Scurvy These make up one of two major primate suborders, haplorrhini and this group includes humans. The strepsirrhini (non-tarsier prosimians) can make their own vitamin C, and these include lemurs, lorises, pottos, and galagos. Ascorbic acid is also not synthesized by at least two species of caviidae, the capybara and the guinea pig. There are known species of birds and fish that do not synthesize their own Vitamin C. All species that do not synthesize ascorbate require it in the diet. Deficiency causes scurvy in humans, and somewhat similar symptoms in other animals. Animals that can contract scurvy all lack the
Vitamin A deficiency and lymphocytes. Suppression of these result in a lack of immune reaction if pathogens become present in the body and consequently a greater susceptibility to incubation of disease. VAD and infections aggravate each other, so with infection, vitamin A levels are depleted, which in turn reduces intestinal absorption of vitamin A. Very often seen with VAD is protein energy malnutrition, in which the synthesis of retinol binding protein (RBP) is decreased, consequently the uptake of retinol is reduced. This leads to an inability to use any vitamin A present as the RBP is absent, so the retinol cannot be transported