Biological studies on Trichinella spiralis in experimentally infect ed rats revealed some important aspects on control and preven tion of trichinosis among man and animals. The larvae of T.spiralis have been noticed in the feacal matter from the second to the third day post infection. These were considered as important phenomena for transmission of trichinosis as well as one of the important epidemiological factor in their prevention. Signs of fever, irritability and convulsions of the infected rats were noticed although the brain tissue was free of larvae.
Adult worms were concentrated in the anterior half of the small intestine, the stomach was noticed to harbour the adult worm in two cases with very few number of worms (3 & 5 worms in each case respectively). The most heavily infected muscle with larvae was the diaphragm followed by tongue, masseter, intercostal, hind!imb, forelimb and finally the muscle of the tail.
Mild inflammation accompanied by massive infilteration of polymorphnuclear leucocytes was observed at the first few days. The inflammatory reaction end by fibrosis. The pathologi cal effects were noticed to be increased with the highest doses of larvae and decreased with the lowest doses.