Vitamin B 1 Deficiency and Attempts to Produce Poliomyelitis in White Rats.

Abstract

The experiments reported in this paper are the first of a series, the purpose of which is to determine whether Flexner's M.V. strain, which has been acclimated to Eastern cotton rats, could in turn be acclimated to white rats by some vitamin deficiency or imbalance.

This first series was with B₁-deficient animals. White rats were fed a vitamin B₁ test diet made up as follows: sucrose—62.1%; vitamin free casein—18.6%; peanut oil—7.8%; salt mixture—4.2%; cod liver oil—2.3%; and alkaline autoclaved brewer's yeast—5.0%. When the animals first started this diet, they were from 22 to 26 days old and weighed between 40 and 50 g.

We had ascertained that white rats from our colony had to be kept on this diet 30 days before they developed full-blown B₁ deficiency. If the diet were continued the animals would start to die beginning about the thirty-eighth day. This left 8 days in which to demonstrate additive effects of poliomyelitis virus. Signs and symptoms should appear after the fifth or at least before the eighth day following injection of virus, which occurred on the thirtieth day of the diet. There was sufficient time since reactions begin to appear in Eastern cotton rats about the fourth to fifth day after injections with Flexner's M.V. cotton rat-adapted strain.

A second difficulty arose. Vitamin B₁-deficient rats have a polyneuritis. It might be difficult to distinguish this condition from that produced by poliomyelitis virus, especially since the early clinical appearance of white rats which are vitamin Bi-deficient and cotton rats infected with poliomyelitis are alike, i.e., they are furred, have tremors, apraxia and weakness.