(F) Cestodes: Pseudophyllidea (module-based) Flashcards
- causes diphyllobothriasis or broad tapeworm or fish tapeworm infection
- also causes bothriocephalus anemia
- distributed worldwide but more at the northern temperate regions when pickled or insufficiently cooked fresh-water fishes are prominent part of the diet
Dibothriocephalus latus
Dibothriocephalus latus AKA
broad, or fish tapeworm
Dibothriocephalus latus was previously known as
Diphyllobothrium latum
Adult worms of Dibothriocephalus latus are frequently attached on the
- walls of ileum
- rarely in the jejunum
Dibothriocephalus latus
Morphology
- Sectorial groove or bothria
- Rectangular, with the width greater than the length
- Immature when laid, and with bubble-like germ balls.
- Globular-shaped, surrounded with cilia and contains a hexacanth embryo
A. Egg
B. Coracidium
C. Scolex
D. Segments
CDAB
Dibothriocephalus latus
Describe the shape of the scolex
Spatulate, or spoon-shaped
Dibothriocephalus latus
Segments: At the midline, ventral side, it has small, but prominent openings, which consist of? (2)
uterine and genital pore
Dibothriocephalus latus
58–76x40–51um(ave.66–44um)
Light golden-yellow in color
Broadly ovoid, operculate, with
moderately thick shell
Immature when laid, and with bubble-like
germ balls.
Egg
Dibothriocephalus latus
Result of the egg hatching in bodies of freshwater.
anong morphology
Coracidium
Life cycle: Dibothriocephalus latus
MOT
ingestion of plerocercoid or sparganum larva contained in the flesh of improperly cooked freshwater fishes
Life cycle: Dibothriocephalus latus
Ingestion of what fishes
like pike, salmon, and trout
Life cycle: Dibothriocephalus latus
Where does it mature
walls of ileum
Life cycle: Dibothriocephalus latus
After attaching to the walls, when does it lay eggs?
5-6 weeks
Life cycle: Dibothriocephalus latus
Stage of the egg passed with feces
Immature eggs
Life cycle: Dibothriocephalus latus
- On maturation of the egg, this escapes through the operculum and swims in the water
- The first intermediate host ingests this and later transforms into?
- The second intermediate hosts ingests the 1st inter. hosts then later transform into what larvae?
A. plerocercoid or sparganum larvae
B. procercoid
C. coracidium
CBA
Life cycle: Dibothriocephalus latus
first intermediate hosts
Tiny water crustaceans, like copepods