Platyhelmintheys

Question 1

3 important classes of platyhelminthyes

Answer 1

Monogenoidea - gill flukes (ectoparasites)
Trematoda - SC Digenea (endoparasites) blood/liver flukes
Cestoidea - endoparasites tapeworms

Question 2

Monogenoidea

Answer 2

• ectoparasites
• direct life cycle
• larvae = oncomiracidium
• prohaptor/opishaptor
• RAPID TRANSMISSION
• ovi+viviparous

Question 3

Monogenoidea larvae called what?

Answer 3

oncomiracidium

Question 4

monogenoidea’s attachment organs; what are they called, where are they located?

Answer 4

• prohaptor; anterior

- opishaptor; posterior

Question 5

monopisthocotylids vs polyopisthocotylids

Answer 5

one or many hooks (attachement structures)

• mono are tissue grazers
• poly are blood grazers (sanguiniformes) and have many structures so that they don’t damage the gills

Question 6

Gyrodactylosis. Tell me about it.

Answer 6

Viviparous reproduction (4 in 1)
juvenile fish suseptible
fin damage, skin discolored, BLUE GREY SLIME, lesions and secondary infections, renomelagy
- treatment = formalin, salt, reduce overcrowding, increase flow rates.
OIE REPORTABLE

Question 7

Class Trematoda, subclass digenea

Answer 7

endoparasites
INDIRECT life cycle
lack hooks
2 suckers.
fish intermediate OR definitive host
ZOONOSIS
water quality indicators

Question 8

what class of platyhelminthes lacks hooks?

Answer 8

subclass digenea, class trematoda

Question 9

Cryptocotyle lingua - class trematoda

Answer 9

black spot disease - spread by snails!
black cysts all over body and gills, fin erosion, discoloration, excessive mucus
LETHAL TO JUVES
marine

Question 10

Diplostomum spp - class trematoda

Answer 10

black spot disease, - FW

snails. remove snails. metaceraria invades vitreous humor of eye

Question 11

Prosorhynchus spp - class trematoda

Answer 11

mussel castrator.
mussels intermediate host.
harvesting and trsnsferring implications, more common in wild or bottom growing mussels, patchy distributions, inconsistent impact on health

Question 12

Class cestoidea - cestoda

Answer 12

-endoparasite
-lack gut/digestive system
-attachment organ = scolex
-proglottids: segments
-3 larvae
-indirect (heteroxenous) life cycle
Zoonosis

Question 13

tapeworm’s attachement organ?

Answer 13

scolex

Question 14

proglottid

Answer 14

segment of a tapeworm

Question 15

cestoidea - Eubothrium salvelini (salmon tapeworms)

Answer 15

adults infest intestine and pyloric caeca of salmon
fry very susceptible
smyptoms: poor swimming in fry, reduced growth
control: stock in fall.

Question 16

Diphyllobothriasis

Answer 16

larvae encysted in viscera and body wall, or enencysted in heart and muscle of fish and humans.
zoonosis
reduced weight, poor conditions, pale colour, visceral lesions, mortalities in young.
Control: stock in fall