Salinity effects on growth of four Artemia franciscana (Kellogg, 1906) populations, cultured in laboratory conditions from Yucatan Peninsula

The aim of is study was to determine the growth performance of Mexican A. franciscana Yucatan Peninsula strains in different salinity tests. Four populations from different habitats were studied: Real de las Salinas (RSAL), Cancun (CAN), San Crisanto (CRIS) and Celestun (CEL). Nauplii from each population were inoculated in 200 L plastic tanks with 160 L of dissolved rock salt water at 40, 60, 80, 100 and 120 g L-1. The organisms were fed with Tetraselmis sp. and Pinnularia sp. microalgae (500 x 103 cells mL-1 water concentration) during the experiment period. Biometry length was measured to obtain absolute growth rate (AGR), instantaneous growth rate (IGR), and length gain (LG) values. Variance test (ANOVA) analysis was applied to determine the significant differences (P <0.05) between final length and growth rates of four populations. The total length range was 6.675-9.589 mm; AGR values ranged between 0.395 and 0.571 mm per day. IGR percentage range was 17.623-18.91% increase per day, and length range gain values were 6.277 to 9.130 mm. No significant difference was shown between 100 g L-1 salinity test and 120 gL-1 test, and then between CEL and RSAL strains.  The salinity variable showed high percentage (62 to 93%) in the salinity tests or significant strains (p<0.05). Yucatan Peninsula has several salt ponds with natural Artemia franciscana sources that can be used for aquaculture or aquarium industry. It is important to know growth performance of species in specific salinity concentration. This will help one to understand the adaptation of Artemia populations cultured in laboratory and also ensure better culture system management for producing biomass for use in aquaculture or aquarium industry or academic laboratory centers.   Key words: Artemia franciscana, survival, growth rates, length gain, salinity.