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Table 2 Characteristics of Fasciola hepatica infection in Lymnaea fuscus (F5 generation), Radix balthica (F5 generation) and Galba truncatula subjected to individual bimiracidial exposures and raised at 20°C (second experiment)

From: Adaptation of Lymnaea fuscus and Radix balthica to Fasciola hepatica through the experimental infection of several successive snail generations

Population Lymnaea fuscus Radix balthica Galba truncatula Significant differences*
Number of snails:     
- at exposure 100 100 100  
- at day 30 p.e. (%) 54 (54.0) 65 (65.0) 74 (74.0) χ2 = 8.74, p < 0.05
Number of snails:     
- CS 7 13 43  
- NCS 12 14 11  
Prevalence of infection (%) 35.1 41.5 72.9 χ2 = 21.99, p < 0.001
Shell growth (mm):     
- CS 7.7 ± 1.5 6.0 ± 1.1 3.7 ± 0.9 F = 14.32, p < 0.001
- NCS 7.3 ± 1.1 5.7 ± 0.8 3.5 ± 1.1 F = 16.63, p < 0.001
Prepatent period in days 55.7 ± 6.5 57.1 ± 8.3 43.3 ± 5.2 F = 4.42, p < 0.05
Patent period in days 11.2 ± 4.7 16.1 ± 5.2 28.8 ± 7.3 F = 10.21, p < 0.001
Number of shed cercariae 80.3 ± 35.8 66.8 ± 21.2 157.1 ± 55.2 F = 7.10, p < 0.01
Cadavers of NCS snails:     
- Free rediae 15.7 ± 5.2 18.3 ± 4.5 31.5 ± 5.3 F = 11.71, p < 0.001
- Free cercariae 137.6 ± 37.0 154.2 ± 52.9 236.5 ± 67.1 F = 4.68, p < 0.05
Percentage of shed cercariae** 58.3 43.3 66.4  
  1. *Mean values are given with their standard deviations for seven parameters. Each statistical comparison was performed using values recorded for the three lymnaeid species. CS, cercariae-shedding snails; F, value of ANOVA; NCS, non cercarial shedding snails containing cercariae; NS, non significant difference; p, probability; p.e., post-exposure; χ2, value of the χ2 test.
  2. **Number of cercariae shed by CS snails / overall cercarial production in NCS snails.