\. KFl'KC'IS OK DKl-'lCIKNCV GUI 



or e\(Mi jiniy.-' ■^- ^' ' Excoriations heal slowly. CutaiuMXis abscesses arc rare, 

 and wluMi jiresent they are ectliynia-like. Mild, sul)lin{>;ual ulcers are fairly 

 coniinoii. A spastic ^ait and a kanjiaroo-like posture,'* due probably to 

 hypertonicity of the striated muscles'-'^ paiticulaiiy of the hind legs, are 

 characteristic symjitonis of egg white injury in the ach'anced stage. ]3iotin 

 deficiency in rats may cause retention of tiie testes in the abdomen and 

 even a return of the already descended oi-gans to the alxlomen, owing to 

 the contracture of the cremaster muscle.'" 



i^iotin is needed for successful gestation and is piobably a necessary 

 factor in lactation botli in rats" and in mice.'- 



The skin lesions of biotin deficiency become more severe on low-fat 

 rations than on diets containing 18% of butterfat or hydrogenated cotton- 

 seed oil or 0.2 ml. of linseed oil.^ 



Biotin dehciency of a minor degree (combined with manifestations of 

 folic acid deficiency) may also be induced in the rat by feeding of sulfon- 

 amide-containing purified rations (p. 588). '^"^^ No acceleration or aggrava- 

 tion of biotin deficiency was obser\ed when succinylsulfathiazole was added 

 to a diet containing egg white.'** 



Biotin deficiency in black mice is characterized by depigmentation of the 

 fur and alopecia but not so much by scaly dermatitis. ''•*"-' 



The manifestations of biotin deficiency in rats and mice may be cured 

 in 2 to 4 weeks by the administration of biotin or food products containing 

 biotin. Severe skin lesions reciuire a prolonged period of treatment. Depig- 

 mentation of the fur may not completely respond to biotin.^ 



There appears to be a connection between biotin deficiency and panto- 

 thenic acid deficiency, and the depigmentation of fur first recognized in 

 deficiency of pantothenic acid''' --• --"• -* ma}" be the outward sign of such an 



* M. Sullivan and J. Xicholls, Arch. Dermatol, and Si/philol . 45, 295 (1942). 



9 G. A. Emerson and J. C. Keresztcsy, Proc. Sue. Expll. liial. Mrd. 51, 358 (1942). 

 '« W. K. Manning, Science 112, 89 (1950). 

 '> (\ Kennedy and L. S. Palmer, Arch. Riochem. 7, 9 (1945). 

 '2 L. Mirone and L. R. Cerecedo, Arch. Biochem. 15, 324 (1947). 

 '3 F. S. Daft, L. L. Ashburn, and W. H. Sebrell, Science 96, 321 (1942). 

 " G. J. Martin, Proc. Exptl. Biol. Med. 51, 353 (1942). 

 '^ E. Nielsen and C. A. Elvehjem, /. Biol. Chem. 145, 713 (1942). 

 '« F. \V. Heumann, M. M. Kiider. and II. G. Day, Proc. Soc. Expll. Biol. }ftd. 52, 



257 (1943). 

 >" A. D. Welch and L. D. Wright, J. Xuirition 25, 555 (1943). 

 i'* G. A. Emerson and E. Wurtz, Proc. Soc. Exptl. Biol. Med. 57, 47 (1944). 

 '9 1>. GyOrgy and C. E. Poling, Proc. Soc. Exptl. Biol. M,d. 45. 773 (1940). 

 2» E. Nielsen and A. Black, ./. Nutrition 28, 203 (1944). 



21 J. W. Wilson, E. H. Leduc, and D. H. Winston, /. \ntriii<ni 38, 73 (1949). 

 " P. Gyorgy and C. E. Poling, Science 92, 202 (1940). 



22" P. Gyorgy. C. E. Poling, and Y. Suhhaliow, ./. Biol. Chem. 132. 789 (1940). 

 23 K. Unna, G. V. Rich.-irds, and W. E. Sampson, ./. Xutritinn 22, 5.53 (1941). 



