Fish Feeds in Aquaponics and Beyond: A Novel Concept to Evaluate Protein Sources in Diets for Circular Multitrophic Food Production Systems

Abstract

With the general objective of optimizing internal nutrient recycling, circular multitrophic food production systems, e.g., combining fish, plant, and insect larvae production, rely on the quality and composition of sustainable nutritional inputs. Therefore, differences in dissolved and solid nutrient excretion patterns produced by Nile tilapia (Oreochromis niloticus) reared in recirculating aquaculture systems (RAS) with 5% daily water exchange and fed black soldier fly meal (BSFM), poultry by-product meal (PM), poultry blood meal (PBM) and fish meal (FM) as single protein sources were investigated to evaluate the potential for creating specific fish meal-free diets. Fish fed the FM and PM diet showed the significantly best (p < 0.05) and among each other similar (p > 0.05) growth performance (specific growth rate (SGR): 2.12 ± 0.04/2.05 ± 0.11; feed conversion ratio (FCR): 0.86 ± 0.03/0.92 ± 0.01), whereas the PBM diet caused significantly reduced performance (SGR: 1.30 ± 0.02; FCR: 1.79 ± 0.05) in comparison to the FM/PM diet as well as the BSF diet (SGR: 1.76 ± 0.07; FCR: 1.11 ± 0.05). The FM and PM diet resulted in a faster increase and significantly higher dissolved nitrogen and phosphorus levels, while the BSF diet caused faster accumulation and significantly elevated levels of dissolved potassium, magnesium, and copper. The PBM diet resulted in the feces with the significantly highest nutrient density (gross energy, crude protein, and amino acids) but overall much lower dissolved nutrient levels in the water. Results are discussed with regard to implications for developing circular multitrophic food production systems.

Valuation of Nutrient Utilization, Protein Requirement and Proximate Assessment of an Ecotype Tilapine ‘Wesafu’ Fingerlings Reared in Earthen Pond

“…The highest food conversion ratio was observed in the fry feeds with Diet 2 crude protein with the value of 0.32 ± 0.57 cumulative. The other feeds 30%, 35% and 45% crude protein recorded 0.25 ± 0.04, 0.32 ± 0.57 and 0.25 ± 0.04 respectively which were similar to [43]. The highest cumulative gross food conversion efficiency was recorded in the fry fed with 532.14 ± 131.12 and the lowest gross food conversion efficiency was recorded in fry fed with 35% crude protein with the value of 412.48 ±105.57 corresponding to the observations of [41,42].…”

Collagen Derived from Fish Industry Waste: Progresses and Challenges

“…The enormous amount of valuable protein that could be extracted [ 1 , 2 , 3 , 4 , 5 ] (about 30–40% of the total weight), is one of the most appealing aspects of seafood by-products. More than 20 million tons of them are produced annually from the fish tissues that are discarded as waste, including fins, heads, skin, and viscera [ 6 , 7 , 8 ]. Because of their elevated protein content, absence of disease transmission risks, high bioactivity, and less considerable religious and ethical restrictions, the use of fish by-products as a new source of collagen has drawn increasing attention [ 9 , 10 , 11 ].…”

Growth performance and nutritional composition of Clarias gariepinus in flood-and-drain aquaponics coupled with three species of leafy vegetable

“…This study cannot convincingly ascertain whether feed uptake was higher in aquaponics, but this is likely to be the case. Studies have reported better feed conversion efficiency in Nile tilapia raised in aquaponics than in those raised in conventional fishponds (Amin et al, 2021; Shaw et al, 2022; Strand et al, 2007). An important observation in the aquaponic fish tank was the presence of slimy cyanobacteria (Figure 5), which increased with time and has been reported to significantly contribute to more than 10% of fish protein intake and affect their gut microbiome(Rosenau et al, 2021).…”