Use of Spirulina (Arthrospira platensis) as protein source for the nutrition of juvenile tench (Tinca tinca)

Spirulina is a protein source that have a high potential in formulation of fish feeding, as tested by several authors. Spirulina, in contrast to other protein terrestrial plant source, such as soybean meal, does not contain anti nutritional or toxic factors. Its composition include several nutrients, like antioxidants, vitamins and essential fatty acids. In our study we tested the growing response of tench to the substitution of fish meal with spirulina meal, focusing also to the variation of fatty acid profile and to the antioxidant proprieties of spirulina, using the formation of DNA adducts 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodGuo) as an indicator of oxidatively generated DNA damage.The results of the present trial demonstrated that it is feasible partially to replace fish meal with spirulina meal in the diet of juvenile tench, although the fatty acids profile of fish resulted affected by the presence of Linoleic Acid, introduced by spirulina meal. Spirulina showed in vivo antioxidant capacity, since fish fed with the highest amount of spirulina presented the lowest DNA adduct formation. Spirulina could be a valuable and sustainable source of protein for aqua feed, taking into account the cost of this ingredient, which could decrease in near future.