XI. REQUIREMENTS AND FACTORS INFLUENCING THEM 685 



the diet of chicks influences the requirement of pantothenic acid; without 

 Bi2 it was reported as 2 mg. per 100 g. of diet, whereas with adequate B12 

 it was only 1 mg. per 100 g. of diet. Jukes, however, concluded from his 

 experiments'^^ that the requirement of chicks for pantothenic acid is not 

 significantly affected by the lack of B12 if the diet is adequate in methionine 

 and choline. In young pigs fed practical rations with only 1-4 % protein, 

 Catron et al.,^^" in 1953, also found a sparing action of vitamin B12 on the 

 pantothenic acid requirement. 



Wright and Welch^" reported that a relationship exists between defi- 

 ciencies of folic acid and biotin and the development of signs of pantothenic 

 acid deficiency. Following the administration of succinylsulfathiazole to 

 rats, changes appeared which were very similar to those seen in pantothenic 

 acid deficiency, and a low level of this vitamin in the liver was demonstrated. 

 Administration of additional pantothenic acid did not correct these condi- 

 tions in any way, but administration of folic acid and biotin corrected 

 them completely. These investigators interpreted their results as indicating 

 that deficiencies of folic acid and biotin prevent the proper utilization of 

 pantothenic acid. 



Daft^^ showed that the inclusion of ascorbic acid at a level of 2 % in diets 

 deficient in pantothenic acid prevented the development of the usual panto- 

 thenic acid deficiency syndrome in weanling rats. Daft and Schwarz^- re- 

 ported on these and similar experiments after the animals had remained 

 on the deficient diet for one year. Some rats grew to a weight of over 500 g. 

 during this period, having received from weaning a highly purified diet 

 with no supplementary pantothenic acid. Hvnidley and Ing"*-" showed that 

 glucuronolactone and other related compounds could successfully replace 

 ascorbic acid in similar experiments. Everson et al}'^^ reported that the in- 

 clusion of 2 % of ascorbic acid in a pantothenic acid-deficient diet had a 

 beneficial effect on reproduction. 



d. Effect of Antibiotics 



In 1951, Swick et al}^ and Lih and Baumann^^ reported that penicillin, 

 aureomycin, and streptomycin stimulated the growth of rats receiving 



35 T. H. Jukes, Federation Proc. 11, 447 (1952). 



39" D. V. Catron, R. W. Bennison, H. M. Maddock, G. C. Ashton, and P. G. Homeyer, 



J. Animal Set. 12, 51 (1953). 

 " L. D. Wright and A. D. Welch, Science 97, 426 (1943). 

 " F. S. Daft, Federation Proc. 10, 380 (1951). 

 « F. S. Daft and K. Schwarz, Federation Proc. 11, 201 (1952). 

 «« J. M. Hundley and R. B. Ing, Federation Proc. 12, 417 (1953). 

 «'• G. Everson, L. Northrop, N. Y. Chung, and R. Getty, Federation Proc. 12, 413 



(1953). 

 " R. W. Swick, H. Lih, and C. A. Baumann, Federation Proc. 10, 395 (1951). 

 ^^ H. Lih and C. A. Baumann, J. Nutrition 45, 143 (1951). 



