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187 Cards in this Set

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  • Back
Cankors refers to ?
TRICHOMONAS gallinae in doves, turkeys, pigeons
Pathology of what parasite?
*lesions in, rectal mucosa; ulcers are flask shaped
*can have liver dz, absc.
*life thr. if lung or CNS involved (brain abscess)
Pathology of Ent. histolytica
*lesions in, rectal mucosa; ulcers are flask shaped
Example of protozoans with flagella:
trichomonads, Giardia, Histomonas (pleomorphic - flagellated form is in cecal lumen)
Example of protozoans with cilia:
Balantidium coli
Example of protozoans with undulating membrane (also used for transportation)
trypanosomes, trichomonads (not histomonas)
T or F: All protozoans divide by binary fission.
3 methods of asexual reproduction:
1. binary fission
2. multiple fission or schizogony
3. budding
What is longitudinal and transverse binary fission?
just the way the cells divide ie. longitudinal is along longest axis
2 methods of sexual reproduction
1. conjugation
2. syngamy
schizogony is characteristic of ____?
what is it?
Apicomplexa - nucleur division results in formation of many new organisms
note: Apic. also do syngamy (sexual)
What is conjugation?
temporary fusion of cells with exchange of nuclear material; followed by binary fission
What is syngamy? What happens next? (characteristic of?)
union or fusion of sexually distinct gametes to form zygote (or oocyst); (e.g. apicomplexans; macro & microgametocytes)
Do giardia do direct or indirect transmission?
Direct transmission; no intermediate host
Main protozoan parasite in bovine?
Where does T. foetus reside in bull?
preputial cavity of bull
Clinical signs of T. foetus infection in bull?
*BULLs usually assymptomatic
(mostly in older bulls)
Where does T. foetus reside in cow?
Pathology of Trich. foetus in cow? pregnant cow?
- early abortion
- chronic endometritis; can lead to perm.sterility
Which parasite can cause LYMPHOID INFLAMMATION &
What drug prohibited for use in food producing animals?
Treatment for Trich. foetus (in bull)?
*cull bull w/parasite >3 yrs. old
Is Trich. foetus an intracellular parasite?
yes; there's cellular infiltration thats why causes fibrosis, endometritis
Young birds are exp. weight loss, ruffled feathers, and diff. breathing and mucoid nasal exudates. What parasite resp.?
Trichomonas gallinae
Vaccination for Trich. foetus intended for?
TrichGuard® and TrichGuard®V5L
Intended for cows;
-given annually
-produces immunity 4 weeks prior to breeding.
(skeptical of its effectiveness)
Mode of transportation for Trich. foetus ?
flagella; undulating membrane
Aerobic or anarobic?
NO; anarobic
TRICHOMONAS GALLINAE infects what hosts?
mainly doves, pigeons, and raptors; also turkeys, pheasants, finches, java sparrow & canaries, chickens (rare); dz of young birds

T-G-C-F (try getting cheap flights)
Common names for Trichomonas gallinae (in doves or pigeons) ?
AVIAN TRICHOMONIASIS, “CANKER” (in doves or pigeons)
Common names for Trichomonas gallinae (raptors) ?
TRANSMISSION of Trichomonas gallinae (4)
-adult to squab via pigeon milk
- beak to beak
-FECAL-ORAL (contaminated water, grain, a/o bedding)
-raptors get from eating pigeons infected = "frounce"
Clinical signs of Trich. gallinae
Depr., salivate exc., emaciation, listless, ruffled feathers, dull, diff. breathing/swallowing, may die of starvation
Pathology of Trich. gallinae
MUCOSAL LESIONS in mouth, caseous necrotic masses in dig.tract, inflam.,,if chronic...necrotic lesions in the liver, spleen, pancreas, heart, lungs
Drugs for treating Trich. gallinae?
Dimetridazole, Metronidazole (Flagyl), Copper sulfate, Enheptin, Carnidazole..also feed/fluids
DNA HOMOLOGY (based on a very conserved region of the genome)
TRICHOMONAS CANISTOME occurs where in dogs?
not pathogenic; in mouth of dog
Turkey; in addition to CHICKENS & OTHER BIRDS (QUAIL)
HISTOMONIASIS dz also known as ?

