Lab Exam 2 Flashcards
1
Q
What is the common name for Dipylidium caninum?
A
Double-pored or cucumber seed or flea tapeworm
2
Q
DH of Dipylidium caninum?
A
Dogs, cats, and humans sometimes
3
Q
IH of Dipylidium caninum?
A
Fleas
4
Q
What is the site of infection for Dipylidium caninum?
A
Adults in the small intestine
5
Q
Where are the germinal pores located on Dipylidium caninum?
A
The pores are on the lateral margins
6
Q
What is unique about the rostellum of Dipylidium caninum?
A
It’s retractable
7
Q
What is the infective stage to the DH for Dipylidium caninum?
A
Ingestion of a flea containing cysticercoids
8
Q
When diagnosing Dipylidium caninum, what can we look for?
A
Egg packets
9
Q
What are the signs and pathogenicity of dipylidium caninum in heavy infections?
A
Chronic enteritis - abdominal discomfort and vomiting
Anal irritation may cause scooting, but most likely it would just be impacted anal glands
10
Q
What is the size of a Dipylidium caninum egg packet?
A
120-200 microns
11
Q
What is the size of an individual Dipylidium caninum?
A
35-60 microns
12
Q
What can you see in the eggs of Dipylidium caninum?
A
Hexacanth embryo
13
Q
Common name for Taenia spp.?
A
Armed tapeworm (except T. saginata)
14
Q
What is the DH for Taenia?
A
Carnivores
15
Q
What is the IH for Taenia?
A
Vertebrate prey species
16
Q
Site of infection for Taenia spp.?
A
Adults in small intestine
Metacestodes in a variety of organs and tissues in IH
17
Q
Identification of Taenia?
A
Proglottids in the feces or attached to the hair coat
- the proglottids are more or less rectangular
- they have a single genital pore
18
Q
Can you find Taenia eggs in feces?
A
Yes, but the proglottid has to rupture first
19
Q
What does a Taenia egg look like?
A
25-40 microns in diameter Brown with thick shell wall Radial striations in the shell wall Contains hexacanth embryo Spherical
20
Q
Anoplocephala perfoliata DH?
A
Equine
21
Q
Anoplocephala perfoliata IH?
A
Oribatid mites
22
Q
Location of Anoplocephala perfoliata in equine?
A
Cecum at the ileocecal junction
23
Q
Does Anoplocephala perfoliata have a rostellum?
A
No, it has larger suckers in order to compensate
24
Q
What stage of Anoplocephala perfoliata is infective to a horse?
A
They ingest a mite with a cysticercoid
25
What is an easy way to identify an adult Anoplocephala perfoliata?
The lappets under the scolex
26
What does a mite need to ingest in order to progress the life cycle of Anoplocephala perfoliata?
An egg containing a hexacanth embryo
27
What are common clinical signs of Anoplocephala perfoliata?
Persistent diarrhea, intussusception (ileum goes into the cecum) and colic
28
What is the pathogenicity of Anoplocephala perfoliata?
It interferes with the function of ileocecal valve through ulceration and inflammation
29
What is the preferred diagnostic test for Anoplocephala perfoliata?
ELISA test
30
Why is a single negative test not diagnostic for Anoplocephala perfoliata?
The eggs are not always found during flotation. They're irregularly produced and the proglottid has to rupture
31
Describe an Anoplocephala perfoliata egg.
65-80 microns in diameter
Irregularly shaped with round corners
Contains a pyriform apparatus with a hexacanth embryo
32
What is an mnemonic for the basic lifecycle of Order Digenea?
Every - Month - She - Really - Can - Menstruate - Abundantly
Egg - Miracidium - Sporocyst - Redia - Cercaria - Metacercaria - Adult
33
What is the common name for Fasciola hepatica?
Liver fluke - liver rot in sheep
34
What is the DH for Fasciola hepatica?
Sheep, cattle, goats, and other ruminants
35
What is the IH for Fasciola hepatica?
Aquatic snails
36
What is the site of infection for Fasciola hepatica?
Adults in bile ducts
| Immatures migrate throughout the liver parenchyma
37
What is considered the most common liver fluke in domestic animals in the US?
Fasciola hepatica
38
Are the eggs of Fasciola hepatica immediately infective when passed in the feces?
No
39
What stage of Fasciola hepatica will an aquatic snail (IH) ingest to further the LC?
Miracidia
40
What stage of Fasciola hepatica is infective to the DH?
Metacercariae (ingestion of infected vegetation)
41
Does Fasciola hepatica need to be in the water to survive?
No, it can be on the waters edge
42
What is the pathogenicity of immature Fasciola hepatica?
Necrosis and anemia due to migration and feeding of the immature flukes through the liver parenchyma
43
What can migration of Fasciola hepatica cause?
Replication of Clostridium novyi
44
What is the pathogenicity of adult Fasciola hepatica?
Anemai and thickening of the bile ducts to feeding of adult trematodes
45
Describe an adult Fasciola hepatica.
