Intro to protozoans and flagellates

Define parasites

Organism that benefits in some way while the other (host) is harmed

Parasites are ________ living on or inside other ________

animals!

Endoparasites are _________ parasites that cause _____________

internal

Infections

Ectoparasites are ____________ parasites that cause ______________

External

Infestations

What are examples of endoparasites?

Protozoa and Helminths

What are examples of ectoparasites?

Arthropods

Define protozoan

Single celled eukaryotic organism

What is the significance of protozoans to human health?

Neglected tropical diseases (malaria etc)

What is the significance of protozoans to animal health?

Production: trichomoniasis, coccidiosis, tick fever

Companion: babesiosis, cytauxzoonosis

Which protozoans are of zoonotic potential?

Cryptosporidium, Giardia, Toxoplasma, Trypasonoma, Leishmania

What is a direct life cycle?

Parasite uses ONE host

What is an indirect life cycle?

Parasite uses TWO or MORE hosts

What are the 2 types of reproduction in protozoans?

Sexual and asexual (some can do both)

What is significant about sexual reproduction?

It allows for the potential for genetic recombination

What flagellates do we need to know?

Giardia and Tritrichomonas

Does giardia have a direct or indirect life cycle?

DIRECT

What type of reproduction does giardia have?

Asexual

Giardia is an ____cellular, intestinal parasite

EXTRA

Giardia is a common cause of what symptoms?

Diarrhea and weight loss

What are the hosts of giardia?

Dogs, cats, and humans

What is the life cycle of giardia?

Animals eliminate trophozoites/cysts —> cysts mature —> can then be ingested and infect another host

What is the trophozoite of Giardia?

The feeding/reproductive stage

What is the cyst of giardia?

The infective stage

What type of diarrhea does Giardia produce?

Soft mucoid feces, can be intermittent

What is the pathogenesis of giardia?

Trophozoites adhere to intestinal villi in the duodenum —> shorten microvilli and destroy enterocytes —> malabsorption of nutrients and hyper-secretion of mucus

How to diagnose giardia

Floatation

Direct smear of diarrhea

Antigen testing

What are strategies of prevention of giardia?

Improved sanitation

Avoid consumption of contaminated water/food

Vaccination (old)

Is giardia zoonotic?

There are different assemblages that some are zoonotic, some are host specific

What type of life cycle does Tritrichomonas have?

Direct

What type of reproduction does Tritrichomonas have?

Asexual

What is the morphology of Tritrichomonas?

Trophozoite

Pear shaped with flagella

What is the life cycle of Tritrichomonas?

Sexually transmitted, either located in the preputial mucosa or in the os cervix

What are the clinical signs of T. foetus?

Infected animals can appear healthy

Reproductive problems when bred to infected bull

What are the types of reproductive problems caused by T. foetus?

Temporary infertility, abortion, pyometra/mummification

What is the pathogenesis of T. foetus?

It secretes proteinases that alter the uterine environment

How do you diagnose T. foetus?

Direct identification

Culture material

PCR

What are the TXs for T. foetus?

No approved/effective TX

What are methods of prevention of T.foetus?

Testing/management, AI, vaccines, infected bulls should be culled

All bulls must be tested for T. foetus because it is a....

reportable disease