Flagellates Flashcards
What is the class of flagellates that has a huge mitochondrion with circular DNA? What is that mitochondrion called?
Kinetoplasta
Kinetoplast
What are the two genera of Kinetoplastids that are of importance to animal health?
Trypanosoma
Leishmania
What are some general features of Kinetoplastids?
They have no cyst stage; there are trypomastigotes and amastigotes in the host
What are some of the general features of Trypanosoma?
Most are hemoflagellates
Cause disease called trypanosomiasis
Life cycle is indirect, with blood feeding insect as vector
What are the two groupings of Trypanosoma? What are they based on?
Stercoraria and Salivaria
They are based on the vector-mediated transmission form
What are the species of Stercoraria Trypanosomes we are concerned with? Are these pathogenic?
Trypanosoma theileri
Trypanosoma melophagium
Trypanosoma cruzi
NO, most are non-pathogenic except for Trypanosoma cruzi
_______ is a stercorarian trypanosome of cattle worldwide
Trypanosoma theileri
What is the vector of Trypanosoma theileri?
Tabanid flies; spread by contaminative transmission
_______ is the stercorarian trypanosome of sheep
Trypanosoma melophagium
What is the vector of Trypanosoma melophagium?
Sheep ked; wingless, blood sucking flies
______ is the only stercorarian Trypanosome that is considered a pathogen
Trypanosoma cruzi
American trypanosomiasis is caused by:
Trypanosoma cruzi
What is the vector of Trypanosoma cruzi? How does it spread this to the host?
Triatomine bugs
It proliferates in the hindgut/feces of the vector and is deposited on the skin of the host by defication
What are some of the ways that Trypanosoma cruzi can be passed to the host?
Defication by the vector
Blood transfusion
Ingestion of the Triatomine bug
Transplacental/transmammary routes
What is the general route of infection for Trypanosoma cruzi?
They infiltrate the blood as trypomastigotes, which infect host cells. They replicate as amastigotes. Mature back to trypanomastigotes and invade new host cells. Cycle repeats
What age do you usually see Trypansoma cruzi acute infections in dogs? What are the signs?
Less than 2 years old
USually see large lymph nodes, weakness, ataxia
How would you diagose the acute stage of Trypanosoma cruzi?
Examine the blood for trypomastigotes, which are C or S shaped and have a large kinetoplast
What does Trypanosoma cruzi chronic infection look like?
Foci of intracellular amastigotes are present.
Many develop into fatal dilated cardiomyopathy within 5 years
Dogs are asymptomatic until end stage heart failure
What are the species of organisms in the Salivaria group we are concerned about?
Trypanosoma congolense Trypanosoma vivax Trypanosoma brucei Trypanosoma evansi Trypanosoma equiperdum
How are the salivaria Trypanosomes transmitted?
Via bite of vector; they multiply in gut of the vector
Where is the infective form of the salivaria Trypanosomes located? In what fly?
Salivary glands
Tse tse fly
Most of the salivaria Trypanosomes are significant pathogens due to them being able to survive in the blood stream. Why can they do this?
Produce a glycoprotein that allows them to evade hosts immune system
What are the species that cause African Trypanomiasis?
Trypanosoma congolense
Trypanosoma vivax
Trypanosoma brucei (less common than previous two)
Trypanosomiasis in humans is referred to as:
african sleeping sickness
African sleeping sickness can be diagnosed by isolating trypanomastigotes from the:
Lymph nodes and CNS
What are the sylvanian trypanosomes that are of concern in the US?
Trypanosoma vivax
Trypanosoma evansi
Trypanosoma equiperdum
_____ is the trypanosoma that is currently in the Carribean islands and SA and affects cattle
Trypanosoma vivax
______ is the blood parasite that is the causative agent of surra
Trypanosoma evansi
Trypanosoma evansi can infect most mammals, but _____ and _____ are the principle hosts
Camels
Horses
What fly types transmit Trypanosoma evansi?
