Aquaponic system is a strategic alternative for healthy fish production in Egypt

Aquaponic system is a way of growing fish and plants in a closed water system. It has been recorded to be the farming system of the future all over the world. This is because its ability to produce fish with good health year-around with low cost and low water use. Furthermore, fish waste acts as plants’ nutrients while plants purify the water and as a result growing fish and plants complementary. However, the possibility of establishing this system in Egypt still needs further studies to be able to acquire the consumer’s trust. Especially that Egyptians prefer eating Nile fish because they believe that this is the healthiest. Therefore, the present study was performed to compare the biochemical, histopathological and molecular parameters of the liver tissue of tilapia ( Oreochromis niloticus ) grown in the aquaponic system with tilapia that grown either in a reference farm that has an intense biological water treatment or in Egypt’s Nile River. Moreover, the water they had grown in was chemically analyzed. The results showed that water pH, conductivity, total dissolved salts, salinity, chloride, alkalinity, ammonia, nitrate, nitrite, and sulphates were at the lowest level while dissolved oxygen was at the highest level in aquaponic water as compared to the reference and Nile water, respectively. Liver enzymes activities were with lowest levels in the aquaponic group in comparison with the reference and Nile groups, respectively. Interestingly, relative increase in the antioxidant defense enzymes such as glutathione, catalase, glutathione peroxidase and glutathione-S-transferase while relative decrease in the thiobarbituric acid reactive substances, the lipid oxidation products were determined in the aquaponic tilapia. Moreover, aquaponic liver showed almost normal histological architecture and its genes expression of the growth hormone and insulin-like growth factor 1 were the highest. In conclusion, aquaponic system could be used as a strategic alternative method for healthy fish production in Egypt.