Cyanotic discoloration of the head has caused the disorder to be named "blackhead".
Morphology of Histomonas Meleagridis?
Pleomorphic: 1.) amoeboid form in int./cecal lumen (flagella) 2.) in tissues (no flagella; in clusters) 3.) transitional form - enclosed in dense membrane
can cats get infected with trichomonas spp.?
(Tetratrichomonas felistomae) only cats with gingivitis and those
immuno-compromised e.g. cats with FIV, FeLV or FIP
Are cats susceptible to trichomonas felistomae if have stomatitis due to other causes (not gingitivitis or FIV etc)?
NO....(see page 12 long notes)
How is Histom.meleagridis transmitted?
1. transm. mostly in embr. eggs of cecal nematode Heterakis gallinarum which dev. to L2 (inf. stage) after excr.
2. Sometimes transm. directly by contact w/inf. birds.
The flagellated form of Histom.meleagridis reside in what part of bird? When? (like what is stage before this?)
in cecal lumen when nematode egg "hatch"
Does Histom.meleagridis have cyst stage?
No evidence in vivo of cyst; although some reports of finding cyst-like stage in culture
Pathology of Histom.meleagridis ?
What tissues does it proliferate in?
The principal lesion are in bird cecum and liver (via tissue form)
Clinical signs of Histom.meleagridis ?
yellow droppings, ruffled feathers, skin on head black which is associated w/sec.infections (e.g. E.coli, etc.)
Treatment of Histom.meleagridis? (2); for nematode host? (2)
*Fenbendazole (best), metronidazole (non-food only).
*Also piperazine or phenothiazine can treat Heterakis (nematode) infection
How does Histom.meleagridis reproduce?
binary fission
T or F: Histomonas meleagridis has a indirect life cycle.
False: Direct, but unique. . Inf. occurs via eggs of nematode, Heterakis gallinarum (cecal worm), but it is paratenic host; histomonas can transmitted directly..fecal-oral somehow
Giardia lamblia endemic area?
Definitive hosts for Giardia lamblia (5)
i) Humans
ii) Dogs
iii) Cattle
iv) Sheep
v) Beavers
Intermediate hosts for Giardia lamblia
None, direct life cycle
Infection route/Infectious stage for Giardia lamblia
i) Ingestion of cysts usually by contaminated drinking water
ii) Cysts are the infective stage
Life cycle for Giardia lamblia
Hum./Dog/Sheep/Cattle/Beaver shed cysts -> ingested by another host via contam. water -> excyst. in SI -> 2 trophs released -> as pH incr., cholest. decr, less fluid GI so encyst etc.
Which assemblages of Giardia lamblia are zoonotic?
A1, A3, B
Which assemblages of Giardia lamblia are NOT zoonotic?
A2, C-G
Giardia trophs. multiply via ?
How often?
longitudinal binary fission (every 12 hours)
Prepatent period for Giardia is?
PPP is 6-8 days.

