this symptoms caused by a protozoan (Histomonas meleagridis),and the disease called(Blackhead or Histomoniasis) is characterized by increased thirst, decreased appetite, watery sulfurcolored droppings, drowsiness, weakness, dry-ruffled feathers, dark cyanotic head, and lesions in the liver and ceca. Mortality is high, especially in poults less than 12 weeks of age. Histomonads are very stable inside cecal worm eggs that are ingested by earthworms. Earthworms can carry over the protozoans to successive broods year after year,Birds are infected with the protozoan by directly ingesting cecal worm eggs in the soil or indirectly ingesting the eggs through earthworms infected with the protozoans. When eaten, the birds release the protozoans by excreting them in feces. The protozoans together with E.coli and other intestinal bacteria produce the disease. Turkeys, chickens.