Strongyloides ratti (homogonic): the time-course of early migration in the generalized host deduced from experiments in lactating rats

Abstract

Unsuckled mother rats given a 1 h suckling stimulus 3 h after subcutaneous injection of an exact dose of homogonic Strongyloides ratti allow fewer worms to develop in their intestines by day 8 than nulliparous rats (Wilson & Simpson, 1981). This effect is studied in more detail in terms of the length of time between weaning and stimulus (W → S) and injection and stimulus (I → S). It was observable with a W → S of 30 h but this and a period of 5 h were less effective than 24 h. With W → S constant at 24 h, significantly more worms developed in mothers when I → S was 24 h compared to 3 h and 10 h (P < 0·005). The data, combined with those from nulliparous controls, are presented as a measure of the change with time of numbers of larvae in that compartment of the system which gives access to the stimulated mammary gland. It is argued that the particular compartment is the local lymph node draining the injection site and that the kinetics deduced are applicable to migration in the rat in general