Equine Parasites and Diagnostics Flashcards
1
Q
The amount of clinical disease a horse will show depends on what 3 factors?
A
type of parasite involved number of parasites involved host defenses (young and debilitated animals more susceptible)
2
Q
What is the life cycle of the parasite?
A
eggs or larvae deposited in manure
eggs or larvae develop in the environment and swallowed while horse is grazing
larvae mature in horse’s digestive tract where they become egg laying adults
3
Q
What are the common signs of Internal parasites?
A
poor growth weight loss decreased feed efficiency colic diarrhea pneumonia death dull hair coat poor performance
4
Q
What are the important Internal parasites of the horse?
A
large strongyle (S. vulgaris, S. edentatus, S. equinus) small strongyle (Cyathostemes) roundworm (Ascarids) Bots (Gastrophilus spp.) pinworms (Oxyuris equi) tapeworms (Anoplochephala) threadworm (Strongyloides)
5
Q
What is another name for Strongylus vulgaris?
A
bloodworm
6
Q
Which Internal parasite is the most dangerous
A
Strongylus vulgaris
7
Q
What problems do S. vulgaris cause?
A
thromboembolic colic
various degrees of anemia
larval migration causes formation of aneurysms and infarcts of intestinal circulation
8
Q
What life cycle does S. vulgaris have?
A
direct
9
Q
Where does S. vulgaris larvae live?
A
in artery supplying blood to the intestines
blood clots form which block blood supply to the intestines
10
Q
What is the infective stage of S. vulgaris?
A
3rd stage
11
Q
What artery is associated with S. vulgaris?
A
cranial mesenteric artery
12
Q
What is the prepatent period of S. vulgaris?
A
200-332 days
6 mo
13
Q
How is S. vulgaris dx?
A
fecal float
necropsy (aneurysm of cranial mesenteric artery)
14
Q
How is S. vulgaris treated?
A
Larvae: ivermectin and moxidectin
Adults: fenbendazole and ivermectin
15
Q
What happens during the 3rd stage of S. edentatus?
A
migrate to the liver and become encapsulated and molt to 4th stage (~2wks(
16
Q
What happens during the 4th stage of S. edentatus?
A
larvae wander in the liver for 2mo, leave the liver by ligaments that hold liver in position, wander for months in connective tissue
17
Q
What is the prepatent period of S. edentatus?
A
11 mo
18
Q
Where is S. edentatus found?
A
in the lining of the cecum and colon
19
Q
Where does 3rd stage S. equinus undergo molt?
A
wall of the large intestine
20
Q
What happens after S. equinus molt?
A
bore into right half of liver
21
Q
How long does S. equinus stay in the right half of the liver?
A
6-7wks
22
Q
Where does S. equinus migrate after the liver?
A
enter the pancreas and abdominal cavity where they develop into adults. then reenter the lumen of the large intestine and mate
23
Q
What is the prepatent period of S. equinus?
A
9mo
24
Q
How is a strongyle infection dx?
A
fecal float
necropsy
25
How do you treat large strongyles?
ivermectin
| moxidectin
26
How often should you treat for large strongyles?
Q 6mo
27
What is the name of the small strongyle?
Cyathosotominae
28
What type of life cycle does Cyathostominae have?
direct
29
Where do Cyathostominae larvae live?
in gut wall of large intestine
30
Why is the Cyathostominae the internal parasite of highest concern?
encysted stage is not affected by dewormers
31
How long is the life cycle of Cyathostominae?
4-6wks
32
What are the symptoms of Cyathostominae infections?
colic
diarrhea
ill thrift (loss of body condition)
33
What is the common name of Oxyuris equi?
pinworm
34
Where do adult pinworms lay eggs?
around anus
35
What is the tell tale sign of pinworms?
bare patches around the tail and perineum (puritius ani)
36
How do you dx Oxyuris equi (pinworms)?
```
egg masses in perineal region
tail rubbing
eggs in feces (rare)
adults in feces
tape test
```
37
How do you treat Oxyuris equi (pinworms)?
moxidectin
piperazine
pyrantel
38
What is the common name of the Gastrophilius spp?
stomach bots
39
What are the 3 types of Gastrophilius spp?
