Ascocotyle ascolonga (Witenberg, 1929) Travassos, 1930
ETYMOLOGY:Ascos (tube) + cotyle (disk) [referring to the shape of the anterior sucker being elongated within the body] and asco (tube) + longus (long).
SYNONYMS:Parascocotyle ascolonga Witenberg, 1929, Phagicolaascolonga (Witenberg, 1929) Price, 1932.
HISTORY: This parasite was originally described from specimens collected in small numbers from dogs and cats in Palestine (Witenberg, 1929).
GEOGRAPHIC DISTRIBUTION: Palestine. This fluke has been reported from Egypt (Azim, 1938) where it was also collected from 17 of 48 cats under the name Phagicolaascolonga (Witenberg, 1929) Price, 1932 (Kuntz and Chandler, 1956).
LOCATION IN HOST: Small intestine.
PARASITE IDENTIFICATION: This small fluke is 0.5 to 0.7 mm in length with a width of 0.1 to 0.3 mm. The body is covered with small, scale-like spines. The oral aperture is surrounded by a single row of 16 large spines. There is a funnel-like appendix on the oral sucker that has been the basis for the various other generic placements of this species. The testis lie side by side in the hind extremity of the body.
The eggs are 18 µm long by 9 µm in width, with thin shell, somewhat narrowed anteriorly and with distinctly visible opercula..
LIFE CYCLE: Dogs were experimentally infected by feeding them brackish-water fish (Tilapiasimonis and Tilapiagalilea) that contained metacercariae (Witenberg, 1929)
CLINICAL PRESENTATION AND PATHOGENESIS: Thought to be asymptomatic.
TREATMENT: Probably praziquantel, but not reported.
EPIZOOTIOLOGY: Cats probably are infected by eating raw fish..
HAZARD TO OTHER ANIMALS: None. Although other hosts are infected, the major means of infection is through the ingestion of the fish intermediate host which requires that the appropriate snail also be available. Thus, infection of these other hosts will typically only occur in the wild.
HAZARD TO HUMANS: None. Humans theoretically could become infected if they ingested an infected piscine host.
CONTROL/PREVENTION: Prevention of the ingestion of raw fish.
REFERENCES:
Azim MA. 1938. On the intestinal helminths of dogs in Egypt. J Egypt Med Assoc 21:??????
Kuntz RE, Chandler AC. 1956. Studies on Egyptian trematodes with special reference to the Heterophyids of mammals. I. Adult flukes, with descriptions of Phagicolalongicollis n. sp., Cynodiplostomumnamrui n.sp., and a Stephanoprora from cats. J Parasitol. 42:445-459.
Witenberg G. 1929. Studies on the trematode family Heterophyidae. Ann Trop Med Parasitol 23:131-239