Acta Vet. Brno 2010, 79: 63-71

Selected Haematological and Biochemical Indices of Nile Tilapia (Oreochromis niloticus) Reared in the Environment with Cyanobacterial Water Bloom

Miroslava Palíková1, Radovan Kopp2, Jan Mareš2, Stanislav Navrátil1, Zdenek Kubíček3, Lubomír Chmelař4, Hana Banďouchová1, Jiří Pikula1

1Department of Veterinary Ecology and Environmental Protection, University of Veterinary and Pharmaceutical Sciences Brno, Czech Republic,
2Department of Fishery and Hydrobiology, Mendel University of Agriculture and Forestry, Brno, Czech Republic,
3Department of Clinical Biochemistry, Hospital Trinec, Czech Republic,
4Medistat, Brno, Czech Republic

Received September 18, 2009
Accepted April 6, 2010

The aim of this study was to evaluate the influence of toxic cyanobacterial water blooms on blood indices in the Nile tilapia (Oreochromis niloticus). Experimental fish were exposed to natural cyanobacterial water blooms (consisting mainly of Microcystis aeruginosa and M. ichthyoblabe) which contained microcystins (total concentration 1187 - 1211 μg g-1 of dry weight and 17.4 - 25.4 μg l-1 of water) for 28 days without additional feeding. Control groups of fish were kept in another pond without apparent cyanobacterial bloom formation. Experimental and control rearing ponds had the same water source. After exposure, fish were placed in dechlorinated potable water for the same period. Statistical evaluation of the influence of cyanobacterial water bloom on biochemical indices of experimental fish showed a distinct increase of alkaline phosphatase (p ⪬ 0.05), total bilirubin (p ⪬ 0.001), creatinine (p ⪬ 0.01), lactate (p ⪬ 0.01) and urea (p ⪬ 0.01) when compared to controls. After transfer to the dechlorinated potable water the experimental group showed significantly lower values of phosphorus (p ⪬ 0.001), urea (p ⪬ 0.01) and cholinesterase (p ⪬ 0.05) and higher values of lactate (p ⪬ 0.05) and iron (p ⪬ 0.05) compared to controls. It may be concluded that the exposure of the Nile tilapia to the environment containing cyanobacterial water bloom influenced only some biochemical indices. However, this modulation is to a much lower degree compared to the common carp and silver carp.