G. nasalis
G. hemorrhoidalis
G. intestinalis
40
Where are G. nasalis eggs laid?
hairs of jawbone
| yellow
41
What is the life cycle of G. nasalis?
eggs laid on jawbone hairs (~5-6d)->migrate between molars of teeth (~several weeks) ->(molt and swallowed) migrate to duodenum
42
What is the prepatent period of G. nasalis?
9mo
43
Where are G. hemorroidalis eggs laid?
on lip hairs
44
What color are G. hemorroidails eggs?
black
45
What is the life cycle of G. hemmoroidalis?
eggs laid on lip hairs (~2-4d) -> burrows in mucus membranes ->migrate to stomach ->duodenum
46
Where are the eggs of G. intestinalis laid?
yellow flecks in fur (moisture in breath makes them molt)
47
What is the life cycle of bots?
eggs laid in fur (moisture in breath makes them molt) -> burrow in tounge (~1mo) ->go between molars -> stomach only
48
How do you dx bots?
see eggs on mane and hair
endoscopy of stomach
necropsy
knowing flies are in the area
49
How do you treat bots?
```
only wormers effective against insects kill bots
ivermectin
moxidectin
nits removed from hair by bot knife
warm water with insecticide added
```
50
What are the stomach worms?
Habronema muscae
H. microstoma
Draschia megastoma
51
Where is Draschia megastoma found?
in tumor like swellings in the stomach wall
52
What condition can Habronema cause?
summer sores
| ulcerative conjunctivitis
53
How do you dx stomach worms?
fecal floatation
| skin scraping of summer sores
54
How do you treat stomach worms?
ivermectin
| moxidectin
55
What is the roundworm (ascarids)?
Parascaris equorum
56
Where is Parascaris equorum most commonly found?
foals
| young horses
57
What can Parascaris equorum cause in foals/young horses?
impaction
telescoping of intestine
colic
58
T or F: Parascaris equorum interferes with digestion and absorption of nutrients, notably protein
True
59
What type of life cycle does Parascaris equorum have?
direct
60
T or F: Parascaris equorum larvae migrate through lungs where they can cause pneumonia
True
61
T or F: Parascaris equorum build up in large numbers in the anterior part of the small intestine
True
62
What is the infective stage of Pasaracis equorum?
2nd stage
63
Where is the Parascaris equorum located?
small intestine
64
What is the prepatent period of Parascaris equorum?
3 mo
65
What are the c/s of Parascaris equorum?
```
impaction colic (death)
pneumonia
pot belly
unthrifty appearance
poor hair coat
```
66
How do you dx Parascaris equorum?
c/s
fecal float
necropsy
67
How do you treat Parascaris equorum?
most common wormers
68
What are the tapeworms found in the horse?
Anoplocephala magna
A. perfoliata
Paranoplocephala mamillana
69
Where are tapeworms found?
mostly in cecum
| small intestine
70
What valve do tapeworms live at?
ileo-cecal valve
71
How do you treat tapeworms?
praziquantel
72
What is the name of the threadworm?
Strongyloides westeri
73
How long is the life cycle of a threadworm?
2 weeks
74
How are threadworms passed to foals?
in mother's milk
75
T or F: Threadworms cause heat foal diarrhea
False
76
T or F: Strongyloides is zoonotic and causes cutaneous larval migrans (but not the westeri)
True
77
How do you dx Strongyloides?
fecal exam for larvae
| fecal culture
78
How do you treat Strongyloides?
worm mare prior to foaling
| worm foal at 4wks of age
79
What is the Baermann apparatus used to detect?
lungworms
80
What are the common dewormers?
Avermectins (ivermectin (Eqvalan, Zimectin, Equimectrin), moxidectin(Quest))
Tetrahydropyrimidines (Pyrantel (Strongid, Rotation))
Benzimidazoles (Fenbendazole (Panacur, Safeguard))
Praziquantel
81
What parasites are located in the Liver?
Strongylus edentatus (larva)
82
What parasites are located in the Stomach?
Gastrophilus spp
Draschia megastoma
Habronema spp
83
What parasites are located in the Cecum/Colon?
Strongylus vulgaris
Strongylus edentatus
Strongylus equinus
small strongylus
84
What parasites are located in the Small Intestine?
Parascaris equorum
Strongyloides westeri
Paranoplocephala mammilana
85
What parasites are located in the rectum?
