Marcer Lecture 1 Flashcards
What are the different relationships among organisms?
What are the different forms of parasitism?
- Obligate parasite (permanent, temporary and periodic): completely dependent on the host in order to complete their life cycle.
- Facultative
- Accidental
Endoparasitism vs Ecoparasitism
Ecto: e.g. copepods and leeches
Polyparasitism vs pseudoparasitism
- Poly: cohabitingparasitic species in the same host
- Pseudo: other parasite species accidentally ingested without taking root in the host
What are the different life cycles in parasites?
- Monoxenous parasite (Direct life cycle): parasite with direct evolution on a
single host with or without a free
phase in the external environment. - Eteroxenous parasite (Indirect life cycle): one or more intermediate hosts
What is the intermediate host?
Organism NECESSARY for the
completion of the parasite life
cycle, of which it hosts one or
more LARVAL STAGES
What is the definitive host?
organism ESSENTIAL to complete
the life cycle of the parasite, which
hosts the ADULT STAGE.
Host in which parasite reaches
sexual maturity
What is a paratenic host?
Organism in which the parasite can
survive even for a long time
without undergoing a significant
development. It is not necessary
for the life cycle of the parasite
What is an accidental host?
Organisms penetrate a different
host species than usual, but which
are able to survive at least for
some time on it.
Humans are an accidental host of the parasite
Anisakis.
Determinants of (parasitic) disease
According to the conservation code of the carcass (from code 1 to code 3 for parasitological examination), a
parasitological examination should be done for many reasons….
▪ Parasite diversity in specific host population/geographical area
▪ pathogenic effects of the parasites
▪ health of the marine environment and food web
▪ biological tags (to trace migration route)
What parts of body are most important for parasitological examination?
- Skin
- Blubber and body cavity
- kidney
- GIT (many species of parasites)
- lungs
What are epbiobionts and 2 different types?
- Parasites of the skin
- Ectoparasites: : strictly depend on the host-usually high host specificity
- Commensals: obligate (ex. Coronulid barnacles), very broad host spectrum
- Xenobalanus globicipitis (Crustacea Cirripedia)
Barnacles are obligate epibionts of
- cetaceans
- sea turtles
- Sirenids
Flipper, flukes, ect
Conchoderma auritum e C. virgatum
(Cirripedia, Lepadidae)
Epibionts of cetaceans, sea turtles and fish
- Cyamidae (Crustacea, Amphipoda)
- Whale lice
- High host-specificy (only parasitizes humpback whales)
- Entire life cycle on the host (need direct contact for transmission)
- Short life cycle makes the louse a great candidate as biological tags to study
whale migration route
- Pennella spp (crustacea, Pennellidae)
- Copepod
- In odontocetes and whales
What is useful about whale lice?
Can be used as biological tags to study
humpback whale migration route (genetical similarity between lice of Atlantic and pacific populations = maybe interaction in feeding area).
- Pennella spp (crustacea, Pennellidae)
- Copepod
- In odontocetes and whales
How can crustacean ecoparasites be used as health indicators in cetaceans?
If an animal has already other
disease it can swim slower, which allows the attachment of larval stages of parasites
What does Pennella spp feed on?
Blood. They reach an area called ‘Fascia’ under skin and blubber