Article

Effects of Microcystis cells, cell extracts and lipopolysaccharide on drinking and liver function in rainbow trout Oncorhynchus mykiss Walbaum.

Division of Environmental and Applied Biology, School of Life Sciences, University of Dundee, DD1 4HN Dundee, UK.
Aquatic Toxicology (impact factor: 3.76). 10/2003; 64(4):419-26. pp.419-26
Source: PubMed

ABSTRACT Liver mass (hepatosomatic index, HSI) increased by approximately 18% and water content in the gut by approximately 13 ml kg(-1) in freshwater rainbow trout exposed for 24 h to intact cells of a microcystin-producing cyanobacterium (Microcystis PCC 7813) together with administration of heterotrophic bacterial LPS. Exposure to broken (ultrasonicated) cyanobacterial cells together with administration of bacterial LPS increased HSI by approximately 50% and water content in the gut by almost 30 ml kg(-1). Exposure to broken or unbroken Microcystis cells without administration of bacterial LPS resulted in increased water content of the gut (by approximately 13 ml kg(-1)) with insignificant changes in HIS. Drinking rate increased with increasing dosage of bacterial LPS alone. The increased volume of water in the gut potentially increases the opportunity for uptake of waterborne toxins, including microcystins, and increased liver mass is a symptom consistent with the toxic effects of microcystins. It is concluded that exposure of fish to the cell contents of cyanobacteria (e.g. Microcystis PCC 7813) promotes osmoregulatory imbalance resulting from stimulation of the drinking response, increased volume of fluid in the gut and inability to remove excess water.

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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

bacterial LPS
 
cell contents
 
Drinking rate
 
drinking response
 
excess water
 
freshwater rainbow trout
 
hepatosomatic index
 
heterotrophic bacterial LPS
 
increased volume
 
insignificant changes
 
intact cells
 
liver mass
 
microcystin-producing cyanobacterium
 
Microcystis PCC 7813
 
symptom consistent
 
toxic effects
 
unbroken Microcystis cells
 
uptake
 
water content
 
waterborne toxins