Sustainable Poultry Farming in Tanzania through Insect-Based Feeds: A Review of the Potential of Black Soldier Fly Larvae as an Alternative Feed Resource

Poultry farming is one of the fastest-growing livestock subsectors in Tanzania, contributing significantly to food security, nutrition, employment and rural livelihoods. However, its expansion is severely constrained by high feed costs, which account for 60–70% of total production expenses, largely due to reliance on conventional protein sources such as fishmeal and soybean meal. These feed ingredients are expensive, environmentally unsustainable and often limited in supply. This review examines the potential of Black Soldier Fly (Hermetia illucens) larvae (BSFL) as a sustainable, locally producible alternative protein source for poultry feed in Tanzania. The paper synthesizes existing literature on the biology and production of BSF, optimal rearing conditions, substrate utilization, nutritional composition, digestibility, poultry performance outcomes and the environmental and economic sustainability of BSFL production. This review synthesizes existing literature and identifies key research and policy gaps. Evidence indicates that BSFL are rich in protein (35–60%), lipids (15–40%), essential amino acids, minerals and bioactive compounds, with high digestibility comparable to or exceeding that of fishmeal. Feeding trials demonstrate that partial or complete replacement of fishmeal or soybean meal with BSFL meal maintains or improves growth performance, feed conversion efficiency, egg production, gut health and immunity in poultry. Additionally, BSFL production supports circular bioeconomy principles by converting organic waste into valuable feed and frass fertilizer, reducing waste volumes, greenhouse gas emissions and overall feed costs. Despite these advantages, adoption of BSFL farming in Tanzania remains limited due to low farmer awareness, cultural perceptions, regulatory and policy gaps, inadequate technical capacity, limited access to finance, and underdeveloped markets. The review identifies key gaps and proposes integrated strategies for scaling up BSFL-based feed systems, including development of national guidelines and standards, integration into livestock development policies, strengthened research and technology transfer, private sector and development partner engagement, innovative financing mechanisms and consumer sensitization. Coordinated implementation of these measures can enhance feed security, promote sustainable poultry production and position Tanzania as a regional leader in insect-based feed systems aligned with Vision 2050 goals.