Comparisons of different techniques for the isolation of Toxoplasma from naturally infected hosts were made with the following findings:
1.The use of multiple-animal passages did not result in the recovery of a significantly larger number of infections.
2.The use of cortisone in the dosages employed in the present work did not result in increased recovery rates.
3.Intraperitoneal inoculation was found to be much more efficient than intracerebral inoculation, possibly due to the much larger inocula which could be employed.
4.Intraperitoneal inoculation followed by sacrifice of inoculated mice at 1 and 2 weeks was about as efficient as intraperitoneal inoculation of mice followed by serological testing and examination at 6 to 8 weeks.
5.Infection per os was much less efficient than intraperitoneal inoculation, but was successful on a number of occasions.
6.Rabbits inoculated intraperitoneally became infected no more consistently than mice in spite of much larger inocula, thus indicating no advantage in the use of this animal.
7.An efficient technique for routine use was devised.