Iodine nutrition and toxicity in Atlantic cod (Gadus morhua) larvae
Copepods as feed promote better growth and development in marine fish larvae than rotifers. However, unlike rotifers, copepods contain several minerals such as iodine (I), at potentially toxic levels. Iodine is an essential trace element and both under and over supply of I can inhibit the production...
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ftdoajarticles:oai:doaj.org/article:6d1900ea8c8448b4a4d0bbf644612369 2024-01-07T09:42:09+01:00 Iodine nutrition and toxicity in Atlantic cod (Gadus morhua) larvae S Penglase T Harboe Ø Sæle S Helland A Nordgreen K Hamre 2013-02-01T00:00:00Z https://doi.org/10.7717/peerj.20 https://doaj.org/article/6d1900ea8c8448b4a4d0bbf644612369 EN eng PeerJ Inc. https://peerj.com/articles/20.pdf https://peerj.com/articles/20/ https://doaj.org/toc/2167-8359 doi:10.7717/peerj.20 2167-8359 https://doaj.org/article/6d1900ea8c8448b4a4d0bbf644612369 PeerJ, Vol 1, p e20 (2013) Fish larvae Cod larvae Rotifers Iodine requirement Iodine toxicity Thyroid hormones Medicine R Biology (General) QH301-705.5 article 2013 ftdoajarticles https://doi.org/10.7717/peerj.20 2023-12-10T01:51:35Z Copepods as feed promote better growth and development in marine fish larvae than rotifers. However, unlike rotifers, copepods contain several minerals such as iodine (I), at potentially toxic levels. Iodine is an essential trace element and both under and over supply of I can inhibit the production of the I containing thyroid hormones. It is unknown whether marine fish larvae require copepod levels of I or if mechanisms are present that prevent I toxicity. In this study, larval Atlantic cod (Gadus morhua) were fed rotifers enriched to intermediate (26 mg I kg-1 dry weight; MI group) or copepod (129 mg I kg-1 DW; HI group) I levels and compared to cod larvae fed control rotifers (0.6 mg I kg-1 DW). Larval I concentrations were increased by 3 (MI) and 7 (HI) fold compared to controls during the rotifer feeding period. No differences in growth were observed, but the HI diet increased thyroid follicle colloid to epithelium ratios, and affected the essential element concentrations of larvae compared to the other groups. The thyroid follicle morphology in the HI larvae is typical of colloid goitre, a condition resulting from excessive I intake, even though whole body I levels were below those found previously in copepod fed cod larvae. This is the first observation of dietary induced I toxicity in fish, and suggests I toxicity may be determined to a greater extent by bioavailability and nutrient interactions than by total body I concentrations in fish larvae. Rotifers with 0.6 mg I kg-1 DW appeared sufficient to prevent gross signs of I deficiency in cod larvae reared with continuous water exchange, while modelling of cod larvae versus rotifer I levels suggests that optimum I levels in rotifers for cod larvae is 3.5 mg I kg-1 DW. Article in Journal/Newspaper atlantic cod Gadus morhua Copepods Rotifer Directory of Open Access Journals: DOAJ Articles PeerJ 1 e20 |
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Fish larvae Cod larvae Rotifers Iodine requirement Iodine toxicity Thyroid hormones Medicine R Biology (General) QH301-705.5 |
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Fish larvae Cod larvae Rotifers Iodine requirement Iodine toxicity Thyroid hormones Medicine R Biology (General) QH301-705.5 S Penglase T Harboe Ø Sæle S Helland A Nordgreen K Hamre Iodine nutrition and toxicity in Atlantic cod (Gadus morhua) larvae |
topic_facet |
Fish larvae Cod larvae Rotifers Iodine requirement Iodine toxicity Thyroid hormones Medicine R Biology (General) QH301-705.5 |
description |
Copepods as feed promote better growth and development in marine fish larvae than rotifers. However, unlike rotifers, copepods contain several minerals such as iodine (I), at potentially toxic levels. Iodine is an essential trace element and both under and over supply of I can inhibit the production of the I containing thyroid hormones. It is unknown whether marine fish larvae require copepod levels of I or if mechanisms are present that prevent I toxicity. In this study, larval Atlantic cod (Gadus morhua) were fed rotifers enriched to intermediate (26 mg I kg-1 dry weight; MI group) or copepod (129 mg I kg-1 DW; HI group) I levels and compared to cod larvae fed control rotifers (0.6 mg I kg-1 DW). Larval I concentrations were increased by 3 (MI) and 7 (HI) fold compared to controls during the rotifer feeding period. No differences in growth were observed, but the HI diet increased thyroid follicle colloid to epithelium ratios, and affected the essential element concentrations of larvae compared to the other groups. The thyroid follicle morphology in the HI larvae is typical of colloid goitre, a condition resulting from excessive I intake, even though whole body I levels were below those found previously in copepod fed cod larvae. This is the first observation of dietary induced I toxicity in fish, and suggests I toxicity may be determined to a greater extent by bioavailability and nutrient interactions than by total body I concentrations in fish larvae. Rotifers with 0.6 mg I kg-1 DW appeared sufficient to prevent gross signs of I deficiency in cod larvae reared with continuous water exchange, while modelling of cod larvae versus rotifer I levels suggests that optimum I levels in rotifers for cod larvae is 3.5 mg I kg-1 DW. |
format |
Article in Journal/Newspaper |
author |
S Penglase T Harboe Ø Sæle S Helland A Nordgreen K Hamre |
author_facet |
S Penglase T Harboe Ø Sæle S Helland A Nordgreen K Hamre |
author_sort |
S Penglase |
title |
Iodine nutrition and toxicity in Atlantic cod (Gadus morhua) larvae |
title_short |
Iodine nutrition and toxicity in Atlantic cod (Gadus morhua) larvae |
title_full |
Iodine nutrition and toxicity in Atlantic cod (Gadus morhua) larvae |
title_fullStr |
Iodine nutrition and toxicity in Atlantic cod (Gadus morhua) larvae |
title_full_unstemmed |
Iodine nutrition and toxicity in Atlantic cod (Gadus morhua) larvae |
title_sort |
iodine nutrition and toxicity in atlantic cod (gadus morhua) larvae |
publisher |
PeerJ Inc. |
publishDate |
2013 |
url |
https://doi.org/10.7717/peerj.20 https://doaj.org/article/6d1900ea8c8448b4a4d0bbf644612369 |
genre |
atlantic cod Gadus morhua Copepods Rotifer |
genre_facet |
atlantic cod Gadus morhua Copepods Rotifer |
op_source |
PeerJ, Vol 1, p e20 (2013) |
op_relation |
https://peerj.com/articles/20.pdf https://peerj.com/articles/20/ https://doaj.org/toc/2167-8359 doi:10.7717/peerj.20 2167-8359 https://doaj.org/article/6d1900ea8c8448b4a4d0bbf644612369 |
op_doi |
https://doi.org/10.7717/peerj.20 |
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