Aflatoxin and its risk management in aquaculture

Seafood consumption is increased mainly due to its availability, nutritional value, health benefits, reasonable price in comparison to livestock and poultry and finally lack of fatal diseases such as BSE (bovine spongiform encephalopathy) and FMD (foot and mouth disease) risk. Food contamination with mycotoxins is a serious setback to animal health and performance with subsequent health issues to animal protein product consumers. Mycotoxins are secondary fungal metabolites with different chemical charactristics and physiological effects. It is estimated that 25% of the world's agricultural products are annually affected and practically become useless. Aflatoxins are a group of mycotoxins with carcinogenic and immunosuppressive effects. Aflatoxins can transfer to body through food/feed and also via inhalation. Human and animal food/feed ingredients are susceptible to fungal colonization and growth. Aflatoxins are mainly produced by fungi species such as Aspergillus flavus and A. parasiticus. They concentrate in various tissues including liver, kidney, immune system, genital organs, nervous system and gastrointestinal tract. Certainly, they are considerably accumulated in the liver, for instance the hepatic concenteration of aflatoxin would be 10 times higher that its mascular concentration. Various risk management approaches have been proposed to deal with mycotoxins expecially aflatoxin contamination of feed ingredients, mainly including at-harvest and post harvest managemnets. In at-harvest method mostly avoiding insect damage, choosing varieties resistant to fungal diseases and well-adapted to growing area and biological control are addressed. However, avoiding delayed harvest, avoiding grain kernel damage, grain sorting, managing temperature and humidity of silos and ozone treatment and etc. are mainly considered in post harvest management of feed ingredients . This review summarizes the management strategies for preventing the toxicity of aflatoxin in aquaculture along with reviewing existing literature on the toxicity of aflatoxin in aquaculture animal and other monogastric animals expecially poltury.