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

Abstract

Dietary copper requirement of Heteropneustes fossilis (6.74 ± 0.03 g) was determined by feeding purified diets containing same protein (400 g/kg) and gross energy (17.89 kJ/g) but different levels of copper for 12 weeks. Graded amount of CuSO4.5H2O (0, 1.96, 3.93, 5.89, 7.86, 9.82, 11.79 mg/kg) was supplemented to basal diet to attain desired dietary copper levels (0, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 mg/kg). Analysed dietary copper concentrations were 4.28, 4.63, 5.28, 5.70, 6.19 and 6.69 mg/kg. Absolute weight gain, feed conversion ratio and protein gain improved with the increasing levels of dietary copper up to 5.28 mg/kg. Further inclusion of copper at a level of 5.70 mg/kg did not improve the above parameters. Significantly higher (p < .05) plasma ceruloplasmin, liver copper‐zinc superoxide dismutase, catalase activities and lower thiobarbituric acid reactive substances were evident in fish receiving diets with 5.28 and 5.70 mg/kg copper compared to other groups. Whole body and liver copper concentrations increased significantly (p < .05) with increasing dietary copper levels. Quadratic regression analysis of absolute weight gain, feed conversion ratio, protein gain and broken‐line regression analysis of plasma ceruloplasmin activity and liver TBARS value against the variable dietary copper levels depicted the dietary copper requirements for fingerling H. fossilis in the range of 5.24–5.68 mg/kg.

Effects of dietary Cu nanoparticles on growth performance, physiology and bioaccumulation in Asian walking catfish (Clarias batrachus)

“…High bioavailability of Cu in fish diet can decrease the need for Cu supplements and the excreted Cu in wastes, which accumulate, pollute the rearing water, and harm the fish's health. Many studies have investigated the effective role of dietary Cu concentrations and types on various fish species including Sparus aurata (Tseng et al, 2023), Heteropneustes fossilis (Zafar and Khan, 2019), Channa punctatus (Abdel-Hameid et al, 2016), Larimichthys croceus (Li et al, 2016) and Ctenopharyngodon idella (Tang et al, 2013). Bioavailability of Cu is depending on its available forms, concentration, water quality interactions with other elements, age, size and fish species (Eisler, 2000).…”