Fig. 3

Effects of spirulina on reducing cercariae counts per week of infection. A Each column shows the mean number of cercaria released from groups of infected snails collected at 4, 6 and 8 weeks from feed-treated infected snails. Student's t test was used to determine the significance of differences in means between two groups. B Each column shows the mean number of cercaria released from groups of infected snails collected at 5, 7 and 9 weeks from feed-treated infected snails. Student's t test was used to determine the significance of differences in means between two groups. C Ratio of the mean number of cercariae released by spirulina administration in the base feed. D Columns showing the total number of cercariae recovered from each weekly infected group