Black Soldier Fly Larvae's Optimal Feed Intake and Rearing Density: A Welfare Perspective (Part II)

Area of Science:

• Insect farming
• Animal welfare
• Sustainable agriculture

Background:

• The black soldier fly (Hermetia illucens L.) is crucial for the growing insect rearing sector.
• Ensuring insect welfare is essential for sustainable large-scale operations, adapting frameworks like the Five Freedoms.
• Optimizing feed and rearing density are critical factors for larval nutrition and well-being.

Purpose of the Study:

• To determine optimal feeding rates and rearing densities for black soldier fly larvae.
• To evaluate the impact of different dietary regimes (Control vs. Omnivorous) on larval performance.
• To provide insights for enhancing welfare and efficiency in insect farming.

Main Methods:

• Two trials were conducted: one testing feeding rates (50, 100, 200 mg/larva/day) and another testing rearing densities (5, 10, 15 larvae/cm²).
• Larvae were fed either a Control (commercial laying hen feed) or Omnivorous (vegetable and meat) diet.
• Performance parameters included larval weight, frass biomass, growth rate, substrate reduction, feed conversion ratio, survival, and chemical composition.

Main Results:

• Optimal feeding rates were identified as approximately 90 mg/larva/day for the Omnivorous diet and 175 mg/larva/day for the Control diet.
• Optimal rearing densities were found to be 5 larvae/cm² for the Omnivorous diet and 7.57 larvae/cm² for the Control diet.
• These conditions promoted optimal growth performance and ensured larval well-being.

Conclusions:

• Specific feeding rates and rearing densities are crucial for maximizing black soldier fly growth and welfare.
• Findings support the implementation of improved welfare practices and optimized management in insect farming.
• This research contributes to the efficiency and sustainability of the expanding insect farming industry.