Description: Segment 1 The intertitles explain that the following experiments aid the search for synthetic drugs for the treatment of amoebiasis in humans. They also explain that young rats are suitable hosts for caecal infection with entamoeba histolytica. The cultivated amoebae are shown. A rat is shaved and cut open and its caecun injected with the amoebae. It is sewn back up and shown the next day. After one week it is cut open and the thickened and ulcerated caecum is shown. The infected caecum is compared with a normal caecum. An experiment is carried out in which rats are infected and then one group is left untreated and the other treated with emetine. The two sets of caeca are compared. The results from different strengths of emetine treatment are shown using graphs and charts. Time start: 00:00:00:00 Time end: 00:06:38:20 Length: 00:06:38:20