1. A diet of whole wheat and whole dried milk has been shown to promote a higher survival rate, among W-Swiss mice subjected to S. enteritidis infection, than that promoted by a "synthetic" diet.
2. The demonstration of this ability of diet to condition natural resistance has been found to depend upon the genetic constitution of the mice employed. The demonstration has been possible in W-Swiss mice, a strain only moderately inbred and retaining a degree of genetic variability. The demonstration has not been possible in three highly inbred strains of mice selected so that they differed predictably from one another in natural resistance.
3. The nutritional factors involved are present in whole wheat and are absent or negligible in dried whole milk. Their nature has not yet been determined.