1. Recycling biofloc waste as novel protein source for crayfish with special reference to crayfish nutritional standards and growth trajectory
- Author
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Antonín Kouba, Jan Mráz, Roman Lunda, Petr Dvorak, and Koushik Roy
- Subjects
0301 basic medicine ,Animal feed ,Biomass ,Hepatopancreas ,lcsh:Medicine ,Fresh Water ,Aquaculture ,Astacoidea ,Biochemistry ,Article ,03 medical and health sciences ,Stress, Physiological ,Metals, Heavy ,Animals ,Recycling ,Food science ,lcsh:Science ,Procambarus clarkii ,Waste Products ,Multidisciplinary ,biology ,Chemistry ,Novel protein ,business.industry ,Biological techniques ,lcsh:R ,Proteins ,Heavy metals ,04 agricultural and veterinary sciences ,Cichlids ,biology.organism_classification ,Crayfish ,Animal Feed ,030104 developmental biology ,nervous system ,Bioaccumulation ,040102 fisheries ,0401 agriculture, forestry, and fisheries ,Animal Nutritional Physiological Phenomena ,lcsh:Q ,business ,Zoology - Abstract
Screening of novel feedstuffs, that too for data-deficient (nutritionally) animals, is somewhat ambiguous or problematic. Through systematic meta-analyses, the present study formulated most up-to-date crayfish nutritional standards, against which a recyclable waste (biofloc biomass, BM) from intensive aquaculture systems was assessed as a novel protein source. Growth trajectory dependencies and thermal growth coefficient qualifying for good growth in crayfish (TGC 0.5–0.64 units) were benchmarked. Using these standards and a 7-week growth trial, BM's suitability as a novel protein source for red swamp crayfish Procambarus clarkii was evaluated through its graded inclusions in a commercial feed. Results suggest that BM can elevate growth at 33–66% inclusion in existing feed formulations. Beyond 66% inclusion, BM can deteriorate growth in crayfish due to high ash content (exceeding physiological limit > 14%), arginine deficiency (~ 14–20% lower than an optimum requirement), and insufficient non-protein energy: protein ratio (3.7 cal mg−1). Arginine is perhaps the most critical amino acid in dietary protein for crayfish, and deficient in BM. Although no critical bioaccumulation levels of heavy metals were breached by feeding 100% BM to crayfish, a mineral and heavy metal (Hg) stress seemed plausible. Crayfish raised solely on biofloc may not realize full growth potential.
- Published
- 2020
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