Furthermore, injuries found in the liver and kidney of the birds days later showed the toxic action of microcystine. Although assessed total microcystines concentration was low, Chl-a concentration during the peak of mortality was much higher, revealing that toxicity may vary in the same strain, in the same water body and even during the same bloom (De Leon, 2002).
The most usually detected hepatotoxin is microcystine, which acts as an inhibitor of protein phosphatase 1 and 2A (Chorus and Bartram, 1999).
Samples were taken in order to identify algal species, Chl-a concentration (spectrophotometry) and toxins-total microcystines (inmuno-enzymatic assay, ELISA).
Maximal value of total microcystines concentration was 0.23 [micro]g.[L.sup.-1].