Oxyuris equi
86
What are the 3 classes of Phylum Arthropoda
Class Insecta
Class Arachnida
Class Pentastomida
87
What are the orders under Class Insecta?
```
Order Diptera (flies)
Order Phthiraptera (lice)
Order Siphonaptera (fleas)
Order Schizophora (bots)
```
88
What is in the Order Acarina?
ticks and mites
89
Where are the eggs of the botfly located on the horse?
hair of the forelegs, belly, flanks, shoulders
90
T or F: Only the female horse and deer flies bite
True
91
What is special about the saliva of the horse fly?
```
contains anti coagulant
transmits diseases (EIA, Anaplasmosis)
```
92
What does the Stable fly transmit?
EIA
| Habronema
93
What larvae cause Summer Sores?
Habronema muscae
| Habronema majus
94
What is Aberrant Parasitism?
when larvae is deposited in wounds
95
What is Culicoides hypersensitivity also known as?
queensland itch
sweet itch
summer itch
96
What season is Culicoides most seen in?
spring and summer
97
Where is "Sweet Itch" found?
tail
rump
back
withers
98
What do "No-See-Ums" transmit?
BTV (bluetounge virus)
EHD (epizootic hemorrhagic dz)
EIA
99
What diseases do Mosquitos transmit?
WEE
EEE
WNV
VEE
100
T or F: Screwworms are not reportable to USDA
False
101
T or F: Lice are Zoonotic
True
102
How are Mange Mites transmitted?
direct contact
| fomites
103
How are Mange Mites treated?
ivermectin
104
What do ticks transmit?
anaplasmosis
tularemia
tick paralysis
babesiosis
105
What equipment is needed to radiograph a horse?
```
radiograph machine
caliper
radiograph cassette holder
cassette/film
play-doh or putty
positioning blocks
processor to develop film
chemical sedation/restraint devices
PPE
```
106
Why would you pack the grooves of the sole with putty/play-doh?
to prevent artifacts created by air pockets of the hoof
| artifacts can sometimes mimic fracture lines and obscure true lesions
107
How far are you generally away from the patient when radiographing a horse?
30-40 inches
108
T or F: Removal of the shoe is recommended when taking a radiograph
True
109
Where is the beam centered when taking a lateral radiograph?
perpendicular to the middle carpal joint
110
Where is the beam centered when taking a flexed lateral radiograph?
centered at the middle carpal joint
111
Where is the beam centered when taking a dorsopalmar radiograph?
middle of carpal joint
| cassette is parallel to the palmar aspect of the limb
112
Where is the beam centered when taking a dorsolateral-palmarmedial oblique radiograph?
at middle carpal joint
113
What degree does the beam come from on a DLPMO radiograph?
60 degrees lateral off a straight dorsal palmar
114
What degree does the beam come from on a DMPLO radiograph?
60 degrees medial from a straight dorsal palmar
115
T or F: A patient doesn't need to be sedated for a CT or CAT scan
False
116
T or F: A patient must be injected with a radioisotope for a CT or CAT scan
True
117
T or F: MRI tend to be superior to CT for soft tissue imaging
True
118
What is MRI mainly used for?
dx equine lameness
119
What is Thermography primarily used for?
locate hot spots which may indicate inflammation near the body surface
120
T or F: Ultrasounds are superior to radiographs for visualizing soft tissues
True
121
What are some of the common uses of Ultrasound?
```
visualize kidneys and ultrasound guided biopsy
lungs for pneumonia dx and tx
GI for colics
liver ultrasound guided biopsy
assist with lameness dx
eyes
monitor mare's reproductive tract
genital tract in stallions
early detection of pregnancy
early detection of problem pregnancies
cardiovascular
image heart, lungs, kidneys, liver, spleen and intestines
```
122
What color does fluid appear on ultrasound?
black
123
What color does bone appear on ultrasound?
white
124
How do you prepare the patient for ultrasound?
clip the area
clean area
use coupling medium alcohol
commercial gel
125
What 2 basic varieties do endoscopes come in?
rigid
| flexible
126
What is an endoscope?
thin tube that contains a fiberoptic camera and a tool at the end allowing samples to be taken from various locations in the body
127
How many people does it typically take to operate an endoscope?
2-3
