Table of Contents
Are trematodes and flukes the same?
Trematoda is a class within the phylum Platyhelminthes. It includes two groups of parasitic flatworms, known as flukes. They are internal parasites of molluscs and vertebrates. Most trematodes have a complex life cycle with at least two hosts.
What are metacercariae cysts?
Metacercariae of the echinostome family is encysted in snails, fishs, and amphibians. The cyst is oval or round; the metacercariae can be folded or not, and they possess collar spines and corpuscles in their excretory tubes, which is characteristic of echinosomes’ cercariae and metacercariae (Fig. 4.6).
What is metacercariae larva?
Definition of metacercaria : a tailless encysted late larva of a digenetic trematode that is usually the form which is infective for the definitive host.
What is the life cycle of trematode?
There are three distinct larval stages involved in all digenetic trematode life cycles: the miracidium, sporocyst, and cercaria. Some taxa also produce rediae and/or encysted metacercariae. All of these life stages except for the miracidium can be found in first intermediate hosts.
Which of the following parasite metacercariae are found in fish?
Heterophyid metacercariae are usually found encysted in many families of fish, such as: Cobitidae, Cottidae, Cyprinidae, Gobiidae, Mugilidae, Ophicephalidae, Percidae, Plecoglossidae, or Siluridae.
What is a sporocyst?
1 : a case or cyst secreted by some sporozoans preliminary to sporogony also : a sporozoan encysted in such a case. 2 : a saccular body that is the first asexual reproductive form of a digenetic trematode, develops from a miracidium, and buds off cells from its inner surface which develop into rediae.
How do you test for liver flukes in humans?
The infection typically is diagnosed by examining stool (fecal) specimens under a microscope. The diagnosis is confirmed if Fasciola eggs are seen. More than one specimen may need to be examined to find the parasite. Certain types of blood tests also may be helpful for diagnosing Fasciola infection.
What are fish borne trematodes?
Background. Fish-borne zoonotic trematodes (FZT) are transmitted by fish and fish products, and pose a major public health problem [1-3]. People become infected with FZT after ingesting raw or undercooked freshwater fish containing infective metacercariae [3-5].
Is Metacercariae singular or plural?
noun, plural met·a·cer·car·i·ae [met-uh-ser-kair-ee-ee]. Zoology.
How do you say Miracidium?
noun, plural mi·ra·cid·i·a [mahy-ruh-sid-ee-uh].
What is the difference between metacercariae and trematodes?
The metacercariae are an adapted cystic form dormant in the secondary intermediate host. The adult is the fully developed form which infects the definitive host. Human infections are most common in Asia, Africa and Latin America. However, trematodes can be found anywhere where untreated human waste is used as fertilizer.
What is a metacercariae?
The metacercariae are an adapted cystic form dormant in the secondary intermediate host. The adult is the fully developed form which infects the definitive host. Human infections are most common in Asia, Africa and Latin America.
What is the lifespan of metacercariae in humans?
After ingestion, the metacercariae excyst in the duodenum and attach to the intestinal wall. There they develop into adult flukes (20 to 75 mm by 8 to 20 mm) in approximately 3 months, attached to the intestinal wall of the mammalian hosts (humans and pigs) . The adults have a life span of about one year.
How many species of trematode metacercaria are there in Korea?
More than 10 species of digenetic trematode metacercariae in 3 families have been found in brackish water fishes in the Republic of Korea (Table 2).