Up to 3 cm, leaf-like, brownish
Broader anterior than posterior
Anterior cone-shaped projection with oral sucker
Also has a ventral sucker
46
Describe a Fasciola hepatica egg.
130-150 microns by 63-90 microns
yellowish-brown
indistinct operculum
47
What is the preferred diagnostic method for finding Fasciola hepatica?
Fecal sedimentation or FlukeFinder is preferred
| - undifferentiated embryo makes them heavier
48
What is the common name for Giardia duodenalis?
Giardiasis or beaver fever
49
What is the host of Giardia?
Wide range of vertebrates depending on Giardia assemblage
| - Domestic and wild mammals, birds, amphibians, lizards, rodents, etc.
50
What is the site of infection for Giardia?
Small intestine
51
What is a Giardia trophozoite?
The actively motile feeding stage
52
What is a giardia cyst?
Not moving
Offers environmental resistance
This is the stage that goes into the water
53
Giardia trophozoites are only found in what type of sample?
Fluid fecal sample
54
Giardia trophozoites will be found in what kind of sample?
can be found in diarrhea, but are more likely to find trophozoites
you can find these more in dried feces
55
What is the highly refractile organelle in Giardia? What is its function?
Median bodies
| Probably has to do with ventral disk formation
56
What are the flagella of Giardia supported by?
Axistial
| - internal structure that provides central support
57
What do Giardia trophozoites due in the intestinal tract?
They live on the surface and they blunt the villi - leads to malnutrition
58
When do Giardia cysts form?
As the intestinal contents are moving out of the host and into the external environment
59
How many nuclei are in young Giardia cysts?
| How many nuclei are in old Giardia cysts?
young - 2
| old - 4
60
What does Giardia use to attach to the intestinal wall?
Ventral disc
61
How many flagella does a Giardia trophozoite have?
8
62
What kind of LC does Giardia have?
Direct = fecal-oral
63
How can someone become infected with Giardia?
Ingestion of cysts from food, water, hands, fomites, etc.
64
Giardia PPP?
1-2 weeks
65
How do Giardia trophozoites replicate if there's only one?
They're hermaphroditic. They split down the middle (binary fission) and make more trophozoites
66
What is the pathogenesis of Giardia?
Trophozoites cover the epithelium and can cause acute focal inflammation and increased mucus production.
Villous atrophy can be common - maldigestion and malabsorption
67
In acute to chronic Giardia infections, what clinical signs do we see?
Pale, pasty semi-formed, foul-smelling stools
Intermittent diarrhea
Vomiting in dog
Migrate into bile duct causing biliary inflammation and or obstruction (heavy infection)
68
How doe we diagnose Giardia?
Ag detection test - detects cyst wall protein
- only use with clinical signs (diarrhea)
After treatment, retest with centrifugal fecal flotation (not the antigen)
69
What is the preferred flotation medium for Giardia?
Zinc sulfate with centrifugation (least harsh, doesn't suck water out of the cyst and distort it like others do)
70
Describe a Giardia cyst.
```
9-13 microns by 7-9 microns
Elliptical
Thin, smooth wall
2-4 nuclei
Axostyle (intracytoplasmic flagellum)
Comma-shaped median bodies
```
71
When can Giardia trophozoites be found within 30 minutes of collection?
When doing direct saline smear of fresh diarrheic feces or when doing a duodenoscopic aspirate
72
Describe a Giardia trophozoite.
Bilaterally symmetrical with a tear-drop or pyriform shape
2 nuclei
8 flagella
Rod-like median bodies (posterior to the nuclei, stain densely, highly refractile when unstained)
Concave adhesive dish that gives them a clown or monkey face
73
What kind of motility do Giardia trophozoites have?
Falling leaf motility
74
What stage do Trichomonads lack that are found in Giardia?
Cyst stages
75
What is the causative agent of tritrichomoniasis?
Tritrichomonas foetus
76
What is the host for Tritrichomonas foetus?
Cattle
77
Site of infection for Tritrichomonas foetus?
Cows - repro tract
| Bulls - prepuce (primarily)
78
What kind of LC does Tritrichomonas foetus have?
Venereal (direct) transmission
| Bulls are subclinical carriers; at least 6-8% infected
79
How many flagella does Tritrichomonas foetus have?
Tri = 3 flagella
80
What is the pathogenesis of Tritrichomonas foetus?
Presence and multiplication of parasites damage host tissue and cause inflammation
81
What can Tritrichomonas foetus do, that has an economic impact in regard to reproduction?
It invades the placenta and fetus and results in abortion
82
How do we diagnose Tritrichomonas foetus?
Visualizing or detecting trophozoites by using smegma from a bull or vaginal secretions from a cow
83
What are the different diagnostic techniques used for Tritrichomonas foetus?
Direct smear onto slide and visualize organisms (FYI: rare to see organisms without culturing first)
Culture in specific media pouch and then visualize
PCR culture pouch contents following incubation (send it to lab and they will try to detect the DNA through PCR)
84
What is the typical sign of Tritrichomonas foetus infection?
