On-farm validation of black soldier fly larvae meal as a sustainable replacement for shrimp meal in rainbow trout diets in the mid hills of Nepal
Paper Details
On-farm validation of black soldier fly larvae meal as a sustainable replacement for shrimp meal in rainbow trout diets in the mid hills of Nepal
Abstract
Rainbow trout (Oncorhynchus mykiss) aquaculture in Nepal faces constraints regarding high feed costs and the sustainability of marine-derived proteins. This study validated the on-farm partial replacement of shrimp meal with Black Soldier Fly Larvae Meal (BSFLM). Juvenile trout in Rasuwa, Nepal, were fed four isonitrogenous, isolipidic diets for 90 days: Control (100% shrimp meal), BSF25 (25% replacement), BSF50 (50%), and BSF75 (75%). Results indicated that the BSF25 treatment achieved the highest final weight (23.13 ± 0.13 g) and Specific Growth Rate (SGR: 1.34 ± 0.01 %/day), significantly outperforming the control (14.39 g; 0.81 %/day). Feed efficiency was optimal in BSF25, showing the lowest Feed Conversion Ratio (FCR: 1.49 ± 0.02) and the highest Protein Efficiency Ratio (PER: 1.50 ± 0.02). Water quality monitoring showed stable temperature and pH, and significantly higher dissolved oxygen in BSFLM groups, correlating positively with growth. Survival rates remained high in Control and BSF25 (84%) but dropped significantly at BSF75 (48.27%). In conclusion, replacing shrimp meal with 25% BSFLM optimizes growth, feed utilization, water quality conditions, and survival. Higher inclusion levels negatively affected performance. These findings support BSFLM as a sustainable, cost-effective protein alternative for Nepalese trout aquaculture.
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Ishori Singh Mahato, Krishna Paudel*, Sunita Chand, Anshuka Bhattarai, 2025. On-farm validation of black soldier fly larvae meal as a sustainable replacement for shrimp meal in rainbow trout diets in the mid hills of Nepal. Int. J. Biosci., 27(6), 189-200.
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