The loss rates of protein and lipids were determined for enriched Artemia franciscana starved at different temperatures after enrichment. Following 12-h enrichment with DHA Selco (0.2 g l−1) at 28°C, the nauplii were temperature acclimated and transferred to starving condition (0–96 h; 5°C to 30°C).
The total lipid content during enrichment increased from 145 mg g−1 dry weight (DW) (newly hatched nauplii) to 222 mg g−1 DW after 12 h. The DHA/EPA ratio reached an optimum after 12 h (1.85), where DHA and EPA constituted 12% and 6.7% of total fatty acids, respectively.
When the nauplii were transferred to starving conditions the contents of all lipid components became reduced. The specific loss rate was found to be exponential for all components and significantly higher for DHA than for EPA and the sum of the other n−3 fatty acids. A. franciscana starved at the highest temperature (30°C) showed a loss rate of 92% day−1 (of DHA). Nauplii starved at 12°C had a loss rate of 51% day−1 (of DHA). At the same temperature (12°C) the corresponding loss rate of EPA, the sum of the other n−3 fatty acids and for the total lipid content was 15%, 30% and 11% day−1, respectively.
The protein content was relatively stable in the nauplii kept at the lowest temperatures (5°C and 8°C), but as temperature increased, the loss rate of protein gradually increased reaching a loss rate of 28% day−1 in nauplii starved at 26°C. The survival of the nauplii was >67% throughout the starvation period (96 h), but at temperatures below 8°C and above 19°C, the survival was