A procedure is described for the determination of the egg producing capacity of female schistosomes from the time of maturation to the termination of infection. Using this procedure the comparative egg producing capacities of female S. mansoni and S. japonicum were studied in the hamster and information obtained on the relative distribution of eggs in the feces and in the various tissues and organs.
Each female of S. mansoni produced an average of 300 eggs per day within the period under study. Only 22 per cent of all eggs produced were passed in the feces; 18 per cent remained in the wall of the large intestine; 32 per cent in the small intestine; 26 per cent in the liver; and 2 per cent in the mesenteries and its associated lymph nodes and pancreas. The percentage of eggs found in the spleen and lungs was small and numerically insignificant.
Each female S. japonicum produced an average of 3500 eggs per day. Only 16 per cent of all eggs produced were passed in the feces; 50 per cent were found in the wall of the large intestine; 10 per cent in the small intestine; 23 per cent in the liver and 17 per cent in the mesenteries, associated lymph glands and pancreas. As in the S. mansoni infections, the percentage of eggs found in the spleen and lungs was small and insignificant.
Present address: Department of Microbiology, The University of Texas Southwestern Medical School, Dallas, Texas.
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