The effects of pure microcystin LR and biomass of blue-green algae on blood indices of carp (Cyprinus carpio L.)

Abstract

The aim of this work was to find out how the administration of the Microcystin LR and the biomass of blue-green algae with known amount of the Microcystin LR to juvenile carp influences indices of the red blood cells and activities of plasma enzymes. The experimental fish were given either pure Microcystin LR or the biomass of blue-green algae with known amount of Microcystin LR. The administration of pure Microcystin LR at the dose of 400 μg per 1 kg of body mass was conducted intraperitoneally, the biomass was applied per os. Microcystin LR volume in single doses was 3, 300, 600 and 1200 μg per 1 kg of body mass. After 24 and 48 h blood was taken from fish by cardiac punction. The following indices of the blood were evaluated: the red blood cell count (RBC), haematocrit (PCV), haemoglobin (Hb), mean corpuscular haemoglobin concentration (MCHC), mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH). Activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) and total plasma proteins (TPP) were measured. Significant changes (p ≤ 0.05 or p ≤ 0.01) of RBC, PCV, Hb, MCV and MCH were found only after the application of the biomass of blue-green algae. These changes were usually within the physiological range of values variation or slightly under this range. The activities of ALT, AST and LDH were mostly increased after all forms of administrations. The rate of increase depended on the route of administration, character of the material and amount of the toxin. A highly significant increase (p ≤ 0.01) of the activities of ALT (60.07 ± 36.89 μkat · 1-1, control 2.98 ± 1.58 μkat ·1-1), AST (38.91 ± 15.51 μkat · 1-1, control 4.83 ± 3.47 μkat ·1-1) and LDH (303.2 ± 110.7 μkat · 1-1, control 10.4 ± 5.1 μkat · 1-1) was detected 24 h after i.p. administration of pure Microcystin LR. Significant (p ≤ 0.05) increase of the activities of ALT was detected after oral administration of 3, 300 and 600 μg of Microcystin LR per 1 kg of body mass, highly significant (p ≤ 0.01) increase was detected after oral administration of 1 200 μg. Significant (p ≤ 0.05) or highly significant (p ≤ 0.01) increase of the activities of AST and LDH was detected only after oral administration of 1 200 μg of Microcystin LR. These changes were above the range of the normal values variation. The volume of TPP was significantly decreased (p ≤ 0.01) only 48 h after the administration of pure Microcystin LR (19.38 ± 4.90 g ·1-1, control 30.68 ± 4.10 g · 1-1). This change was at the limit of the normal values variation. Our investigation found out the influence of the biomass of blue-green algae to indices of red blood cells and verified the influence of Microcystin LR and the biomass of blue-green algae to activities of plasma enzymes. Fish, cyanotoxins, erythrocytes, plasma enzymes, total plasma protein.