Horse fly, stable fly, and Tse tse fly
______ is a venereal disease of horses that is often called dourine
Trypanosoma equiperdum
T/F Trypanosoma equiperdum cannot occur in the US
FALSE; it can occur, it has just been eraditcated
How is Trypanosoma equiperdum transmitted?
Between male and female (copulation)
Between mare and foal (rare)
Lactogenically
What is the life cycle of Trypanosoma equiperdum?
PArasite multiples asexually at site of infection; localizes in the subcutaneous tisses until it gains acess to peripheral blood
Describe the three step process of Trypanosoma equiperdum infection
1: Parasite is localized to repro tract
2: Silver dollar plaques on chest/rump/flank. These are pathognomonic
3: Causes anemia and nervous system can be affected
How would you diagnose a Trypanosoma equiperdum infection?
detect and ID the parasite. Can be done with smears, wet mounts, or cultures of repro tract secretions
Treatment of Trypanosoma equiperdum?
NONE; euthanasia. Want to prevent re-introduction of this parasite
The two classifications of Flagelletes are Trypanasomes and _______
Leishmania
What are the species of Leishmania we are concerned with?
Leishmania infatum
What is the disease of Leishmania called?
Leishmaniasis
T/F Leishmaniasis is zoonotic
TRUE; has a wide range of hosts
_________ causes visceral leishmaniasis in dogs in North America
Leishmania infatum
Leishmania infatum life cycle is ____
Indirect
What vector is commonly used to spread Leishmania infatum?
Sandflies
How does the vector acquire LEishmania infatum?
Ingests macrophages with amastigotes. Parasites then multiply in the vector gut and promastigotes are inoculated when the vector feeds.
How does the host acquire Leishmania infatum?
Parasites from the vector invade local macrophages, multiply as intracellular amastigotes, which are then released and taken up by other cells. How the parasite migrates in teh body.
What are some signs associated with Leishmania infatum?
decreased endurance, weight loss, along with lymphadenopathy, skin lesion and cachexia, and deformed overgrowth of nails
What is the pathogenesis of Leishmania infatum?
It increases IgM/IgG production, which results in circulating immune complexes.
This contributes to glomerulonephritis, vasculitis, and polyarthritis.
Also results in T cell dysfunction and macrophage proliferation
T/F Infection with Leishmania infatum can mimick several other diseases including lymphosarcoma
TRUE
What is the definitive diagnosis for Leishmania infatum?
Detect and ID amastigotes in tissues (LN, skin lesions, etc.)
ELISA test is also available
T/F Once you cure Leishmaniasis the dog is immune for the duration of its life
FALSE; relapses occur in almost all forms of Leishmaniasis
Leishmaniasis treatment?
Not curative; it is zoonotic so euthanaisia is usually suggested
T/F Flea and tick collars can help prevent Leishmaniasis
TRUE; they repell sand flies which are the vectors for this disease
Cutaneous leishmaniasis is caused by _________ which is retained in small rodents
Leishmaniasis mexicana
What are the three forms of Leishmania mexicana?
Visceral, mucocutaneous, and cutaneous
Mucosoflagelletes are made up of:
Giardia duodenalis Giardia agilis Giardia ardeae Giardia microti Giardia muris Spironucleus meleagridis Histomonas meleagridis Tritrichomonas foetus Trichomonas gallinae Tritrichomonas blagburni Tritrichomonas vaginalis
Giardia duodenalis causes _______ AKA BEAVER FEVER
Giardiasis
What are the different genotypes of Giardia duodenalis and what do they effect?
A1: animals A2: Humans B: Humans C&D: Dogs E: Hoofed animals F: Cats
T/F NO humans have been found to be infected with C,D,F serotypes of Giardia duodenalis
TRUE; they have found animals infected with A and B though
T/F Giardia is one of the most common human intestinal parasites
TRUE
What is the life cycle of Giardia duodenalis?
