Biochar From Pulp and Paper Mill Sludge: Co-Pyrolysis With Bentonite, Nutrient Retention and Leachability

Considering the growing demand for food to support the human population, along with the depletion of natural resources and global climate change, this case study presents a potential solution for fish meat production by utilizing a system that mimics the natural growing conditions of rainbow trout - Oncorhynchus mykiss (Walbaum, 1792), and also the associated problems related to microbial infections. Therefore, trout fry was used to populate circular tanks (T1-T4), where they were fed four types of commercial feed, one of the feeds being supplemented with 10% Nannochloropsis sp. flakes. After eight weeks, the impact of the feed on the length weight relationship, growth type, morphology, and body indices of the rainbow trout was assessed. The results showed that the feed formulas do not significantly influence growth parameters. In tandem, due to massive infections, a histological characterization was performed to evaluate the fish's adaptability to feeding and the impact of environmental conditions on the gastrointestinal tract. Our study confirmed that Aeromonas veronii species was connected to septicemia and skin lesions in rainbow trout.