Wplyw doboru tasiemcow macierzystych linii wsobnej Hymenolepis diminuta WMS IL1 na zmiennosc cech u tasiemcow potomnych

A continuation of a single-individual culture of Hymenolepis diminuta WMS ill from generations 37 to 66 revealed a very high infective ability of cysticercoids which is reflected in the percentage of tapeworms detected in relation to the number of cysticercoids given to rats (94.4%). The tapeworms investigated revealed a significant increase in the abundance of type 0p3a proglottids (those wilh no testes on the poral side and 3 on the aporal) in tapeworms of successive generation groups. Each group of tapeworms analysed statistically belonged to three successive generations and numbered 31-34 individuals. The mean abundances of 0p3a type proglottids in tapeworms of the first groups studied in experiment, including generations 37-39 and 40-42 were 9.2% and 9.5%, respectively. The last studied groups, including generations 61-63 and 64-66 had higher mean numbers of type 0p3a proglottids, at 11.1 % and 11.5%, respectively. The quantitative figures of 1p3a type proglottids amounted to 1.6% and 1.3% in first generation groups and in the last two groups 0.8% and 1.0%, respectively. The probable cause of this significant (P < 0.01) relative increase in the numbers of 0p3a type proglottids and decrease (P < 0.01) in the numbers of 1p3a type proglottids was the deliberate selection of maternal tapeworms characterized by numbers of 0p3a type proglottids greater and 1p3a type proglottids smaller than the a verage for their generation.