Interval btw. infection of individual by parasitic organism and first ability to detect from that host diagnostic stage of organism (e.g. egg in feces).
Morphology of giardia troph?
How nuclei?
How many flagella?
Fragile, motile, feeding stage, pyriform shape, 2 nucleus, 2 median bodies (unique to giardia), 4 pair flagella, axoneme (microtubules which make up flagella),
Which is feeding stage of Giardia?
pyriform means?
pear giardia troph
The most common flagellate found in humans (digestive tract)
Do ENTAMOEBA spp. have cyst stage?
What triggers giardia cyst to form?
Feces entering colon begin to dehydrate and encystment occurs.
Cholesterol deprivation trigger?
Clinical signs of giardia infection? Be specific.
Diarrhea, weight loss, dry skin, poor coat, growth ret., sulfur smelling flatulance
(feces may be pale watery w/fat..gall bladder and secretion of digestive enz. can be affected)
T/F Most protozoa are parasitic
FALSE. Most protozoa are commensals or are free-living. A third are parasidic
What is Schizogony?
Schizogony is when the nucleus divides several times before the cytoplasm divides.
Diagnosis of Giardia?
Fecal float (detects cyst), endosc.duod. aspiration, ELISA, IDEXX snap test
How does IDEXX snap test detect giardia?
Detects proteins (cyst wall protein) released during encystation, swab fecal float, mix w/conjugate, add to mixture to contraption
Giardia treatment for cats/dogs
Fenbendazole (Panacur), metronidazole (has safety concerns in cats)
Cause of Amebiasis (Amoebic dysentery) in humans?
Entamoeba histolytica = (Amoebic dysentery)
Is Entameoba histolytica zoonotic?
Yes, humans, primates
Entameoba invadens zoonotic? hosts?
No, only reptiles
E.bovis host? pathology?
cattle, non-pathogenic entameoba sp.
Is Entameoba coli pathogenic?
No; exists as a commensal parasite in human GI tract; food vacuoles of Ent.coli do NOT contain RBC's
How does one differentiate btw. different Entameoba spp.?
Differentiation of species by number of nuclei in mature cyst (metacyst) or in trophozoite;
as the number of nuclei varies greatly btw. species.
Giardia treatment for ruminants
Giardia treatment for ruminants = Fenbendazole
How many nuclei does Entameoba histolytica troph have?
How many in mature cyst?
*single nucleus with distinct central endosome in troph
*4 nuclei with " in cyst
Transmission of E. histolytica
Fecal-Oral contamination
Have many trophs do ENTAMOEBA cysts release upon excystation? Where?
4 trophs released into SI.
Where does Ent. histolytica reside? (anatomical region)
E. histolytica resides in crypt of large intestine, but have been found elsewhere ie. liver, lung, brain
Trophs of ENTAMOEBA divide via? where?
binary finssion in crypts of cecum and colon (large int.)
Diagnosis of Ent. histolytica?
Can troph be seen in feces?
trophs usually seen in diarrhea, cysts in harder stuf, diagnosis via ELISA, PCR, IFAT, hemagl.test
Treatment of Entamoeba?
ENTAMOEBA life cycle (what are stages?)

Where is troph?
Trophozoite (divide by BF in LI.;cecum) > Precyst > Cyst > Metacyst (excreted) > Metacystic Trophozoite
what is metacyst of ENTAMOEBA?
where do they fit in life cycle?
Metacyst – Quadrinucleate cyst. Semi-formed stool contains precyst and cyst but Metacyst are most common.
What insects have been shown to occassionally act as vectors for certain Entamoeba spp.? (e.g. E.invadens)
cockroaches & house flies
Which is larger in Entamoeba, cyst or the trophozoite?
Entamoeba trophozoite is larger (with extensive pseudopods)
What might one find in food vacuole of Ent.histolytica which has infected human?
What zoonotic parasite is norm. commensal of, has very WIDE host range, can cause dysentery, lg.troph w/kidney shaped macro- nucleus?
Balantidium coli
Pathology of Balantidium coli
*can be asymptomatic
*but if other org. initiates lesion, B.coli may invade = deep ulcers in colon etc.
* Balantidium dysentery
Hosts of Balantidium coli (8)
Human, swine ('farmers' get from pig pooh), birds, rats, g.pigs, dog, roach, primates (more rare in cats and dogs_
Transmission of Bal. coli
T or F: Balantidium coli usually invade mucosa.
False, rarely unless lesion initated by other organism
Which of following uses paratenic host?
A. Giardia
B. Balantidium Coli
C. Histomonas
D. Trypanosomes
E. Trichomonads
C. Histomonas used cecal worm (heterakis gallinarum) as paratenic or transport host (nonessential)

