The Impact of Microalgae-Based Diet Enriched Mesocyclopsaspericornis Copepod on the Growth Performance and Biochemical Assessment of Ornamental Fish (Brachydanio rerio)

Abstract

The cultivation of emerging species in aquaculture and the aquarium industry presents challenges, particularly during the sensitive larval stage, which often has a small mouth. Developing appropriate early feeding protocols is crucial. Copepods have gained recognition as a viable alternative to traditional live fish feeds, as they are natural prey for many fish species and do not necessarily require additional nutritional enrichment. This study aimed to assess the effect of enriching Mesocyclopsaspericornis with different microalgae (Spirulina, Azolla, Chlorella) when fed to Brachydanio rerio, focusing on growth, survival, and biochemical performance of the ornamental fish. Results revealed that Brachydanio rerio exhibited the highest specific growth rate (SGR) when fed with copepods enriched with Spirulina (1.49±0.022), and the highest survival rate was observed when copepods were enriched with Spirulina (93.4±2.549). Further analysis of the biochemical composition of enriched copepods indicated that Chlorella resulted in the highest protein and carbohydrate content, along with lower lipid content compared to other enrichment groups. This suggests that microalgae, particularly Spirulina and Chlorella can serve as a potential feed to enhance the nutritional status of copepods and support the early stages of fish development.