Mesostephanus milvi Yamaguti, 1939
(Fig. 2.2)
ETYMOLOGY:Meso (middle) + stephanus (crown) [referring to the organization of the vitellaria in the middle of the body] and milvi for the generic name of the kite, Milvusmigrans, host from which it was originally described.
SYNONYMS:Prohemistomum milvi (Yamaguti, 1939) Dubois, 1951; Mesostephanusindicus Vidyarthi, 1948; Gelanocotylemilvi (Yamaguti, 1939) Sudarikov, 1961.
HISTORY: This species was first described from worms collected from a kite, Milvusmigranslineatus, in Japan. Specimens were recovered from two cats from the Daqahliya province of Egypt (Dubois and Pearson, 1963) and again in 4 cats of the Assiut province by Fahmy et al. (1984).
GEOGRAPHIC DISTRIBUTION: Japan, India, Africa - Although it has only been reported from cats in Egypt.
LOCATION IN HOST: Small intestine.
PARASITE IDENTIFICATION: These are very small trematodes that are 1.5 to 2 mm long and about twice as long as they are wide. The small oral sucker, about 100 µm in diameter, is similar in size to the ventral sucker. The ventral sucker is located at midbody, and just behind the ventral sucker is the circular tribocytic organ that is about one-third of the body's width. The sexual organs are located posterior to the ventral sucker, and there is a small elongation of the posterior end of the body.
The oval eggs are large, yellowish brown, operculate, 100 µm long by 60 to 70 µm wide, and not embryonated when they leave the fluke (The eggs are embryonated according to Fahmy et al., 1984.)
LIFE CYCLE: The life cycle of Mesostephanusmilvi has not been elucidated. The life cycle of another Cyathocotylids, Prohemistomum vivax has been investigated (See below).
CLINICAL PRESENTATION AND PATHOGENESIS: Asymptomatic.
TREATMENT: Probably praziquantel, but not reported.
EPIZOOTIOLOGY: Cats become infected by eating fish containing the metacercariae. The flukes are capable of developing to the adult stage in a few days.
HAZARD TO OTHER ANIMALS: None.
HAZARD TO HUMANS: None.
CONTROL/PREVENTION: Prevent cats from eating raw fish.
REFERENCES:
Dubois G, Pearson JC. 1963. Les Strigeida (Trematoda) d’Egypte (Collection William H. Walls). Ann Parasitol 38:77-91.
Fahmy MA, Arafa MS, Khalifa R, Abdel-Rahman AM, Mounib ME. 1984. Studies on helminth parasites in some small mammals in Assiut Governorate. 1. Trematode Parasites. Assiut Vet Med J. 11:43-52.
Figure 2-2.Mesostephanusmilvi recovered from a cat in Egypt.