A Circular Bioeconomy Model for Oaxaca: Integrating Entomophagy and Zootechnical Validation in Small-Scale Tilapia Farming

Global population growth necessitates sustainable food systems, positioning Circular Bioeconomy as a key transition framework. In Oaxaca, Mexico, semi-intensive tilapia aquaculture faces economic viability issues due to a critical reliance on expensive external commercial feeds. This study proposes a “Backyard Integrated System” specifically designed for rural contexts with limited capitalization, connecting traditional entomophagy with aquaculture to reduce operational costs and close nutrient cycles. Using a mixed-method approach, we first conducted a sociocultural diagnosis (n = 140), revealing a 97.14% acceptance of insect consumption. Subsequently, to validate technical viability, a long-term (280-day) feeding trial was conducted using standardized insect meals (Tenebrio molitor and Acheta domesticus) as total substitutes (100%) for commercial feed in Nile tilapia (Oreochromis niloticus) diets. Results showed a Feed Conversion Ratio (FCR) of 1.61–1.62, comparable to the commercial control (p > 0.05), while significantly enhancing fillet protein content. Crucially, microbiological analysis confirmed the absence of pathogens in the final product, empirically validating the safety of the waste-to-feed cycle. Consequently, this strategy ensures food sovereignty, decouples producers from volatile external markets, and offers a scalable solution for community resilience without compromising food safety.