Dr. Murai Éva szerk.: Parasitologia Hungarica 13. (Budapest, 1980)

RESULTS I. Amylase activity in the maintenance medium of Ligula intestinalis larvae The maintenance medium of the freshly collected, washed larvae showed a considerable amylolytic activity after incubation of the stages for one hour. The amylolytic activity was still demonstrable after exchange of the medium, but at a significantly lower level (Table 1). Table 1 Amylolytic activity of the maintenance medium of L. intestinalis larvae as determined by the method of UJIHARA et al. (19 65) after 1 h incubation 1 h after exchange of the medium La.rval incubation medium Control medium Larval incubation medium Control medium X 0.4475 0. 29 0.3514 0. 29 S2 0.0030 0.0045 n 16 14 The mean values determined in the experimental series differed significantly, at 5% probability level. Table 2 shows the values of starch hydrolysis after different periods of incubation. Table 2 Effect of time on the hydrolysis of starch by L. intestinalis larvae. Hydrolysis determined by the dinitrosalycilic acid test Length of incubation (min.) 15' 60' 120' 180' X . 0.257 0. 365 0. 600 0, 6 50 S

2 0.003 0. 010 0. 086 0.009 n 4 4 4 4 II. Effect of live plerocercoid larvae on pancreatic amylase activity In the presence of plerocercoid larvae, starch hydrolysis increased over the sum of larval lytic activity and pancreatic amylase activity in the starch containing medium (Table 3) Table 3 Interaction of L. intestinalis larvae with pancreatic amylase KRT +10 mg/ml starch +parasites KRT +10 mg/ml starch + 10 jug/ml diastase KRT +10

i

pg/ml diastase +parasites X 0. 162 0. 13 0. 433 s

2 0.0006 0.0006 n 10 8