Photoprotective effect of invasive kelp Undaria pinnatifida extract as feed additive on prawn Palaemon macrodactylus from the Argentine coast

Abstract

In the present study, adult individuals of Palaemon macrodactylus were fed Undaria pinnatifida extract and exposed to ultraviolet radiation (UVR) to determine the bioaccumulation of photoprotective compounds and their potential photoprotective effect. Animals (0.25 ± 0.09 g) were fed for 40 days as follows: control feed (C) and control feed added with 2% of U. pinnatifida extract (U2). After the feeding experiment, animals were subjected to two radiation treatments: photosynthetically active radiation 400–700 nm (PAR) and PAR + UVR (280–700 nm). At the end of the feeding experiment, the weight gain and survival percentage were similar in both treatments, and UV-absorbing compounds were found only in animals fed U2. Regarding exposure to UVR, survival was significantly higher in animals fed U2 than in those fed the control diet. Our results indicated that the adult prawn P. macrodactylus can accumulate photoprotective compounds from its diet, thus building strong resistance to UVR.