Unit 4 - Equine Skin and FAD

Question 1

Corynebacterium pseudotuberculosis var. equi is a natural inhabitant of what?

Answer 1

the soil

Question 2

How is Corynebacterium pseudotuberculosis var. equi transmitted?

Answer 2

Via any break in the skin or biting insects

Question 3

What are the three forms of disease/clinical signs caused by Corynebacterium pseudotuberculosis var. equi?

Answer 3

External abscesses (Pigeon fever)
Internal abscesses
Ulcerative lymphangitis

Question 4

What age group of horses are predisposed to pigeon fever?

Answer 4

young

Question 5

What lesions are associated with pigeon fever?

Answer 5

Large pectoral abscesses and on the ventral abdomen

Question 6

Where do internal abscesses due to Corynebacterium pseudotuberculosis var. equi typically localize?

Answer 6

On the liver, lung, spleen, and kidney

Question 7

Ulcerative lymphangitis is characterized by what?

Answer 7

Severe cellulitis of one or more limbs

Question 8

How is Corynebacterium pseudotuberculosis var. equi diagnosed?

Answer 8

Bacterial culture of lesions, peritoneal fluid, or draining tracts
Evidence of chronic infection on CBC
Synergistic hemolysis inhibition

Question 9

How are the external abscesses caused by Corynebacterium pseudotuberculosis var. equi treated?

Answer 9

Surgical drainage ofmature abscesses
Many abscesses will rupture and heal on their own
Antibiotics only in complicated cases

Question 10

T/F: There is a low chance of recovery associated with pigeon fever.

Answer 10

False - it is high

Question 11

How are internal abscesses and ulcerative lymphangitis caused by Corynebacterium pseudotuberculosis var. equi treated?

Answer 11

Long term (minimum 4-6 weeks) of antibiotic therapy

Question 12

How is Corynebacterium pseudotuberculosis var. equi prevented and controlled?

Answer 12

Isolate infected animals
Contain abscess drainage
Fly control
Vaccination

Question 13

What is the etiology of sporothricosis?

Answer 13

Sporothrix schenckii

Question 14

What does sporothricosis present similarily to?

Answer 14

ulcerative lymphangitis

Question 15

Where does Sporothrix schenckii grow?

Answer 15

In organic material - silvers and thorns

Question 16

How is sporothricosis introduced?

Answer 16

Via trauma

Question 17

What clinical signs are associated with sporothricosis?

Answer 17

Multiple abscesses along lymphatic vessels

Typically affects a single limb

Question 18

How is Sporothricosis diagnosed?

Answer 18

Cytology
Culture
Lack of response to antibiotic therapy

Question 19

What will you see on cytology in patients with sporothricosis?

Answer 19

Cigar bodies - elongated yeast cells

Question 20

How is sporothricosis treated?

Answer 20

Sodium iodide with Ketoconazole (or similar drugs) OR amphoteracin B

Question 21

What are the infectious causes of folliculitis/dermatitis?

Answer 21

Dermatophilosis
Dermatophytosis
Bacterial pyoderma
Parasitic - chorioptic and psoroptic mange

Question 22

What are the most common etiologic agents of dermatophytosis?

Answer 22

Trichophyton equinum
T. mentagrophytes
Microsporum gypseum

Question 23

What are the common etiologic agents of dermatophytosis if there is interaction with other infected animals?

Answer 23

T. verrucosum

M. canis

Question 24

How does dermatophytosis colonize?

Answer 24

It requires some abrasion to skin to allow entry

Question 25

What clinical signs are associated with dermatophytosis?

Answer 25

Regions of alopecia, frequently round, erythemic, crusted margins Located on the head, neck, forelimbs, under saddle/girth

Question 26

How is dermatophytosis diagnosed?

Answer 26

Culture is the best bet

Question 27

How is dermatophytosis treated?

