Introduction to Virology and Parasitology Flashcards
What is mutualism in symbiosis?
Mutualism is a type of symbiosis where both organisms involved benefit.
What is commensalism in symbiosis?
Commensalism is a type of symbiosis where one organism benefits, but the other is not harmed or affected.
What is parasitism in symbiosis?
Parasitism is a type of symbiosis where one organism benefits at the expense of the other.
What is a definitive host (DH)?
A definitive host supports the adult or sexually reproductive form of a parasite.
What is an intermediate host (IH)?
An intermediate host supports the immature or non-reproductive forms of a parasite.
What is a paratenic host (PH)?
A paratenic host acts as a substitute intermediate host, aiding in transmission without development of the parasite.
What does the formula C = M + E + T stand for in integrated parasite control?
Control = Management + Epidemiology + Treatment.
Why is management important in parasite control?
Clean, healthy animals in a controlled environment are less likely to encounter or be infested by parasites.
Why is epidemiology important in parasite control?
Understanding the specific transmission, lifecycle, and environmental preferences of each parasite aids in control.
Why should treatment not be solely relied upon for parasite control?
Parasites develop resistance quickly, making it crucial to use a combination of control methods.
Name the major parasite assemblages.
Protists (protozoa), Nematodes (roundworms), Trematodes (flukes), Cestodes (tapeworms), Arthropods (crustaceans, insects, arachnids).
What are ectoparasites?
Ectoparasites are parasites that live on the external surface of the host (e.g., ticks).
What are endoparasites?
Endoparasites are internal parasites that live inside organ systems, digestive tracts, or blood (e.g., nematodes).
What are permanent parasites?
Permanent parasites remain on the host for their entire lifecycle (e.g., lice).
What are temporary parasites?
Temporary parasites only associate with the host briefly during their lifecycle (e.g., mosquitoes).
What are obligate parasites?
Obligate parasites are entirely dependent on the host for survival (e.g., fleas).
What are facultative parasites?
Facultative parasites can live without a host but can become parasitic under certain conditions (e.g., blowflies).
What is Giardia lamblia?
Giardia lamblia is a flagellate protist that causes giardiasis, a diarrheal illness.
How is Giardia transmitted?
Giardia is transmitted through contaminated surfaces, soil, food, or water, often from feces of infected humans or animals.
Why are nematodes significant endoparasites?
Nematodes are significant because they cause major economic losses in livestock industries, such as sheep and wool.
Describe the general lifecycle of nematodes.
Nematodes have a direct lifecycle: eggs hatch in the environment, larvae develop to infective stage (L3), ingested by host, mature to adults inside the host.
What are the disease-causing stages of cestodes?
Both adult intestinal tapeworms and larval cysts can cause disease depending on the species involved.
Which fluke is the most important and causes serious disease?
Liver fluke (Fasciola hepatica) is the most important fluke, causing serious disease in livestock.
What are the key strategies for liver fluke control?
Strategies include strategic anthelmintic treatment, reducing intermediate host snails, and managing fluke-prone areas.
What is the lifecycle of ticks?
Ticks have a lifecycle involving egg, larva (6 legs), nymph (8 legs), and adult (8 legs).
What are some pathogenesis effects of ticks?
Ticks can cause anemia, irritation, allergic reactions, transmission of diseases, and toxin production.
What is the life cycle of Ixodes holocyclus (paralysis tick)?
Ixodes holocyclus has a 3-host lifecycle, natural hosts are bandicoots, lifecycle may take up to 2 years, female lays 2000-3000 eggs.
What is the main period of infection for Ixodes holocyclus?
The main period of infection is spring, with a secondary peak in autumn.
What is the significance of Lucilia cuprina?
Lucilia cuprina is responsible for at least 90% of fly strikes in sheep, causing significant economic loss.
How can fly strikes in sheep be controlled?
Control measures include Mules operation, worm control, crutching, jetting, tail docking, breeding for resistance, treating strikes, removing carrion, and traps.
