The use of wax spray beads (WSB) for iodine enrichment of Artemia sp. for use as a live food for zebrafish (Danio rerio) larvae Public Deposited

http://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/fn107148f

Descriptions

Attribute NameValues
Creator
Abstract or Summary
  • Dietary iodine may play an important role in the nutritional health of freshwater fish larvae. Artemia, commonly used for the culture of larval zebrafish (Danio rerio), contain low concentrations of iodine when compared with wild zooplankton. Water-soluble micronutrients, such as iodine, are difficult to deliver to Artemia due to rapid diffusion from microparticles. Several methods have been developed to deliver water-soluble nutrients to live prey and are reviewed in this thesis. Wax spray beads (WSB) have been shown to retain greater than 50% of water- soluble micronutrients after 1h suspension in seawater. In addition, WSB have been used to bioencapsulate oxytetracycline (OTC; a water-soluble antibiotic) within Artemia but have not been previously used for the enrichment of micronutrients. It is currently unknown whether iodine, in the form of potassium iodide (KI), encapsulated within WSB is available to fish larvae and, if so, whether increased dietary iodine has a nutritional effect on larval zebrafish. Inert markers can been used to estimate ingestion and retention rates of diets by target organisms or to estimate feed preferences of organisms fed on multiple diets. In our study, yttrium (III) oxide (Y₂O₃) was used as an inert marker of WSB to provide detailed information about enrichment processes. The objectives of this study were to: 1) evaluate the use of wax spray beads containing potassium iodide (KI WSB) and wax spray beads containing KI and Y₂O₃ (KI+Y WSB) for enrichment of Artemia with iodine; 2) evaluate the use of Y₂O₃ as an inert marker in feeding experiments with Artemia fed on WSB; 3) determine if zebrafish larvae were able to uptake iodine from KI WSB-enriched Artemia; 4) investigate the effects of KI WSB-enriched Artemia on the growth, survival and thyroid status of larval zebrafish; 5) determine if Artemia were a potential source of exogenous thyroid hormones (TH) for larval fish; and 6) determine if KI WSB had an effect on bacterial concentrations associated with Artemia. We found that Artemia enriched with KI+Y WSB had higher levels of iodine than Artemia enriched with potassium iodide (KI) delivered in aqueous solution. WSB concentrations and the time of enrichment had significant effects on iodine and yttrium concentrations in Artemia. Enrichment with KI+Y WSB resulted in iodine absorption into Artemia tissues suggesting that a portion of the enriched iodine would be available to predators. Our results indicate that Y₂O₃ was an effective inert marker of WSB and was highly useful when interpreting data from enrichment trials. Zebrafish fed Artemia enriched with KI WSB showed a ten-fold increase in total iodine levels and increased survival when compared with larvae fed unenriched Artemia. Thirty-eight day post fertilization zebrafish larvae fed iodine-enriched Artemia had lower epithelium to colloid (v:v) ratios when compared to those fed unenriched Artemia. Artemia metanauplii were found to contain significant levels of deiodinase and thyroid hormones. KI WSB had no effect on the levels of marine bacteria associated with Artemia. The results of this study indicated that iodine contained in KI WSB enriched Artemia was available to larval fish. It is also apparent that early stage zebrafish benefitted from increased levels of dietary iodine. In addition, Artemia may provide larval fish with significant levels of exogenous thyroid hormones and deiodinase.
Resource Type
Date Available
Date Copyright
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Academic Affiliation
Non-Academic Affiliation
Keyword
Subject
Rights Statement
Language
Replaces
Additional Information
  • description.provenance : Approved for entry into archive by Julie Kurtz(julie.kurtz@oregonstate.edu) on 2010-05-03T15:51:46Z (GMT) No. of bitstreams: 1 Hawkyard_thesis.pdf: 3230290 bytes, checksum: 0ffc7d6001dc56d96cc4dd60d9c86aa2 (MD5)
  • description.provenance : Approved for entry into archive by Laura Wilson(laura.wilson@oregonstate.edu) on 2010-05-04T15:35:02Z (GMT) No. of bitstreams: 1 Hawkyard_thesis.pdf: 3230290 bytes, checksum: 0ffc7d6001dc56d96cc4dd60d9c86aa2 (MD5)
  • description.provenance : Made available in DSpace on 2010-05-04T15:35:02Z (GMT). No. of bitstreams: 1 Hawkyard_thesis.pdf: 3230290 bytes, checksum: 0ffc7d6001dc56d96cc4dd60d9c86aa2 (MD5)
  • description.provenance : Submitted by Donald Hawkyard (hawkyard@onid.orst.edu) on 2010-04-30T22:37:09Z No. of bitstreams: 1 Hawkyard_thesis.pdf: 3230290 bytes, checksum: 0ffc7d6001dc56d96cc4dd60d9c86aa2 (MD5)

Relationships

Parents:

This work has no parents.

Last modified

Downloadable Content

Download PDF

Items