Survey on feed quality of Rainbow Trout (Oncorhynchus mykiss) in fish farms of Fars Province

This study was carried out to evaluate the qualitative status of chemical analysis including moisture, crude protein, crude ash, crude fat, NDF, (Insoluble fibers in neutral detergent) and ADF. (Insoluble fibers in acidic detergent), and the possibility of aflatoxin and mold contamination in fattening salmon feed used in fish farms in Fars province and fish feed supply factories. The obtained data were analyzed using SPSS software and Duncan test was used to compare the means of the data. The results showed that crude protein in feed GFT1 and GFT2 of factory No.2 had statistically significant difference (P<0.05) from other three factories. Only feed of a factory No. 2 provides the minimum amount of crude protein required for fish in these groups. The amount of crude protein in GFT3 and GFT4 related to factories 2 and 3 higher than that in factories 1 and 4 (p<0.05), but all factories have the minimum amount of crude protein needed by this group. The results of contamination of all samples of forage feed (GFT1, GFT2, GFT3, and GFT4) of fish farms and factories to aflatoxins and mold showed that the contamination rate is lower than the standard. In general, due to the different chemical composition of feed samples in fish farms, different feed supply factories and failure to meet the needs of fish at different ages, it is mandatory to continuous monitoring of feed produced in different factories and providing corrective guidelines to improve nutritional status of fattening fish.