Effects of zinc and manganese sources on gilthead seabream (Sparus aurata) fingerlings

Abstract

The use of vegetable ingredients may alter the mineral balance of feeds for gilthead seabream (Sparus aurata) due to the differences in mineral composition between marine and vegetable ingredients. Whereas seabream fed low levels of zinc (Zn) and manganese (Mn) may present reduced growth and performance, as well as alterations in mineral deposition and oxidative stress resistance, information on the type of sources of these two minerals is almost inexistent. In the present study, vegetable meal and oil (VM/VO) based diets were formulated including the target minerals, zinc (Zn) and manganese (Mn) in two different delivery forms, oxides and chelated to amino acids. Gilthead seabream of 8 .2g were fed one of five different diets containing either non mineral supplementation, Zn and Mn oxides, amino acid chelates and their combinations. During the experimental period, fish fed Zn oxide presented higher growth, a higher deposition of protein and lower lipid contents in whole body, whereas there was an increase in whole body TBARs and up-regulation of CuZnsod in fish fed diets supplemented with amino acids chelated Zn.