Effect of pre- and probiotics on hatching of Acartia tonsa

Acartia tonsa eggs (provided from CFEED.no, stored at 5°C) were incubated 48h at 20°C in 4 treatments: control, prebiotic (scFOS, 5 mg/L), probiotic (bacillus, 100 mg/L) and synbiotic (scFOS 5 mg/L, bacillus 100 mg/L), in time separated replicates. Egg density was 15 eggs/mL in 20L tanks. Rhodomonas baltica (provided from CFEED.no) were fed from 24h onwards. Hatching success was monitored at 48h. Nauplii were sieved off (40 µm) and collected for fatty acid analysis. Samples for bacterial flow cytometry were taken from the different algae stocks used for each replicate experimental run. Algae density in the stock was 15 million cells rhodomonas/mL. Samples for bacterial flow cytometry were taken from the incubation tanks at various time points during incubation. Flow cytometry was performed by kytos (kytos.be). The corresponding manuscript is available on biblio.ugent.be (Ghent University)