GNATHOSTOMA-SPINIGERUM - GROWTH AND DEVELOPMENT OF 3RD-STAGE LARVAE IN-VITRO

Advanced third-stage larvae of Gnathostoma spinigerum were cultured in RPMI-1640, with various supplements at 37 C under 5% CO2 in air for 3 00 days. The most suitable medium supplement for worm development was 10% fetal calf serum, 1% dog serum, and 0.25% dog hemolysate. After ap proximately 180 days of cultivation, some larvae molted to the fourth stage as distinguished by 8 transverse rows of cephalic booklets and w ell differentiated sex organs. The maximum body length and width of th ese larvae were 18.6 mm and 1.1 mm, respectively. Six of 50 larvae (12 %) developed to the fourth stage, with a 32% survival rate at the end of cultivation. Although the highest survival rate (70%) of the worms was observed in the medium supplemented with 25 mM NaHCO3, only 4% dev eloped into fourth stage larvae. The addition of fetal calf serum, dog serum, and dog hemolysate was essential for growth and development.