Equine Skin Disease

Question 1

What species of lice affect horses?

Answer 1

Damalinia equi (biting)
Haematopinus asini (sucking)

Question 2

What time of year do lice infestations of horses occur?

Answer 2

Winter

Question 3

How are lice infestations treated in horses?

Answer 3

Cypermethrin spray/sponge on whole body
Permthrin and citronellol sponge
Piperonyl butoxide shampoo
Suitable insecticides for grooming kit, blankets and stable area

Question 4

Why should pyrethrins be dispoesd of very carefully?

Answer 4

They are extremely toxic to aquatic life

Question 5

What is the most common mange in horses?

Answer 5

Chorioptic

Question 6

What species causes mange in horses?

Answer 6

Chorioptes bovis

Question 7

where do chorioptic mange lesions occur in the horse?

Answer 7

Distal limb of horses with feathered heels

Question 8

What is the most likely cause of reinfestation of chorioptic manage in horses?

Answer 8

From the env

Question 9

Are there any licensed products for treating chorioptic mange in horses?

Answer 9

No

Question 10

What can be used to treat chorioptic mange in horses?

Answer 10

All off license:

• Oral ivermectin (NOT SPRAY)
• Selenium sulphide shampoo
• Fipronil spray
• Flumethrin (sheep dip)

Question 11

Which durg is absolutely contraindicated for treating demodex in equidae and why?

Answer 11

Amitraz - alters gut motility leading to colic

Question 12

What is the proper term for sweet itch?

Answer 12

Culicoides hypersensitivity

Recurrent seasonal pruritis

Question 13

What is Culicoides?

Answer 13

Midge

Question 14

Why is sweet itch a significant disease?

Answer 14

Welfare

Management problems

Question 15

What are the clinical signs of sweet itch?

Answer 15

Pruritus and lesions along the dorsal midline, mane and tail and sometimes ventrally

Question 16

What treatment is licensed for sweet itch?

Answer 16

Benzyl benzoate solution

Question 17

Why are permethrins a poor choice for treating sweet itch?

Answer 17

Need frequent application - expensive

Question 18

What is the most effective method of preventing sweet itch? How can this be achieved?

Answer 18

Prevention of midge feeding

• Stable horses at dawn and dusk
• Ceiling fans
• Insecticidal strips
• Graze on well drained land away from standing water
• Fly repellant ear tages tied to head collar
• Rugs with hoods

Question 19

Which mites affect horses?

Answer 19

Red mite

Harvest mite

Question 20

What are infectious causes of pastern dermatitis syndrome?

Answer 20

Bacteria
Fungi
Parasites

Question 21

What are non-infectious causes of pastern dermatitis syndrome?

Answer 21

Physical
Neoplasia
Immune-mediated
Miscellaneous - greasy heel syndrome

Question 22

What are the clinical signs of pastern dermatitis in horses?

Answer 22

Back of pastern
>1 leg
Papules => large areas of ulceration and suppuration

Question 23

How is pastern dermatitis diagnosed in horses?

Answer 23

History and clinical signs
Biopsy
Bacterial and fungal culture

Question 24

How is pastern dermatitis treated?

Answer 24

Remove crust and clip hair thoroughly
Wash with antiseptic surgical scrub
Antifungals, anti-inflammatories and AB
Corticosteroids

Question 25

What are the characteristics of where greasy heel lesions are found?

Answer 25

Posterior of hind pastern White-socked May extend to fetlock and front of leg May affect more than one leg

Question 26

What breeds is greasy heel more common in?

Answer 26

Feathered breeds | Draught horses

Question 27

What are the clinical signs of greasy heel?

Answer 27

``` Erythema Oozing, crusting Alopecia Vasculitis Erosion and ulceration Thickening of skin Pruritus Granulation tissue Pain, lameness ```

Question 28

How is greasy heel treated in horses?

Answer 28

``` Eliminate all possible causes Topical antiseptic washes Removal of all hair and necrotic tissue Keep as dry as possible NSAIDs, AB ```

Question 29

Where on the body of equids are Chorioptes spp and Psoroptes spp found?

Answer 29

c - Limbs and tail | p - Head and ears

Question 30

What species of pinworm affects horses?

Answer 30

Oxyuris equi

Question 31

What is the most common skin allergy in horses?

Answer 31

Sweet itch

Question 32

What are the most common bacterial skin infections of horses?

Answer 32

``` Staph Dermatophilus congolensis (mud fever/rainscald) ```

Question 33

What is the appearance of Dermatophilus congolensis microscopically?

Answer 33

Train-track bacteria

Question 34

What type of virus causes aural plaques in horses?

Answer 34

Papillomavirus

Question 35

What immune-mediated disease affect horses in dermatology?

Answer 35

``` Pemphigus foliaceus Erythema multiforme ADRs Vasculitis Alopecia areata ```

Question 36

What are the clinical signs of Cushing's/PPID in horses?

Answer 36

``` Old age PUPD Lethargy Laminitis Thick, dark excessive hair growth ```