Hmyzí moučka jako zdroj krmiv ve výživě okounovitých ryb, okouna říčního (Perca fluviatilis) a candáta obecného (Sander lucioperca)

The present Ph.D. thesis employed: 1) meta-analysis and systematic approach to investigate the effect of insect meals in diets for aquaculture fish species on production performance and environmental consequences, and 2) in-vivo feeding trials involved frequent-used insect meals, black soldier fly (Hermetia illucens) and yellow mealworm (Tenebrio molitor) in diets for potential aquaculture-oriented percid fishes, Eurasian perch (Perca fluviatilis) and pikeperch (Sander lucioperca), concerning a wide range of parameters. Chapters 2 and 3 provided a comprehensive overview of growth performance indices and environmental impacts of aquaculture species fed dietary insect meals. Accordingly, defatted larval yellow mealworm (T. molitor) and full-fat pupal silkworm (Bombyx mori) are the most promising insects in supporting the specific growth rate of aquatic animals. Chapter 2 also suggested a list of well-known and underexploited insects, which could sustain fish growth at a specific plausible inclusion, including defatted (H. illucens), full-fat fly (Chrysomya megacephala), cricket (Gryllus bimaculatus), grasshoppers (Oxya fuscovittata) and (Zonocerus variegatus) and full-fat moth (Cirina butyrospermi). Chapter 3 revealed that feeding insect meal-containing diets, in comparison to insect-free diets, to aquaculture species reduced the demand for marine-derived forage fish required for farmed fish output, as evidenced by the economic fish-in fish-out ratio and phosphorus waste load but had negative impacts on nitrogen waste and environmental impacts categories, including global warming potential, energy use, land use, water use, acidification, and eutrophication. As demonstrated in Chapter 3, the inclusion of housefly (Musca domestica) at the expense of fishmeal and some plant ingredients in aquatic animal diets considerably decreased land use. These studies suggested the importance of combing feed ingredients to fill the production gap for future aquafeed, meet the nutrient requirement of targeted fish, and sustain environmental benefits. Our works demonstrated that dietary black soldier fly (H. illucens) and yellow mealworm (T. molitor) were well accepted by both percid fishes, Eurasian perch (P. fluviatilis) and pikeperch (S. lucioperca), concerning growth performance. Chapters 4, 6 & 8 revealed that Eurasian perch tolerated dietary H. illucens better than T. molitor, since the former threshold was 40% compared to 6.8% of the latter; nevertheless, the former was accepted by pikeperch at 18%. Chapter 6 evidenced the effects associated with antioxidative enzyme and gut microbiome modulation of highly defatted H. illucens fed to pikeperch. Adding to this, Chapter 7 confirmed that dietary T. molitor did not alter the swimming capacity and metabolism of Eurasian perch, which hinted at fish welfare assurance. The introduction of T. molitor into Eurasian perch diets faces challenges regarding physiological responses and environmental consequences, with substantial levels causing stress to fish and pressuring environmental indices. Our study (Chapter 5) revealed that the stable isotope and mixing model might be used to predict food sources and estimate the proportional contribution of feed components to perch's tissue. Such tools are also helpful to provide insight into complementarity among ingredients in feed formulation