Effects of formaldehyde preservation on biometrical characters, biomass and biochemical composition of Acartia clausi (Copepoda, Calanoida)

Abstract

The effects of formaldehyde preservation on biometrical characters, biomass and biochemical composition of the marine copepod Acartia clausi were studied using the relevant values of fresh unpreserved animals as reference. Acartia were collected in the southern parts of Saronicos Gulf in early May (16.5°C) and late June (21°C). Formalin was found to cause significant shrinkage of cephalothorax length, abdomen length and total length. The sex of individuals, as well as the temperature of seawater at the time of collection seem to influence dimensional losses. Females and animals collected at 16.5°C presented heavier losses. Dry weight is drastically reduced after formaldehyde preservation. Final losses are more severe for females and animals collected at 21°C. Two of the measured biochemical constituents, carbohydrates and neutral lipids, seem to be unaffected by formaldehyde. DNA and RNA although initially affected seem to be stabilized towards the end of the experimental period (30 days). The other biochemical parameters, viz proteins, total lipids and sugars, are profoundly affected by preservation.