BIOTIN 



Monkeys 



The symptoms of chronic biotin deficiency observed in monkeys 

 were a thinning of the fur and a gradual reduction in the colour of 

 the hair.^' These symptoms were cured or prevented by 20 /xg. of 

 biotin per day. Acute biotin deficiency was produced by feeding egg 

 white or by adding 3 % of succinylsulphathiazole to the diet ; both 

 conditions were relieved by administration of 20 /xg. of biotin per 

 day. 



Dogs 



Puppies fed a synthetic diet deficient in the vitamin B complex, 

 but supplemented with aneurine, riboflavine, nicotinic acid, pyridoxine, 

 pantothenic acid, inositol, ^-aminobenzoic acid and choline, developed 

 a progressive paralysis after 7^ to 48 weeks. A cure was effected in 

 a few hours by administration of 100 fig. of synthetic biotin per kg. 

 of body^^'eight.^^ 



Pigs 



Biotin deficiency was produced in pigs by feeding 30% of desic- 

 cated egg white in the diet. It was characterised by alopecia, spas- 

 ticity of the hind legs, cracks in the feet and dermatosis accompanied 

 by dryness, roughness and a brownish exudate. 



These symptoms could be prevented by intramuscular injection of 

 100 fig. of biotin daily into each pig.^^ The same symptoms were 

 produced by administration of phthalylsulphathiazole, although 

 sulphaguanidine had no effect. Biotin prevented the symptoms and 

 inositol largely alleviated them. 20 Pigs fed a diet containing all the 

 other members of the vitamin B complex showed no increased growth 

 when biotin was added to the diet. 



Cows 



The dairy calf required an exogenous supply of biotin, otherwise 

 paralysis of the hind quarters developed. This was curable by 

 bio tin. 2^ 



Fish 



Biotin was found to be necessary for young rainbow trout, an 

 anaemia developing in its absence.22 prom 0-005 to 0-025 "ig- per 

 100 g. of diet was necessary to prevent deficiency symptoms from 

 developing. 



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