Frontiers in Marine Science (May 2014)
</center>SEABIOPLAS project <br />Seaweed co-products as micro-additives in fish feed</center> <br />
Abstract
SEABIOPLAS - SEAweeds from sustainable aquaculture as feedstock for biodegradable BIOPLAStics - is an ongoing FP7-funded European project which aims to introduce sustainably cultivated seaweeds as feedstock for biodegradable bioplastics. SEABIOPLAS is co-ordinated by Daithi O’Murchu Marine Research Station (DOMMRS), Ireland, with 11 partners in total, including a Portuguese SME (Algaplus). Europe produced 57 million tonnes of plastics in 2010, with the majority (39%) being used in the packaging sector. Currently, the production of bio-polymers is based on the use of important food resources for human and animal nutrition (e.g. corn, wheat, sugar beet and sugar cane). With the production of bioplastics expected to rise, the use of these crops as biopolymer sources will also increase, thus competing with food and energy production. SEABIOPLAS proposes to develop biopolymers from seaweed produced in Integrated Multi Trophic Aquaculture (IMTA) systems, creating greener plastics and valorizing seaweed residues as ingredients for animal feeds. The role of the CIIMAR team in the project is to study the use of seaweeds and their extracts in fish nutrition. Several variables, such as zootecnical parameters, metabolic and digestive enzymes, as well as stress and immune response parameters will be used as indicators of growth performance, fish health and welfare conditions. To do so, several feeding trials will be carried out under controlled rearing conditions, where biotic and abiotic factors will be used as stressors to determine the protective effects of seaweed supplementation in fish diets. Juvenile European seabass, Dicentrarchus labrax, will be used as the fish model, in a fast growing stage (IBW: 15-50 g). Each dietary treatment (control diet vs. experimental diets) will be fed in triplicate groups for approximately 90 days, twice a day to apparent satiety. Fish will be individually marked with Passive Integrated Transponder (PIT) tag prior to the beginning of the trials for monitoring individual fish performance. During the trials, samplings will be carried out at different times for determination the effects of treatment duration on the results. Growth performance will be determined by means of growth rate (% body weight/day); feed conversion ratio (FCR); voluntary fed intake (VFI, % body weight/day); protein efficiency ratio (PER); nutrient retention efficiency (%). To evaluate fish health and welfare condition, several stress biomarkers will be determine, such as glutathione-S-transferase (GST), catalase (CAT), superoxide dismutase (SOD), lipid peroxidation (LP), oxidized protein (POx); Acetylcholinesterase (AChE), and glutathione peroxidase (GPx). In addition, gross morphometric indices: such as the condition factor (K) and hepato-somatic index (HSI) will be calculated as auxiliary indicators of health status and liver condition of fish. For immune parameters, plasma for humoral analyses parameters will be used (peroxidase, lysozyme activity, alternative complement activity and superoxide anion production).
Keywords
