Multi-effects of temperature and particle size on the filter-feeding rate of brine shrimp Artemia at different growth stages and densities

Abstract Brine shrimp Artemia is able to filter particulate substances non-selectively and continuously, which make it an useful experimental animal in aquatic toxicological study. In this study, the filter-feeding rate (FFR) of Artemia franciscana at different temperatures (20℃/25℃/30℃) and densities (20/40/75/100 ind./100 mL at two earlier growth stages; 5/10/20 ind./100 mL at two later growth stages) on three unicellular algae ( Chlorella vulgaris , Porphyridium purpureum , Phaeodactylum tricornutum ) and two sizes of polyethylene balls (30 µm and 50 µm) was determined at Artemia four growth stages. The results showed that the FFR was positively correlated with the ambient temperature and Artemia body length, while it was negatively correlated with the Artemia density and particle size, and one way ANOVA analysis showed that the above factors mostly had significant effects on FFR (P < 0.05). And the favorable filtration particle size of Artemia increased with its body length. The equation of FFR in function of temperature, Artemia body length and density, and particle size was obtained using multiple linear regression analysis: FFR = 0.487*BL + 0.067*T-0.01D-0.064PS-1.508 (R 2 = 0.513). Of these four variables, body length had the greatest effect on FFR, followed by ambient temperature and particle size, and Artemia density. The results of this study provide a valuable guidance for proper feeding in the controlled Artemia production and standardization of experimental protocol of ecotoxicity and fundamental Artemia research, as well as facilities the application of Artemia in aquaculture wastewater treatment.