External and internal parasites and diseases such as Hepatosplentitis infectiosa strigum, pneumonia and tuberculosis are the most common ailments for owls, states Carolina Biological Supply Company. A protozoan parasite common in pigeons sometimes proves dangerous to owls, as well.Continue Reading
Feather lice are a common external parasite of owls, as are fleas and flies, notes Carolina Biological Supply Company. The latter two, however, are more interested in decaying organic material in owl nests than parasitizing the birds themselves. Because of their carnivorous diet, owls are also susceptible to internal parasitic worms.
Hepatosplentitis infectiosa strigum is a potentially fatal viral infection in owls, although barn owls and a few other species appear to be immune, states Carolina Biological Supply Company. The virus causes inflammation of the liver and spleen, notes Dictionary.com.
Owls that prey upon pigeons are at risk from a parasitic protozoan carried by some birds, explains Carolina Biological Supply Company. It causes a deposit to to develop in owls' throats, blocking the airway.Learn more about Owls