Dietary biology of the Eurasian eagle-owl but none are heavier than the largest mammalian prey that eagle-owls have taken including greater white-fronted goose ("Anser albifrons"), bar-headed goose ("Anser indicus"), great cormorant ("Phalacrocorax carbo"), Himalayan snowcock ("Tetraogallus himalayensis") and demoiselle crane ("Anthropoides virgo"), all averaging around , the swan goose ("Anser cygnoides"), the common crane ("Grus grus") and the (between the dimorphic sexes) great bustard ("Otis tarda"). Eurasian eagle-owls have also hunted adult male western capercaillie, which average about , although usually the much smaller females, at , are more regularly taken. Although they rarely take domestic birds, the range of sizes killed is just as dramatic,
Porphyria cutanea tarda the body. Certain mutations in the "HFE" gene cause hemochromatosis (an iron overload disorder). People who have these mutations are also at an increased risk of developing porphyria cutanea tarda. In the 20% of cases where porphyria cutanea tarda is inherited, it is inherited in an autosomal dominant pattern, which means one copy of the altered gene is sufficient to decrease enzyme activity and cause the signs and symptoms of the disorder. While inherited deficiencies in uroporphyrinogen decarboxylase often lead to the development of PCT, there are a number of risk factors that can both cause and exacerbate the symptoms