Effects of the dietary supplementation of copper on growth, oxidative stress, fatty acid profile and skeletal development in gilthead seabream (Sparus aurata) larvae

• Published in: Aquaculture Vol. 568; p. 739319
• Main Authors: Tseng, Yiyen, Eryalçın, Kamil Mert, Sivagurunathan, U., Domínguez, David, Hernández-Cruz, Carmen María, Boglione, Clara, Philip, Antony Jesu Prabhu, Izquierdo, Marisol
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15-04-2023
• Subjects: Bone health; Copper requirement; Gilthead seabream (Sparus aurata) larvae; Bone health; Gilthead seabream (Sparus aurata) larvae; Copper requirement
• ISSN: 0044-8486; 1873-5622
• DOI: 10.1016/j.aquaculture.2023.739319

The effect of dietary copper (Cu) levels on growth, oxidative stress, fatty acid profile and bone health of gilthead seabream larvae (Sparus aurata) was studied in 47 days-post-hatching fish fed 4 experimental diets containing 17, 18, 19 and 25 mg Cu/kg diet. After 21 days of feeding, larval growth and survival were not affected by the dietary Cu levels. However, larvae fed the non-supplemented diet (17 mg Cu/kg) showed clear symptoms of Cu deficiency, including increased lipid peroxidation and reduced bone mineralization. Increased peroxidation risk caused a reduction in essential fatty acids and n-3 PUFA (polyunsaturated fatty acids) contents in whole body lipids, whereas the poor vertebral body mineralization in seabream larvae was related to a marked increase in abdominal vertebrae anomalies. On the contrary, dietary Cu supplementation raised whole-body contents in DHA, EPA and n-3 PUFA and reduced MUFA, TBARS and the incidence of severe, cranial, branchiostegal rays and abdominal vertebral anomalies. Polynomial regression models applied to all these parameters suggested optimum dietary Cu levels to be 21.5–22.6 mg/kg in gilthead seabream larvae microdiets supplemented with CuSO4.5H2O. These levels (21.5–22.6 mg/kg) are in the range of the Cu contents in copepods (12–38 mg/kg) and on the verge of the dietary levels authorized by EU Commission in feeds for cultured fish species (25 mg Cu/kg diet).
•Dietary Cu levels from 17 to 25 mg Cu/kg did not significantly affect seabream larvae growth performance.•The elevation of dietary Cu levels increased the whole-body contents in DHA, EPA and n-3 PUFA, and reduced lipid peroxidation and severe, cranial, branchiostegal rays and abdominal vertebral anomalies.•Non-supplemented diet (17 mg Cu/kg) negatively affected the larvae by increasing lipid peroxidation, delaying mineralization and causing a high prevalence of skeletal anomalies.•Polynomial regression models applied to all these parameters suggested optimum dietary Cu levels to be 21.5–22.6 mg/kg in gilthead seabream larvae  microdiets supplemented with CuSO4.5H2O.