A liver extract No. 343, N.N.R. known to be fully potent in pernicious anemia shows but 10 to 20 per cent of the potency of whole liver feeding in severe continuous secondary anemia due to bleeding in dogs. There are wide individual variations which are not noted with whole liver feeding.
Supplementing this liver extract with whole bile does not modify the reaction.
Supplementing this liver extract with liver ash or apricot ash shows the sum of the two expected feeding reactions.
When we supplement this liver extract with small amounts of whole liver (50 to 100 gm.) we may observe hemoglobin and red cell production in excess of the sum of the expected separate reactions. Whether the liver extract increases the potency of the whole liver feeding or vice versa, it suggests similar possibilities in various human secondary anemias.
Liver and kidney fractions of varied types deserve much study to ascertain their effect upon widely divergent types of human anemias.