Enrichment of Chironomid Larvae with Ascorbic Acid

Abstract

Due to the importance of ascorbic acid (AA) in fish larval development and performance, chironomid (midge) larva were enhanced with AA using chicken manure mixed thoroughly with a stable form of ascorbic acid (L-ascorbyl-2-polyphosphate). AA was used in three doses (0, 100, and 1,000 mg/kg) each with three replicates. The chironomid culture was maintained for 18 days. There were no significant differences (P > 0.05) in average biomass and growth of chironomid larva among the treatments. Spectrophotometric analysis of AA content of chironomids demonstrated that 1,000 mg/kg produced larvae with significantly (P < 0.05) higher AA content (779.86 ± 31.81 μg/g) than 0 (74.2 ± 15.45 μg/g) or 100 mg/kg (325.03 ± 116.61 μg/g). This result indicated that using chicken manure as substrate mixed by high doses of stable form of AA is an efficient method of enriching and enhancing the nutritional value of this kind of live feed.

KEYWORDS:

• Bloodworm
• mass production
• ascorbic acid
• enrichment

ACKNOWLEDGMENTS

The authors are indebted to Dr. J. Fattahi Moghadam, M. Kia Eshkevariyan, and M. Alipour at the Iran Citrus Research Institute for their assistance in vitamin C analysis. Special thanks to Dr. Y. Hamidoghli and S. R. Akhavan for their helpful advice during the project.