[Method for obtaining Paramphistomum daubneyi, Dinnik, 1962 metacercariae].
Miracidium ova were obtained from the feces of a ram that was experimentally infected with Paramphistomum daubneyi. The fecal masses were extended in the respective amount of water and were passed through a standard sieve, 0.150 and 0.080. The ova were collected in the second sieve, and were rinsed several times after the method of successive sedimentation. They were cultured in a thermostat at 26 degrees C in the course of 12 days. Test molluscs of the G. truncatula species (a laboratory strain) were raised after the method of Kendall, and were infected wtih 2 to 5 miracidia each. The cercariae matured for 32 to 50 days and remained in the infected molluscs. The shedding of mature cercariae was enhanced by placing the molluscs on narrow leaves of Plantago lanceolata under a thin layer of dechlorinated water at 15-20 degrees C. At temperature values of 10-15 degrees C and 20-25 degrees C the elimination of cercariae was retarded, while at higher ones (above 25 degrees C) it completely ceased. The eliminated cercariae were slightly motile. They formed cysts on the leaf surface in 10-30 min. The first challenge was carried out 50-60 days after infecting the molluscs, and the following ones--at 7-10-day intervals. The metacercariae were allowed to stay at room temperature for 48 hours after which they were either used in tests or kept in a refrigerator at 1-4 degrees C. Prior to using them in an experiment they were taken from the leaf surface through washing the leaves and were counted. As many as 94 up to 1628 metacercariae were obtained from a single snail.
D000818:Animals; D005243:Feces / Q000469:parasitology; D008297:Male; D008722:Methods; D010250:Paramphistomatidae / Q000302:isolation & purification*; D012756:Sheep / Q000469:parasitology; D012908:Snails / Q000469:parasitology
Metod za poluchavane na metatserkarii ot Paramphistomum daubneyi, Dinnik, 1962.