enriched with squid oil (FSO) and Pangasius catfish oil (FCO) emulsions- on proximate and fatty acid composition of Artemia salina nauplii and larval, larval survival, growth, and tolerance to air exposure stress. Six enrichment treatments with varying FSO and FCO proportions were prepared: P0 (control), P1, P2, P3, P4, and P5. Feeding trials were conducted for 21 days using standardized larval densities, and fatty acid profiles were analyzed via gas chromatography. Results showed that Artemia salina nauplii enriched with P2 had the highest eicosapentaenoic acid (EPA, C20:5n-3), P1 had the highest docosahexaenoic acid (DHA, C22:6n-3), and P5 contained the highest oleic acid (C18:1n-9) and linoleic acid (C18:2n-6). Among all treatments, P1 enrichment most effectively improved larval survival, growth, and stress tolerance. Larvae fed P1 Artemia salina nauplii also exhibited higher DHA and highly unsaturated fatty acids (HUFA) levels compared to other treatments. Under these experimental conditions, P1 produced a DHA to EPA ratio of 2.89 in Artemia salina nauplii, making it the most suitable option for early feeding of Thai mahseer larvae.