Answer 27

``` Most cases are self-limiting Can treat topically with antifungals or lime sulfur +/- systemic therapy Separate from herd Disinfect equipment ```

Question 28

What is the etiologic agent of dermatophilosis?

Answer 28

Dermatophilus congolensis

Question 29

How does Dermatophilus congolensis enter the body?

Answer 29

Skin abrasion and moisture

Question 30

T/F: The crusts from dermatophilus infected individuals are contagious

Answer 30

True

Question 31

What is another name for dermatophilosis?

Answer 31

Rain rot

Question 32

What lesions are associated with dermatophilosis?

Answer 32

Papules that progress to thick crusts with an erosive underside (paint brush lesions)

Question 33

How is dermatophilosis diagnosed?

Answer 33

Direct examination of crusts | Giemsa stain

Question 34

How is dermatophilosis treated?

Answer 34

Dry environment Crust removal Topical chlorhexidine +/- systemic therapy with abx

Question 35

What is the etiologic agent of vesicualr stomatitis?

Answer 35

Vesicular stomatitis virus

Question 36

Where is vesicular stomatitis endemic?

Answer 36

In North, Central, and South America

Question 37

During what time of year is vesicular stomatitis common?

Answer 37

Spring to summer months - waterways

Question 38

How is vesicular stomatitis transmitted?

Answer 38

Via biting insects and direct contact once on property

Question 39

T/F: Vesicular stomatitis is zoonotic..

Answer 39

True

Question 40

What clinical signs are associated with vesicular stomatitis?

Answer 40

Excessive salivation with vesicles on the inner surface of the lips, gums, and tongue - occasional crusting on muzzle, lips, nostrils, ears, coronary band, sheath, ventral abdomen

Question 41

How is vesicular stomatitis diagnosed?

Answer 41

Report any suspicious lesions to the state vet PCR from lesions Serology

Question 42

How is vesicular stomatitis treated?

Answer 42

supportive care

Question 43

How is vesicular stomatitis prevented and controlled?

Answer 43

Quarantine of any identified premises Isolate any new horses for 21 days Insect control programs Individual feeders

Question 44

What transmits African horse sickness?

Answer 44

Biting midges

Question 45

What serves as reservoirs for African horse sickness?

Answer 45

Donkeys, mules, zebras, elephants, camels, and dogs

Question 46

what complicates the prevention of African horse sickness?

Answer 46

The antigenic variants

Question 47

Where is African horse sickness endemic?

Answer 47

Sub-Saharan Africa

Question 48

What cell does African horse sickness attack and what does that result in?

Answer 48

Vascular endothelium resulting in edema

Question 49

What are the forms of African horse sickness?

Answer 49

Pulmonary, cardiac, mixed, mild

Question 50

What clinical signs are associated with the pulmonary form of African horse sickness?

Answer 50

Severe pulmonary edema, frothing at the nares, high fever, and 95% case fatality rate

Question 51

What clinical signs are associated with the cardiac form of African horse sickness?

Answer 51

Pronounced edema of the head and neck, hydropericardium, and high case fatality rate

Question 52

What clinical signs are associated with the mild form of African horse sickness?

Answer 52

Fever only

Question 53

How is African horse sickness diagnosed?

Answer 53

Clinical signs Virus isolation PCR if available Serology

Question 54

Is African horse sickness treatable?

Answer 54

Not really - supportive care is the best you can do because it is highly fatal

Question 55

How is African Horse sickness prevented and controlled?

Answer 55

Strict importation rules Control biting midges Screening/netting at night Vaccination

Question 56

What is the reservoir of Hendra virus?

Answer 56

fruit bat

Question 57

How is Hendra virus transmitted between horses?

Answer 57

Direct contact only with respiratory secretions

Question 58

T/F: Hendra virus is highly fatal and zoonotic

Answer 58

True

Question 59

What clinical signs are associated with Hendra virus?

Answer 59

Fever, respiratory distress, and death Severe bilateral pulmonary edema Potential for neurologic signs

Question 60

Where does Hendra virus replicate? How does it spread?

Answer 60

Replicates in respiratory epithelium first, then spreads hematogenously to other organs

Question 61

How is Hendra virus diagnosed?

Answer 61

RNA virus - RT-PCR | Serology

Question 62

How is Hendra virus treated?

Answer 62

No treatment - euthanized to protect human health

Question 63

What is the etiologic agent of glanders?

Answer 63

Burkholderia mallei

Question 64

T/F: Burkolderia mallei lives in the soil and is zoonotic.

Answer 64

False - it is zoonotic but it is an obligate parasite of equidae and dies out in the environment fairly quickly

Question 65

How is Burkholderia mallei discharged from a horse?

Answer 65

Draining nodules and nasal mucosa

Question 66

How is glanders transmitted?

Answer 66

Feed, water, and direct contact

Question 67

What is a key to glanders transmission?

Answer 67

Recovered carriers

Question 68

What equidae species tend to develop chronic glanders? acute disease?

Answer 68

Chronic - horses | Acute - donkeys and mules

Question 69

What are the forms of glanders?

Answer 69

Respiratory and cutaneous

Question 70

What are the respiratory clinical signs of glanders?

Answer 70

Pneumonia Small nodules on the nasal and pharyngeal mucosa that ulcerate and drain Ulcers will heal and scars form (stellate scars)

Question 71

What are the cutaneous clinical signs of glanders?

Answer 71

Nodules on skin, subcutaneous tissues, and lymph nodes | Lymphangitis

Question 72

What form of glanders do humans get?

Answer 72

Primarily cutaneous but can get respiratory

Question 73

How is glanders diagnosed in acute cases?

Answer 73

Culture or PCR of lesions | Postmortem lesions and culture

Question 74

How are carriers of glanders detected?

Answer 74

Serology - CF (official test for import), ELISA, AGID | Mallein intradermal skin test

Question 75

How is glanders treated?

Answer 75

It is not recommended - don't want carriers

Question 76

How is glanders prevented and controlled?

Answer 76

Test and slaughter is preferred - no vaccination

Question 77

What is the etiologic agent of dourine?

Answer 77

Trypanosoma eqiperdum

Question 78

T/F: Dourine is common in all hooved species.

Answer 78

False - only in equidae

Question 79

How is dourine transmitted?

Answer 79

venereally

Question 80

Where is dourine found?

Answer 80

Central and S. America, N. Africa, and the Middle East

Question 81

When is the onset of dourine?

Answer 81

Up to 20 weeks

Question 82

What acute signs are associated with dourine?

Answer 82

Initial low-grade fever and urethral or vaginal discharge Edema, swelling, and ulceration of external genitalia Occasional abortion

Question 83

What chronic signs are associated with dourine?

Answer 83

Peculiar raised plaques in skin of the flank that disappear and are replaced by plaques in other areas (pathognomonic) CNS signs - incoordination, ataxia, paralysis Loss of condition and progressive weakness

Question 84

How is dourine diagnosed?

Answer 84

Clinical signs Serologic testing Real-time PCR

Question 85

How is dourine treated?

Answer 85

Use of trypanosomal drugs is possible... but not practical

Question 86

How is dourine prevented and controlled?

Answer 86

Slaughter of all CF positive carrier animals