PYRIDOXINE 



Pigs. The omission of pyridoxine and pantothenic acid from the 

 diet of pigs led to the development of an abnormal gait and degenera- 

 tive changes in the peripheral nerves, posterior root ganglia and the 

 posterior roots and posterior funiculi of the spinal cord.^^ The 

 omission of pyridoxine alone caused epileptiform convulsions of both 

 grand mal and petit mal type, together with a severe microcytic 

 anaemia. The administration of pyridoxine resulted in a sharp 

 reticulocyte response and rapid regeneration of the blood, iron being 

 mobilised from the tissues. ^^ The anaemia was due to failure to 

 synthesise protoporphyrin. ^^ 



The gait of vitamin Bg-deficient pigs differed from that of 

 pantothenic acid- deficient pigs, the former exhibiting swaying and 

 twisting of the legs and the latter a " goose-step " type of gait.^^ 

 Degeneration of the peripheral process of the sensory neurone was the 

 initial and most prominent feature in vitamin Bg deficiency, whereas 

 chromatolysis was the first evidence of damage in the afferent neurone 

 in pantothenic acid deficiency. The rate of haemolysis in phenyl- 

 hydrazine anaemia in pigs was not increased in vitamin Bg deficiency. ^^ 



Monkeys. Symptoms of pyridoxine deficiency in young monkeys 

 included lack of growth, ataxia, hypochromic microcytic anaemia, 

 mild leucopenia, polychromatophilia and the appearance of nucleated 

 red blood cells. ^^ 



Birds and Fish. The symptoms of vitamin Bg deficiency in chicks 

 included decreased clotting time, hyperthrombinaemia, small spleens 

 and anaemia,^^ in addition to convulsive symptoms,^' '^ already re- 

 ferred to (page 318). Turkeys exhibited convulsions, but not anaemia,^ 

 and young ducklings severe anaemia, but not convulsions.^^ Older 

 ducklings, on the other hand, developed a chronic deficiency char- 

 acterised by failure to grow, paralysis, convulsions, severe macrocytic 

 anaemia and poor feather development.^^ 



The anaemia of chicks was cured by a combination of a- or ^-pyracin 

 (page 344) and folic acid. When only folic acid was added, the 

 anaemia became normocytic and hypochromic, whilst with j3-pyracin 

 only, it became macrocytic and normochromic. ^^ 



In the absence of vitamin Bg, young rainbow trout suffered from 

 nervous disorders, and developed pale spots on the liver. ^^ The 

 symptoms were prevented by the addition to the diet of o-i to i-o 

 mg. of pyridoxine per 100 g. 



Vitamin Be and Immunity 



Axelrod et al.^^ reported severe impairment of antibody response 

 in pyridoxine-deficient rats, and this was confirmed by L. R. C. 

 Agnew and R. Cook,^^** whilst H. C. Stoerk and H. N. Eisen ^^ observed 



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