Plasmodium berghei malaria. Light micrograph of the blood smear of a mouse, showing gametocytes of the malaria parasite Plasmodium berghei. Red blood cells appear grey. The malaria parasites are stained blue/purple here, and appear elongated in shape. As in humans, this species of malaria which infects mice is transmitted by a blood-sucking insect. In the bloodstream the parasite enters the liver where it reproduces and releases merozoites that enter the red blood cells where further growth and multiplication occurs. Affected red blood cells are destroyed by the parasites and the host animal becomes anaemic, suffering from recurrent fevers. Magnification x327 at 35mm size.