Vitamin C deficiency in growing willow ptarmigan (Lagopus lagopus lagopus)
Hanssen, I.; Grav, H.J.; Steen, J.B.; Lysnes, H.
Journal of Nutrition 109(12): 2260-2276
1979
ISSN/ISBN: 0022-3166 PMID: 512712 Document Number: 149987
Willow ptarmigan chicks raised on a diet containing 265 mg ascorbic acid/kg developed scurvy-like symptoms and died by 4 weeks of age. When blueberry plants were given freely as a supplement to the diet, the malady was prevented. The authors described the clinical, pathological and histological changes which accompany this malnutrition and concluded that they are in accord with the description of scurvy in guineapig and man. Biochemical measurement of ascorbic acid synthesis in the kidney of ptarmigan chicks indicated a rate of synthesis five times that found in livers of growing white rats. Blueberry plants and many other plants found in the natural diet of ptarmigan chicks contain ascorbic acid 2000 to 5000 mg/kg dry weight. Feeding experiments showed that the pathological signs were avoided and that already afflicted chicks recovered if the vitamin C content of the diet was raised to 750 mg/kg dry weight. Since the food intake of the chicks was 5 to 8 g/day the daily requirement of exogenous vitamin C was about 150 mg/kg bodyweight. This is an example of an animal which, while producing vitamin C itself, requires substantial amounts of external vitamin C to survive.