Name example of facultative parasite:
House fly: organism that is capable of living either a free or parasitic existence
At turkey necropsy, find target-shaped circular areas of necrosis in liver and caseous sores in ceca. What is likely diagnosis?
a. Ascaridia gallinae
b. Histomonas meleagridis
c. Eimeria meleagridis
d. Tyzzeria pernicoiosa
e. Trichomonas gallinae
b. Histomonas meleagridis - most common in turkeys
Which animals are carriers of T. foetus?
Bulls (not cows)
This parasite can be found in the urine and in sediment and occurs in MOUTH of dog
Trichomonas canistomae
What's this?
Trichomonas gallinae
Balantidium coli cyst (40-60um): notice the kidney-shaped macronucleus (also in troph)
Fenbendazole (aka Panacur) used to treat ?
Histomonas, Giardia, and Pentatrichomonas (not T.foetus)
What hemoflagellate can be transmitted in fruit juice? What stage of life cycle in juice?
Stercorian (=feces) Trypanos.; epimastigotes from crushed "kissing-bugs"; NOT Leishmania
w/Trypan.cruzi, ingested which form (morphology)?
Trypomastigote forms are ingested when kissing bugs feed on vertebrate host
~this is important distinction, but can also take up amastigote
What is Romana's sign?
Symptom of Chagas' dz, (palpebral edema & conjunctivitis); due to rubbing the organism into the eye.
w/Trypan.cruzi, what form are passed in bugs' feces & deposited on skin when bugs feed (usually around eyes or mouth)?
w/Trypan.cruzi, Metacyclic trypomastigote is passed in bug feces
What parasite?
w/Trypan.cruzi, what form undergoes binary fission in tissues of mammalian host?
change into AMASTIGOTE forms & reproduce in the tissues (like in Leishmania)
w/Trypan.cruzi, what form undergoes binary fission in insect host?
*w/Trypan.cruzi epimastigote multiplies in insect
(promastigote in Leishmania)
What is a "chagoma" ?
In Chagas' dz, "chagoma" is inflam. lesion dev. at site of inf. in skin; caused by parasite's initial mult. in subcut.tissues.
Transmission of Tryp.cruzi?
kissing bug feces, transplacental & transmammary in dogs, organ transplants, blood transfusions, ingestion of bug in fruit juice,
Initial pathology of Chagas' Disease in humans? Then?
initially induces fever, malaise, lymphadenopathy and hepatosplenomegaly, THEN CNS, intestinal, repro.tract involvement
w/Trypan.cruzi, what will trypomastigote become in IH?
Trypomast. -> Epimastigote & metacyclic trypomastigote forms are present in gut of Kissing bugs
Reservoir hosts for Tryp.cruzi?
A ton of RH...Possums, armadillos, raccoons, coyotes, rodents, bats, skunks
Affective treatment for Chagas' dz?
NO, Dogs vaccinated failed to dev. immunity; Nifurtimox™ (nitrofuran derivative); significant side effects
What form of Trypanosome is reportable dz?
T. equiperdum (Dourine = "unclean" in Arabic) must be reported to state or federal authorities immediately upon diagnosis or suspicion of the disease!
Transmission of Tryp. equiperdum (Dourine)?
Venereal transmission <-exclusively; stallions to mares is more common, but mares can also transmit dz to stallions.
Hosts for T. equiperdum (Dourine)
Mainly affects horses, donkeys and mules. Zebras have tested positive by serology, but there is no conclusive evidence of infection.
Diagnosis of T. equiperdum (Dourine)
report to auth.; send serology (serum, whole blood in EDTA and blood smears). sample under secure conditions
Treatment and control: of T. equiperdum (Dourine)
euthanasia; good hygine
Identify parasite in picture (of amastigote inside host cell)
Dog Liver

