SUSCEPTIBILITY AND REACTION OF SHEEP TO TRICHINELLA-PSEUDOSPIRALIS INFECTION

The susceptibility and reaction of sheep to Trichinella pseudospiralis infection were followed for 247 days. Infection with 80 000 larvae re sulted in the production of anti-Trichinella antibodies on Day 21 p.i. with titre of 1 : 200, which persisted until Day 42. On Day 32 p.i. l arval Trichinella pseudospiralis were present in all nine muscles exam ined. They were increasing in number from Day 59 p.i., reaching a maxi mum on Day 115 p.i. in the masseter muscle, which is a predilection si te for the localization of T. pseudospiralis larvae. None of the muscl es showed the presence of live larvae on Day 247 p.i. Necrotized larva e were observed in sheep muscles from Day 32 p.i. Neither live nor nec rotized larvae caused any cellular activation during the experiment. N ecrosis of larvae and of surrounding muscle fascicles did not result i n the formation of secondary connective tissues but in the regeneratio n of muscle tissues.