Inclusion of grape bagasse ( Vitis sp. ) in the diet of white shrimp ( Litopenaeus vannamei ) and its effects on growth and antioxidant system

Abstract

Innovation in aquaculture nutrition is linked to the use of new compounds, in order to achieve a more sustainable production. The grapefruit industry is one of the biggest in the fruit sector due to the enormous wine and juice production. As a consequence, tons of grape bagasse (GB) turn into waste every year, a product rich in antioxidants such as polyphenols (PPS). Shrimp Litopenaeus vannamei is generally cultured under stressful conditions such as crowding, which can increase the production of reactive oxygen species (ROS) and could benefit from feed with functional properties. Five isoproteic and isolipidic diets were formulated: GB0, GB2.5, GB5, GB10 and GB15% of GB inclusion; those diets were tested in triplicate. Shrimp juveniles (0.35 ± 0.01 g) were stocked at a density of 150 shrimp m−3, and fed for 45 days. At the end of the experimental period, hepatopancreas and muscle samples of shrimp were collected for the determination of the antioxidant capacity against peroxyl radicals (ACAP), thiobarbituric acid-reactive substances (TBARS) and PPS content. The results indicate that it is possible to add up to 2.5% of GB inclusion without affecting growth and feed conversion rate significantly. Also, the shrimps muscle of the GB15 treatment presented the highest PPS concentration and the lowest lipid peroxidation. In conclusion, it is possible to include GB in shrimp diets in small amounts, despite not obtaining significant antioxidant benefits.