/l/ Deficiency signs, when not irreversible, may be alleviated, and the animal restored to health by the administration 

 of therapeutic doses of the vitamin. /lO/ Sock causes of deficiency signs, other than dietary deficiency of the vitamin, 

 are: any factor iiiq>airlng digestion or absorption of fat, as inflaimatlon of intestinal mucosa, sprue, or chronic diar- 

 rhea; excessive ingestioa of mineral oil; relatively greater requirement during pregnancy and lactation. /I6/ A number 

 of synthetic products having a qulnold nucleus have vitamin K activity, e.g., menadione (2-methyl-l,U-naphthDquinone) . 

 The synthetics tend to be more toxic (In excessive amounts) than the naturally occurlng vitamin. /l7/ The following 

 therapeutic uses of the vitamin have been noted: stimulation of prothrombin production; reduction of prothrombin clot- 

 ting time. Ineffective in treatment of hemorrhagic diseases not due to prothrombin deficiency, e.g., hemophilia, throm- 

 bocytopenia. In hypoprothromblnemia of the newborn, prevention and treatment (man). Counteracts effects of dlcumarol 

 (man, others). /I8/ Vitamin K deficiency does not precipitate bleeding; the abnormality Is failure of clotting after 

 bleeding has begun. /l9/ The prothrombin stimulating properties of vitamin K act throu^ the site of prothrombin pro- 

 duction (liver), and the vitamin, even in large amounts, is ineffective If the prothrombin producing tissues are damaged 

 or liq>alred. /ZO/ The syndroce of deficiency symptoms is referred to as "Pellagra" in man and "blacktongue" in dogs, 

 cats, and other animals. /Sl/ Ratio, therapeutic dose: toxic dose > 1:1000. 



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