Lots of open cows
85
How does trophozoite movement differ between Tritichomonas foetus and Giardia?
Giardia:
- concave ventral disc
- sluggish
- falling-leaf; herky-jerky
Tritrichomonas foetus:
- undulating membrane
- forwardly progressive (have to chase it to keep up with it)
86
What disease is associated with Trypanosoma cruzi?
Chagas disease
87
What is considered to be the reservoir to the arthropod host throughout Latin America?
Dogs
88
What are the hosts of Trypanosoma cruzi?
Wildlife reservoirs (opossum, armadillos, rats, raccoons, wild canids)
Dogs
Humans
89
Site of infection for Trypanosoma cruzi?
Blood in early course of infection
| Later in variety of tissues, especially cardiomyocytes (heart tissue)
90
What is the IH for Trypanosoma cruzi?
Triatomines (kissing bugs)
91
How can a DH be infected with Trypanosoma cruzi from a kissing bug?
Stercorarian from the bug or ingestion of the bug
92
What are modes of transmission for Trypanosoma cruzi?
Transplacental, blood transfusion/organ transplant and food-borne (in Latin America)
93
What stage of Trypanosoma cruzi is infective to the kissing bug?
Metacyclic trypomastigotes
94
What is the pathogenesis of Trypanosoma cruzi?
Cell damage as trypomastigotes rupture from host cells, especially cardiac muscle cells, causing inflammation/damage
95
What are symptoms of Chagas disease that are only found in dogs?
Chagoma and Romanas sign
96
What are the clinical signs with acute phase Trypanosoma cruzi?
Lethargy, generalized lymphadenopathy, slow capillary refill/pale mucous membranes, syncope, tachyarrhythmia, L&R sided heart failure, enlarged spleen and liver, death
97
What are the clinical signs with indeterminate chronic phase Trypanosoma cruzi?
No clinical signs, parasitemia undetectable
| ECG usually normal, exercise may induce arrhythmias
98
What are the clinical signs with determinate chronic phase Trypanosoma cruzi?
ECG abnormalities become prevalent
Anemia, myocarditis, intermittent fever, enlargement of heart, weakness, exercise intolerance, syncope, right sided chamber failure, death
99
How do you diagnose Trypanosoma cruzi?
It's difficult, you use suspicion and then try to confirm
| Know if you're in an endemic area and know if the animal has travelled to an endemic area
100
Can you diagnose Trypanosoma cruzi with blood/buffy coat smear in acute phase?
Rare trypomastigotes
101
What is the gold-standard diagnostic technique for Trypanosoma cruzi?
Clinical signs and positive serology
| - PCR assay (specific, reduced sensitivity in chronic infections)
102
Hosts of Leishmania?
Mammals and sand flies
103
Site of infection for Leishmania?
Macrophages of host tissues, skin, spleen, liver, bone marrow, mesenteric lymph nodes
104
Pathogenesis of Leishmania?
Cell damage as amastigotes rupture from host cells --> inflammation
105
IH for Hepatozoon americanum?
Canids
106
DH for Hepatozoon americanum?
Gulf coast tick
107
Site of infection for Hepatozoon americanum?
Leukocytes and skeletal and cardiac muscle
108
Distribution of Hepatozoon americanum?
Endemic in states along Gulf coast, is expanding northward
109
What is unique about the primary route of transmission for Hepatozoon caninum?
The dog ingests the tick, not just the tick feeding on the dog
110
What does the Gulf Coast tick contain that is infective to dogs for Hepatozoon americanum?
they contain sporozoites in the hemacele (not the mouth parts)
111
What does the tick need to ingest to become infected with Hepatozoon americanum?
Gamonts (gametocyte in leukocytes)
112
What is the pathogenicity of Hepatozoon americanum?
Schizogony in muscle tissue --> inflammation
| Periosteal bone proliferation - unknown mechanism
113
What are the clinical signs of Hepatozoon americanum?
Fever, lethargy, ocular discharge, gait abnormalities, lameness, muscle atrophy, wasting, often fatal (sometimes), and chronic
Increase in the bone opacity is the periosteal bone proliferation
114
IH for Hepatozoon canis?
Canids
115
DH for Hepatozoon canis?
Brown dog tick/kennel tick
116
Why does Hepatozoon canis cause anemia?
Schizogony in bone marrow, liver, spleen, gut lymphatics
117
Where can you see gamonts of Hepatozoon canis?
Readily found on blood smears (< or = 100% WBC)
118
Does hepatozoon canis have transplacental or transmammarial transmission?
Transplacental transmission
119
What are diagnostic techniques for Hepatozoon canis?
blood smear (gamonts), CBC (anemia), and PCR
120
What are the diagnostic techniques for Hepatozoon americanum?
```
clinical signs, patient history, enzootic areas
blood smear (not sensitive)
gamonts very rare (0.1% in WBC)
Radiographs
CBC (neutrophilia, anemia)
PCR
Muscle biopsy (preferred diagnostic!!!)
```
121
What is the primary route of transmission for Hepatozoon canis?
Ingestion
