Proximate composition and heavy metal analyses of commercial fish feeds in Nigeria

Abstract

Fingerling, juvenile and grower fish feeds (imported and locally produced) were obtained and proximate analysis was done to determine moisture content, ash content, crude fibre content, crude fat content, crude protein content and carbohydrate content. Results revealed that locally grower (LG) feed have higher moisture and carbohydrate content and the least crude protein and fat content. According to the results obtained, glutamic acid was the most abundant followed by aspartic acid, leucine, arginine, phenylalanine, lysine, valine and proline. All the amino acid content of Imported fingerling (IF) and juvenile (IJ) feeds are higher than the amino acid content of Imported and local grower (IG, LG) feeds. . Mineral content in increasing order of all the samples in mg/kg of feeds are as follows: Fe (67.20 - 93.99): IG >IF>LG>IJ; Cu (8.29 – 13.61): IJ>IG>IF>LG; Mn (48.02 –82.78): IJ>LG>IG>IF; Zn (122.30 – 146.27): IF>IJ=IG>LG; Se (0.227 – 0.672): LG>IF>IG>IJ; Cr (0.457 – 1.120): LG>IF>IJ>IG; Cd (0.224 – 0.490): IF>IJ>LG (IGND); Ni (0.229 – 0.245): LG>IF>IG (IJ- ND). Cobolt was not detected in all the feeds while 1.12 mg/kg feeds Lead was detected in locally produced grower feed only.

Key words: Fish-feed, proximate analysis, amino-acid, mineral content, statistical analysis