Diet, carotenoids and oxidative balance in four penguin species: an interspecific comparison

COLOMINAS-CIURÓ R.; CARABAJAL E.; D'AMICO V.L.; BERTELLOTTI M.; BENZAL J.; VIDAL V.; MOTAS M.; CORIA N.; BARBOSA A.

Ciudad del Cabo

Congreso; 9th International Penguins Congress; 2016

Nutrition influences the physiology of the organisms in several ways. The diet is a source of antioxidantsthat mitigate reactive oxygen species (ROS) damage. ROS are produced by normal metabolic activities (e.g.aerobic cell respiration) and, according to the free radical theory, damage biomolecules (e.g. lipids, proteinsand DNA) unless quashed by antioxidants. Therefore, the disturbance in the pro-oxidant-antioxidantbalance in favour of the former leads oxidative stress. Dietary antioxidants (e.g. vitamins and carotenoids)perform a main role in the whole antioxidant network and, for example, because of the impossibility tosynthesis carotenoids by the birds, its efficiency may thus be affected by its diet. Krill is a main prey item forAntarctic Pygoscelis penguins: 70% (P. papua), 86% (P. antarcticus), 99.9% (P. adeliae) of the whole diet. Itis rich in astaxanthin which has antioxidative properties being more active than other carotenoids. Incontrast, Magellanic penguin (S. magellanicus) currently studied at Valdés Peninsula, account for 90 ormore percent of anchovies (E. anchoita) in its diet. Quantification of ROS, oxidative damage and antioxidantcapacity has attracted the attention to understand inter and intraspecific life-history variations. Hence,comparisons between species, sexes, populations, etc. are necessary. Our goal is to study the relationshipsbetween the diet, carotenoid concentration and oxidative stress. Diet was determined by means of stableisotope analyses, carotenoid concentration was determined by HPLC analyses and oxidative stress wasaccounted by analysing the oxidative damage (ROM) and the antioxidant capacity (OXY). Our resultspointed out interspecific differences and that diet as showed by the trophic level could influence oxidativestress and the antioxidant defences.