EFFECT OF DEFICIENCY IN ANIMALS 



increased the lactate, whereas in normal animals both were decreased. ®® 

 Injection of glucose had the reverse effect, increasing the pyruvate 

 and lactate of normal animals and the lactate-pyruvate ratio of 

 vitamin Bi-deficient dogs, following an initial decrease.®^ Anaemia 

 is not a symptom of vitamin Bj deficiency in dogs.^^ 



Cats exhibit three stages in the development of vitamin B^ de- 

 ficiency : ^^ (a) an induction stage, with development of anorexia ; 

 {b) a cortical stage with neurological disturbances, particularly of 

 postural, mechanical and tonic convulsive seizures ; and (c) a terminal 

 stage in which the animal is prostrate ; this is followed by death in 

 one to two days. The first and second stages, but not the third, are 

 reversed by injection of aneurine. After one to two weeks on a vitamin 

 Bi-deficient diet, cats showed a 50 % increase in the length of time 

 they were able to maintain respiration in 3-25 % oxygen.^* 



The symptoms exhibited by monkeys (Macaca mulatto) on a diet 

 deficient in aneurine were : ^^ loss in weight, decreased food con- 

 sumption, general muscle weakness, loss of reflexes, convulsions, 

 inco-ordination, increased cachexia, signs of cardiac insufficiency, 

 prostration and, finally, death. No vomiting or opisthotonus was 

 observed. About 15 /itg. of aneurine per kg. of bodyweight per day 

 were required to prevent the onset of deficiency and 25 to 50 /xg. for 

 adequate growth. The pyruvic acid content of the blood in normal 

 monkeys was found to be higher than in normal human or pig blood ; 

 it increased in aneurine deficiency. 



Vitamin B^ deficiency in the calf results in weakness, inco-ordination 

 of the legs, convulsions, head retraction and sometimes scouring, 

 anorexia and dehydration ; the blood and urinary pyruvate are 

 increased above the normal levels. ^^'^ 



Aneurine and the Alimentary Tract 



It was at one time supposed that absence of vitamin B^ produced 

 adverse changes in the alimentary tract, but this is now known not to 

 be the case. For example, two groups of workers ^^ observed gastric 

 ulcers in a large proportion of rats on a vitamin Bi-deficient diet, but 

 these are now believed to be due to a secondary and not a direct effect 

 of the lack of vitamin B^. B. P. Babkin ^' appears to have obtained 

 evidence that absence of some member of the vitamin B complex 

 reduces the response of the gastric glands to the normal stimuli pro- 

 vided by the right kind of food. Feeding yeast restored the response 

 to normal but unfortunately no attempt was made to establish the 

 nature of the responsible factor. It is possible that Babkin 's observa- 

 tions provide an explanation of the association between vitamin B^ 

 and anorexia. 



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