Carotenoid feed supplementation in argentine penaeoid shrimp broodstock

Abstract

This work aimed to improve reproductive maturation in two penaeoid species (Artemesia longinaris and Pleoticus muelleri) by using carotenes added in artificial feeds and comparing antioxidant activity and carotenoids profiles. Immature females were kept for 45 days at salinity 33, temperature at 18°C, pH 7, 12:12 h photoperiod, ammonium <0.2mg L-1 and seawater exchanged at 100% per day. Feeding regimes consisted of 50% fresh frozen ingredients (clam muscle and squid mantle) and 50% dry pellets. For each species, three pelletized feeds were tested, one as a control (C) and two supplemented each one with 300 mg astaxanthin (A) and β-carotene (B) kg-1 of diet. At the end of the trials, ovaries, midgut gland, and integument were sampled. In both species, the addition of carotenoids improved ovarian development: 100% of females fed A or B diets were mature, but of the females fed with diet C only 75% (P. muelleri) and 64% (A. longinaris) matured. Ovaries of mature females exhibited the highest concentration of carotenoids. The abundance of free astaxanthin regarding total carotenes, suggests that excess of free astaxanthin could be biotransformed to esterified astaxanthin. The scavenging properties were evaluated against the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical by electron resonance spectroscopy (EPR). For all feed treatments, the extracts exhibited strong DPPH scavenging activity, without significant differences among them.