الملخص
The present study investigated the effect of the Nd-TAG Laser radiation 1000 mw on the viability of the protoscolices of Echinococcus granulosus in vitro, for different durations 40,60,120 and 240 minutes, and on the immune response in BALB/c mice against infection with secondary hydatid disease by injecting the mice with protoscoleces of Echinococus granulosus treated with laser radiation, 70%,57%,50% and 40% viability, compared with the control group of (mice injected with untreated protoscolices with the laser radiation) through three months, depending on many criteria including numbers, weights and diameters of the hydatid cysts and the percentage of reduction of their numbers. The results revealed an obvious decrease in the mean of number, weights and diameters of secondary hydatid cysts, during three months, in treated mice the minimum number was, 0.00 in 240 minutes, one month post infection,at (P<0.01) in comparison with the positive control group, 2.6, 3.404mg and 2.48mm, respectively.