EFFECTS OF EXTRACTS OF BROWN SEAWEEDS AS DIETARY ADDITIVE ON THE METABOLIC PROFILE AND FEED DIGESTIBILITY IN Artemesia longinaris

MARÍA LAURA ESPINO; NATALIA SOLEDAD ARZOZ; ANA CRISTINA DÍAZ; SUSANA MARÍA VELURTAS; MARÍA ALEJANDRA MARCOVAL; JORGE LINO FENUCCI

Congreso; JOINT MEETING OF BIOSCIENCE SOCIETIES; 2017

A study was conducted to evaluate polysaccharide extracts ofbrown seaweeds as dietary additive for prawns (5.9±1.30g). Theaim of this study was to compare zootechnical parameters, metabolicprofile and apparent digestibility of Artemesia longinaris fed dietswith 0; 1 or 2g of polysaccharide extracts of Undaria pinnatifida orMacrocystis pyrifera (C, U1, U2, M1, and M2, respectively), and with0.5% Cr2O3 as inert marker. To determine apparent digestibility, feceswere collected during the last two weeks of the trial, and to measuremetabolic variables (glucose, triglycerides, cholesterol, totalproteins), haemolymph was extracted at the end of the experiment.After 30 days of feeding in all treatments, the survival was superiorto that considered as acceptable in commercial culture, percentagesvaried between 60% and 79.2% and no significant differences werefound between treatments. Percentage of increment in mean weightof prawns under different treatments varied between 8.5 and 16.7%,with higher values in animals fed with U. pinnatifida extract (U1 andU2). Apparent digestibility decreases significantly with the additionof 2g of both extracts, although this effect was lower in those animalsfeed U1 and U2. Regarding the determination of metabolites,no significant differences were found in levels of plasma metabolitesin animals feed with M. pyrifera but a significant increase wasobserved in total protein and cholesterol concentrations in animalsfeed with diet supplemented with 1g of U. pinnatifida. These resultssuggest that, the use of polysaccharide extracts of U. pinnatifida isfeasible as additive in diets for the prawn A. longinaris. The optimallevel of inclusion may vary depending on the algal species, forculture this species, the recommended concentration should be 1g,since it is the one that produces increase in mean weight, withoutinterfering with apparent digestibility.Keywords: Artemesia longinaris, seaweeds, apparent digestibility,metabolic profile.