Evaluation of Toxicity of Dietary Chelated Copper in Juvenile Olive Flounder, Paralichthys olivaceus, Based on Growth and Tissue Copper Concentration

Abstract

The present study was conducted to determine the safe and toxic levels of dietary copper in juvenile olive flounder, Paralichthys olivaceus, fed Mintrex® copper, a chelated dietary copper source. Fish averaging 3.8 ± 0.13 g (mean ± SD) were fed 1 of 10 diets (n = 3) containing 7 (Cu0), 10.4 (CuM5), 15.8 (CuM10), 24.9 (CuM20), 43.4 (CuM40), 82.1 (CuM80), 158 (CuM160), 308 (CuM320), 658 (CuM640), and 1267 (CuM1280) mg Cu/kg diet. At the end of 12 wk of feeding trial, weight gain (WG), specific growth rate, and protein efficiency ratio of fish fed CuM5 and CuM10 diets were significantly higher than those fed CuM80, CuM160, CuM320, CuM640, and CuM1280 diets (P < 0.05). Survival of fish fed Cu0, CuM5, CuM10, CuM20, and CuM40 diets was significantly higher than those of fish fed CuM320, CuM640, and CuM1280 diets. Whole‐body lipid content of fish decreased while whole‐body ash increased with dietary copper levels. Whole‐body and tissue copper concentrations increased with dietary copper levels. Although ANOVA test suggested that the toxic level of dietary Cu in juvenile olive flounder, P. olivaceus, could be 320 mg/kg diet, broken‐line analysis of WG indicated a level of 286 mg/kg diet when Mintrex®Cu is used as the dietary copper source.

Dietary copper requirement of fingerlingHeteropneustes fossilisfor formulating copper‐balanced commercial feeds

“…However, significantly lower values were recorded in fish that were fed diet Cu1 and higher values in fish that were fed diets Cu6 and Cu7. This pattern of high copper accumulation in muscle of H. fossilis fed diets containing higher levels than required is similar to previous reports for other species such as S. Salar (Lorentzen et al, ); Paralichthys olivaceus (Mohseni, ); and O. niloticus × O. aureus (Tang et al, ). Muscle is the edible part of fish, and hence, it is imperative to maintain the residual content of toxic minerals in the range of safe levels for human consumption as per the guidelines for food (MAFF, ).…”

“…Paralichthys olivaceus (Mohseni, 2012); and O. niloticus × O. aureus (Tang et al, 2017). Muscle is the edible part of fish, and hence, it is imperative to maintain the residual content of toxic minerals in the range of safe levels for human consumption as per the guidelines for food (MAFF, 2000).…”

Tissue concentrations as the dose metric to assess potential toxic effects of metals in field‐collected fish: Copper and cadmium

“…Fish from the Warm Springs area of the Clark Fork River exhibited significant increased lipid peroxidation products and lower concentrations of Ca þ2 in blood at a whole-body Cu concentration of approximately 1.6 mg/g wet weight, an increase of 2Â over control fish [36]. Mohseni et al [37] observed reduced lipid content, reduced feed conversion efficiency, protein efficiency ratio, and whole-body protein content at concentrations between 1.5 mg/g and their growth impairment concentration (3.5 mg/g) after 84 d of dietary exposure, which were all above background concentrations.…”

Dietary copper requirement of fingerlingChanna punctatus(Bloch) based on growth, feed conversion, blood parameters and whole body copper concentration

“…The copper status of the experimental fish was assessed by measuring whole body, liver and serum copper concentrations (Lorentzen, Maage & Julshamn ; Mohseni et al . , ). In this study, the whole body copper concentrations responded to dietary copper and reflected significant increment with the increasing levels of dietary copper indicating that higher levels of dietary copper could not be eliminated and accumulated in tissues.…”

“…Dietary requirements for copper have been quantified for several fish species such as common carp Cyprinus carpio , rainbow trout Salmo gairdneri , Atlantic salmon S. salar , channel catfish Ictalurus punctatus , hybrid tilapia Oncorhynchus niloticus × Oncorhynchus aureas , Malabar grouper Epinephelus malabaricus (NRC ); yellow catfish Pelteobagrus fulvidraco (Tan et al . ); olive Flounder Paralichthys olivaceus (Mohseni, Park, Lee, Okorie, Browdy, Bharadwaj & Bai ), beluga Huso huso (Mohseni, Pourkazemi & Bai ), Nile tilapia Oreochromis niloticus (Damasceno, Fleuri, Sartori, Amorim, Pezzato, Silva, Carvalho & Barros ), Russian sturgeon Acipenser gueldenstaedtii (Wang, Li, Zhu, Du, Qin & Chen ).…”