(T.cruzi not usually in liver of dog)
Identify parasite in picture of promastigote (which form in IH, regurgitated, then can invade macrophage in DH)
Leishmania promastigote (change to amastigote inside host cell)
Identify parasite in picture
Trypanosoma cruzi epimastigotes and trypomastigotes.
Dog Muscle
Ruminant Muscle
Poultry Cecum
causative agent of coccidiosis
Intestinal Apicomplexa
monoxenous means?
1 host, host specific
T/F All vertebrate trypanosomes are monoxenous.
FALSE. All vertebrate trypanosomes (except T. equiperdum) are heteroxenous.
Name 6 genera of Intestinal Apicomplexa
1. Cryptosporidium
2. Eimeria
3. Isospora (Cystoisospora)
4. Neospora?
5. Toxoplasma
6. Sarcocystis?
Note: Family Sarcocystidae includes (Toxoplasma, Sarcocystis, Neospora)
is the invasive stage within the oocyst (sporocyst).
Sporozoite is the invasive stage within the oocyst (sporocyst).
What is a "zoite"
MOTILE, banana or cigar-shaped cell.
Pointed at the apical end.
Represents the beginning and end point of the coccidian life cycle.
What 3 motile stages of Apicomplexans?
2. Tachyzoite
3. Bradyzoite
T/F All Apicomplexa are parasitic.
TRUE (check this)
Infective forms that are found in sporulated oocysts.
rapidly dividing zoite.
Tachyzoite = rapidly dividing zoite or merozoite (e.g. seen in Neospora, Sarcocystis, and Toxoplasma)
slowly dividing zoite.
Formation of Sporulated oocyst (sporocyst) with sporozoites that are contained within.
Schizogony =

What happens?
Schizogony = merogony: multiple internal fission (asexual division).

Sporozoites invade hosts' cells, where form merozoites - replicating via schizogony.
Gametogony or gamogony occurs when ?
Describe process:
Gametogony is when merozoite (finished schizogony) enters a new host cell and differentiates into gametes
Name the 2 immature gametes are "sex" attributed to each (check this)
* male (microgametocyte or microgamont)
* female (macrogametocyte or macrogamont).
Mature sex cells (check this)
Microgamete (male) and macrogamete (female) = Mature sex cells
Result of union of a microgametocyte (male) and a macrogametocyte (female)
Oocysts (resistant "spore" stage or zygote) passed in the feces of the definitive host.
What method of sexual reproduction used by gametes during union etc.?
syngamy (obviously not conjugation)
Are bradyzoite and tachyzoites dividing inside or outside of host cell? or inside cyst?
check this...but they considered motile stages so..the tissue involved is spp. dependent
Where does SPOROGONY occur?
Usually occurs outside of the host (in the feces)..except with Cryptosporidium & Sacrocystis
What structure on sporozoite (of Apicomplexa) allow to enter host cell with ease?
Apical complex consisting of rhoptries (sacs containing enzymes) and conoid (cone of fibers) at anterior end; apical complex aids in entering host cell!
What disease? (be specific)
Mucocutaneous form of Leishmania = sloughing seen on nose & ears (cartilage) of dog, humans; form also in rodents, wild animals
Reservoir vs. definitive host:
Reservoir can be definitive host if lives long enough; just refers to wild species which carries dz from which it can inf. humans or domestic spp.
Name 2 examples of pleomorphic protozoans::
1. Histomonas Meleagridis (birds)
2. Trypanosomes
IN Trypanosome, ___ is an extension of the mitochondrion (it contains DNA); lies adj. to parabasal body from which ___ emerges.
kinetoplast is an extension of the mitochondrion (it contains DNA); lies adj. to parabasal body from which FLAGELLA and UNGULATING membrane emerges
Aid Trypanosome in mobility:
flagella which is attached to undulating membrane
How does trypanosme multiply or reproduce?
binary fission
Cause of Chagas' disease?
Trypanosoma cruzi
3 forms of Trypanosome?
1. Amastigote
2. Trypomastigote
3. Epimastigote (not in Leishmania)
___ form of Trypanosme found in mammals.
Trypomastigote form is found in mammal hosts (DH); has long undulating membrane & flagellum is present. ~Dominant form esp. in T.cruzi (not Leishm.)
(Amastigote also found in mammalian host.)
___ form of Trypanosme found in insects.
Epimastigote form is found in insects.
(Promastigote in Leishmania)
What form of Trypanosome is this?
amastigote form with a nucleus (N) and remnant of flagella (RF)) in the mammals.
What are three intermediate hosts of Trypanosomes?
1. tsetse fly (African Trypan.)
2. kissing bugs (T.cruzi)
3. triatome
cause movement by flexing and gliding (e.g., apicomplexans).
subpellicular microtubules aid mov't in apicomplexans
2 major genus in Order Trypanosomatida

