Abstract
Metacercarial cysts ofParorchis acanthus preserved in sea water have a much greater longevity and a greater capacity to excyst in vitro and in vivo than those preserved under dry conditions. Increasing temperatures reduce the viability and excystment rate of the metacercariae. After encystment, metacercariae must reach a minimum age before they can excyst in vivo or in vitro and be infective. Maximum percentage excystment varies with the temperature of the environment and decreases with increasing temperatures. Not all metacercariae can excyst even when they are alive and are sufficiently activated. The chief sites for the excystment ofP. acanthus metacercariae in vivo are the duodenum and intestine. The in vitro excystment results corroborate with those obtained in vivo.
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Asanji, M.F., Williams, M.O. Effect of age and environmental factors on the viability and excystment of metacercarial cysts ofParorchis acanthus in vivo and in vitro. Z. Parasitenkd. 71, 595–601 (1985). https://doi.org/10.1007/BF00925592
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DOI: https://doi.org/10.1007/BF00925592