Impact of black soldier fly (Hermetia illucens) fresh meal on the growth performance, digestive enzymes, hematology, and intestinal histology of cork fish (Channa striata)

Black Soldier Fly (BSF) is an alternative ingredient for Fish Meal (FM) which is expected to reduce aquaculture operational costs and positively impact fish growth and health. The effect of BSF fresh meal on growth response, digestibility, intestinal hematology, and intestinal histology of cork fish was investigated. The BSF experiment with mixed percentages as treatments, by 20%, 50%, 80%, and 100%, was repeated four times. Furthermore, there were 50 individuals/m3 cork fish with an average weight of 1.6 ± 0.05 g distributed in each treatment. An increase in BSF influences a significant decrease in the Relative Growth Weight (RGW) and Specific Growth Rate (SGR) while the Feed Conversion Ratio (FCR) value has improved. The enzymes were significantly increased, and the histological morphology of the intestine was normal. The highest leukocytes and erythrocytes reached 5.29 ± 1.08 × 10$^{4}$/mm$^{3}$ and 3.22 ± 1.37 × 10$^{6}$/mm$^{3}$, within the normal range and slightly above the threshold of 3.00 × 10$^{6}$/mm$^{3}$. Meanwhile, BSF fresh meal as a substitute feed recommended for cork fish is not more than 20%, which can impact better growth and digestibility.