Abstract
Infection with Trichinella spiralis causes a moderate eosino-philia in the blood of Mesocricetus auratus. The eosinophilia reaches a peak 16-19 days post-infection and returns to normal about a week later. No correlation between eosinophilia and weight loss of infected hamsters was noted. There is a lymphopenia during the second and fifth weeks post-infection. The dilution method for the determination of absolute eosinophil numbers in the peripheral blood was found not to be as sensitive to changes as the differential count, at least when the technique was applied to blood from infected animals.