Hint: these are hemoflagellates
What dz (if chronic) can lead to CNS manif. & myocardial involvement (dilated cardiomyopathy & ventricular arrhythmias)?
Chagas' disease (Tryp.cruzi)
3 clinical forms of Leishmania?
Most serious?
1. cutaneous
2. mucocutaneous
3. visceral (most serious)
Life cycle for Leishmania direct OR indirect?
indirect b/c has intermediate host
Intermediate host for Leishmania
Found in Ruminant Blood?
w/Leishmania, sandfly ingest what form of parasite with blood- meal?
w/Leishmania, amastigote becomes ___ in sandfly gut?
Has visceral form of Leishmania been reported in US?
not in humans, but in fox hounds
What form of leishmania characterized by: Dermatitis, nonulcerative nodules ("comedones"), plaques, lymphadenopathy, mucosal (gastroenteritis) may occur w/HIV+ patients
Diffuse Cutan. Leishmaniasis
~mucosal (gastroenteritis) may occur w/HIV+ patients; but char. by absence of visceral involvment
Amastigote form of Leishmania is found where? What hosts? (biological or intermediate)
w/Leishm., amastigote multiply intracellularly in mammalian host cells & ingested by sandfly; so appear in both biological and intermediate.
What parasidic dz (be specific) named: post-kala-azar dermal "leishmanoid" in India?
VISCERAL Leishmania in humans: “Kala-azar” = “Black fever” (Hindi)
T or F: All Trypanosome use intermediate host
~False: all do use IH; EXCEPT T. equiperdum (Dourine)
What form of leishmania char. by: reported in humans, dogs, rodents & wild animals. Ulcers; sloughing of cartilaginous tissues (NOSE)?
Mucocutaneous form of Leishmania = sloughing seen on nose & ears of dog, humans
What form of leishmania char. by: IM process due to an exc., non- protective Ig resp. = immune-complex depos. causes vasculitis, arthritis & thrombocytopenia?
Diffuse Cutaneous Leishmaniasis: immune-mediated process; excessive, non-protective immunoglobulin response
What form of leishmania char. by: Chronic wasting, exer.intol., anorexia, lameness, lymphadenopathy, epistaxis (nose bleeds), nonreg., anemia, and nonpruritic skin lesions?
Visceral form of Leishmania: fatal in humans and animals
(although no human cases rep. in US)
What form (morphology) of Leishmania is infective to mammalian host?
promastigote regurg. by sandfly when getting BM and inf. mammalian; where can then infect macrophages!

BM = bloodmeal
T or F: Aside from sandfly, no other IH of Leishmania has ever been reported.
False: Researchers have shown that “day feeding midges” (Lasiohela spp.) can be biological vectors & b/c isolated promastigotes (so ingesting amastigote and becomes promastigote inside like sandfly)
“Leishmanoid” dermal lesions of face (of humans) can contain thousands of ____?
contain thousands of amastigotes.
How might one isolate leishm.parasite from mammalian host? What parts of body?
skin scraping, biopsy (demonstration of amastigotes in spleen pulp, lymph nodes, bone marrow, liver, blood smears)
Transplacental transmission reported in humans and dogs in what disease?
Visceral Leishmania (L. infantum) , Stercorian Trypanosomes (T.cruzi)

(FYI: Neospara can., liver fluke, some toxocara, toxoplasma)
Transmission of Leishmania in dogs? (3)
1. sandfly
2. fighting (lesion contain amastigotes)
3. vertical transm. (transplacental)
Prevention of Leishmania?
Scalibor necklace (repels sandfly)
Treatment for Leishmania?
not really effective, but dev. FML vaccine in Brazil (canine prophylaxic Leishmune vacc.); Amphotericin B may help w/visc.form; heat surgery?
Diagnoisis of Leishmania? (3+3)
biopsy, skin scrape, send serum out (PCR, ELISA, Western blot)