AbstractsBiology & Animal Science

Acartia Bifilosa viability in freshwater aquacultures

by Heidi Charlotte Højgaard




Institution: Roskilde University
Department:
Year: 2014
Keywords: Acartia Bifilosa; Salinity; Aquaculture
Record ID: 1120099
Full text PDF: http://rudar.ruc.dk/handle/1800/15286


Abstract

Abstract A lot of research has been given to the use of copepods in saltwater aquacultures; however there is also a demand for freshwater fish that could also potentially benefit from being fed copepods. Acartia bifilosa is a robust species in regards to their salinity stress and are as such potential candidates to utilize in freshwater aquacultures if they are capable of hatching and surviving for long enough to allow the fish larvae to ingest them. Sediment from Umeå, Sweden, was investigated under the assumption that it contained eggs from A. bifilosa. The sediment was distributed into 6 different salinities (0, 1, 7, 15, 30 & 40ppt), with the salinity of 7 being the control, where the eggs were allowed to hatch and after approximately 3 days the number of nauplii was counted. The copepods from the sediment turned out to handle all salinities relatively well, with hatching and survival in all 6 salinities, the lowest survival was seen at the extremes (0, 1 and 40 ppt), with hatching success at around 20-30%, and the highest hatching rates were seen in between at approximately 80-90%. To confirm if the copepods in the sediment were truly A. bifilosa, some sediment was used to hatch copepods to use for the identification of potential species in the sediment. Two species turned up in the sediment, being the assumed Acartia bifilosa and Eutymora affinis, another common copepod in the baltic. The distribution of the two species was roughly 1 E. affinis for every 5 A. bifilosa. The results from this study indicate that Acartia bifilosa has the potential to be used in freshwater aquacultures assuming its nutritional values were acceptable, as it both hatches and survives in fresh water.