Blue-green algae toxicosis in cattle

Microcystin-LR is a cyclic heptapeptide produced by blue-green algae (Microcystis spp) and can induce acute, potentially lethal hepatotoxicosis in mammals and birds. Blue-green algae toxicosis should be considered in animals with histologic evidence of intrahepatic hemorrhage, hepatic enlargement, and disassociation and necrosis of hepatocytes. High-pressure liquid chromatography of water and ingesta for microcystin-LR can be used to establish a definitive diagnosis of blue-green algae toxicosis.