Studies On Intestinal Trematodes In Korea: IX. Recovery Rate And Development Of Fibricola Seoulensis In Experimental Animals.

An experimental study was carried out to observe the susceptibility of several kinds of laboratory animals to Fibricola seoulensis infection, a diplostomatid fluke of mammals. The metacercariae were obtained from the viscera of the snakes, Natrix tigrina lateralis and 50-2,000 in number each was artificially fed to a total of 127 animals; albino rats, mice, dogs, cats, rabbits and chickens. After 3 days to 8 weeks the animals were sacrificed and the recovery rate of worms as well as their maturity was observed. The results are as follows: The overall wom recovery rates throughout the experimental period was highest in albino rats(40.0 %) followed by mice(33.9%), cats(20.9 %), dogs(11.4 %), rabbits(0.05 %) and chickens(0 %). However, the recovery rates in the same host decreased as infection progressed longer and variable by the amount of metacercariae given. From albino rats and mice, the highest recovery rates were obtained in 1,000 and 200 metacercariae infection groups repectively, and it is considerd that such amount should be the optimum dose for experimental infection of these animals. The main location of F. seoulensis in experimental animals was small intestine especially the duodenum. The maturity index (No. mature worms/No. examined) was 100% in albino rats and mice, while only 22.7% or 0% in dogs or cats respectively. From the results, it is concluded that albino rats and mice are the most susceptible hosts for F. seoulensis infection among six kinds of laboratory animals examined.