Indian fruit bat

Until the 20th century, it was thought that scurvy was confined to humans. Most plants and animals have the ability to synthesize ascorbic acid, but it was discovered that a limited number of animals, including primates, guinea pigs, the Indian fruit bat, and trout, also lack the ability to produce ascorbic acid. In vertebrates, ascorbic acid is made in the fiver from glucose in a four-step process. Each step requires a specific enzyme and humans lack the enzyme required for the last step, gulonolactone oxidase. 

Although most animal species can synthesize vitamin C, humans, guinea pigs, the Indian fruit bat, and the bulbul bird must obtain this vitamin from dietary sources. Citrus fruits, strawberries, tomatoes, and sweet potatoes are all excellent sources of vitamin C. 

Only man (and other primates), guinea-pigs, the Indian fruit bat and the red-vented bulbul (a bird) get scurvy other animals are able to synthesise ascorbic acid for themselves. 

The Indian fruit bat is also lacking in the liver enzyme for ascorbic acid synthesis (C6), but no nutritional studies have been reported. 

Ascorbic acid differs from the other vitamins in that it is required in the diet by only a few species of animals—man, other primates, the guinea pig, an Indian fruit-eating bat, and the red-vented bulbul and some related species of Pas-seriform birds. Other species of animals synthesize ascorbic acid. All mammals and other larger animals require vitamin A, thiamine, riboflavin, nicotinic acid, and pyridoxine as essential nutrients, although microoi anisms usually have the power to synthesize all or most of these substances. 

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