Survival and growth rate of Perinereis rullieri (Polychaeta, Nereididae) under different salinities and diets

The effects of salinity and diet on survival and growth rate of the nereidid polychaete Perinereis rullieri have been investigated under controlled laboratory conditions. The experiment began from nec nectochaetes at 5-6 setigerous segments to exclude the high mortality occurring immediately after hatching. The tested salinities were 10 - 20 - 30 and 40 parts per thousand that slightly exceed those recorded in the natural environment during larval emergence. The larvae were fed with Tetramin MicroMin dry fish food and Tetramin MicroMin added with freeze-dried lyophilised Ulva rigida to test the possible antistress effect of vitamins C and E, in which the alga is rich. The experimental results highlight the influence of salinity on survival and growth race of P. rullieri. Enrichment with alga does not significantly affect survivorship and growth rates under all experimental conditions.