CONICET | Buscador de Institutos y Recursos Humanos

ver pág 158 del CD de resúmenesNeocaridina heteropoda or ?red cherry? is a freshwater omnivorous shrimp with commercial potential as an ornamental species. The current study was aimed at evaluating the contribution of biofilm associated with different substrates on N. heteropoda culture. The experiment was run outdoors for 60-d in a zero water exchange system using plastic tanks filled with 20 L of aerated dechlorinated water, stocked with 174 adults shrimps/m2. Three substrates were tested: (PET) plastic bottles, (PN) plastic net (1 mm mesh size) and (AV) agrovelo (non-woven tissue). Ammonium, nitrite and nitrate concentrations were monitored weekly. Biofilm dry weight, chlorophyll a concentration and microorganisms were recorded bimonthly. Initially, chlorophyll a decreased in all treatments, but it increased afterwards. Biofilm dry weight was significantly higher in AV throughout the experiment. The main micro-organisms identified were: chlorophytas, pennate diatoms, cyanobacterias, flagellates, ciliates, rotifers and nematodes; both micro-organism diversity and abundance were higher in AV. Low levels of nitrogen compounds, high shrimp survival and growth and ovigerous females were observed in all groups. Both adults and juveniles actively grazed on the three substrates. The incorporation of biofilm in a zero water exchange system seems to represent an advantage for N. heteropoda culture, since it is involved in nutrient recycling and water quality improvement, and it may be an alternative natural and low cost food source. The three tested substrates were appropriated for biofilm growth.However, the use of recycled materials (such as PET) is more advantageous since it may reduce the environmental impact and production costs.UBACYT 2011-2014 (20020100100003)