Factors Associated with the Incidence of Infantile Diarrhea in Mice. ∗

Abstract

Summary

1. Observations on 900s C3H mice born to 76 parents showed that 30% of the young contracted diarrhea severe enough to make it necessary that they be discarded. The 46 litters so affected comprised 50% of the offspring from 39 pairs of mice. 2. Observations on the 39 pairs of parents which had one or more litters afflicted with diarrhea showed that the litters born before and after clean boxes were supplied were not differentially susceptible to diarrhea. 3. Correlations between the incidence of diarrhea and age of parents, and seriation of litters and size of litters, showed that each of these had some influence on the numbers of litters showing symptoms of diarrhea. Litters from young parents having early parities and large litters showed highest incidences of the disease. The physiological condition of the parents common to these three factors seems to be an important consideration. 4. A higher incidence of the disease was observed in December than in either October or November. Part of the increased incidence in December was due to a greater number of large litters, early parities and younger parents. Superimposed upon physiological condition of the parents were other factors which were tentatively called seasonal influences.