Direct; cyst is ingested with food or water contaminated by feces
Cyst then excysts in the SI where it multiplies asexually.
Trophozoites are non-infective but the cysts passed in the feces are immediately infective
What is the most common source of infection for Giardia duodenalis?
Water that has been infected by feces
What is the main cause of signs associated with Giardia duodenalis?
The trophozoite attaches and detaches from the gut epithelium, causing villous atrophy, loss of brush border, and impaired absorption
What are some clinical signs?
Diarrhea, bloating, nausea
How do you diagnose Giardia duodenalis?
Fecal float in zinc sulfate; Giradia cysts will take up iodine
The cyst contents will also retract from the wall and form a crescent shape.
Treatment for Giardia duodenalis?
All extra label; Fenbendazole (pregnant bitches) Albendazole (DONT use in pregnants)
Name the other Giardia species and what they infect
Giardia agilis: amphibians
Giardia ardeae: birds
Giardia mircoti: voles and muskrats
Giardia muris: rodents
Spironucleus meleagridis is a disease of _______ and ______ but not chickens
Turkeys and gamebirds
What is the life cycle of Spironucleus meleagridis?
Direct; trophozoite is ingested with food or water recently contaminated with feces
Localizes in the duodenum and multiplies asexually
Trophozoite is shed into the feces
T/F The infective stage for Sprionucleus meleagridis is the cyst that is produced
FALSE; there is no cyst produced. IT is the trophozoite
What are some signs birds affected with Spironucleus meleagridis would display?
Sick bird with white, watery, foamy dropping
Treatment for Spironucleus meleagridis?
NONE
This is a flagellate that has a high mortality rate for turkey poults
Histomonas meleagridis
T/F Histomonas meleagridis also causes a disease in chickens
FALSE; they can be resevoirs though. Important to not house chickens and turkeys together
Histomonas meleagridis exists only in the _____ stage
trophozoite phase; NO CYST
What are the modes of transmission for Histomonas meleagridis?
cloaca drinking; can be picked up with contaminated bedding.
Survives for years in eggs of Heterakis gallinarium
Where do the trophozoites of Histomonas meleagridis localize?
Lumen of the Cecum of the turkey
What is the pathognomonic diagnosis of Histomonas meleagridis? What are some other classical signs?
Liver lesions
General sick bird appearance
_______ is a worldwide veneral disease of cattle
Tritrichomonas foetus
Tritrichomonas foetus is more common in ______ herd than ______ herds
beef
dairy
What is the transmission of Tritrichomonas foetus?
mechanical transmission during coitus
What are the clinical signs of Tritrichomonas foetus?
Bulls: asymptomatic
Cow: early embryonic death and abortion. Can rebreed in 2-6 months
What is the definitive diagnosis of Tritrichomonas foetus?
Schmegma from preputial scrapings or washings
What is the treatment of Tritrichomonas foetus?
No drugs available
Cull all cows that are open
Management practices to clean up herd
What causes canker in pidgeons and doves as well as Frounce in birds of prey and poultry?
Trichomonas gallinae
What is the transmission of Trichomonas gallinae? What stages are present?
Oral-oral
Trophozoites are transmitted, no cyst stage
What is the habitat of Trichomonas gallinae?
epithelial surface from oral cavity to crop, in sinueses, and viscera
What are the signs of Trichomonas gallinae?
Anorexic, as well as dysphagia, weight loss, and difficulty breathing
_____ is the feline trichomoniasis
Tritrichomonas blagburni
What does Tritrichomonas blagburni cause?
Colitis; large bowel disease
causes an increased frequency of defication and cow-pie like stools
Can cause an inflammed painful anus
Where is Tritrichomonas blagburni most common?
Shelters, cat colonies, and multi-cat households
______ is the most common STD in the US right now?
Tritrichomonas vaginalis
T/F Tritrichomonas vaginalis causes clinical signs in men and women
FALSE; Tritrichomonas vaginalis is asymptomatic in males
