Julia Miller's Equine + LA crash course +Udenburg Summary Charts Flashcards
She deserves a medal
Pruritic ectoparasites in horses
Chorioptes
Pediculosis
Fly bites
Less likely: Sarcoptes, Psoroptes
What is the typical age of onset of atopy in horses
THERE IS NONE. Can happen at any time
Causes of urticaria in horses
Food
Bug
Drug
Atopy
Causes of lichenification in horses
Culicoides hypersensitivity
Atopy
Onchocerciasis
Where do Culiocoides in the USA most like to bite on the body
Face, neck, ventrum, mane, tail
Where do lice cause pruritus in horses
Mane, tail, topline
Differentials for pruritus of the ventral midline in horses
Culicoides hypersensitivity
Atopy
Onchocerciases
Equine rump
Werneckiella equi
Sucking louse of horses
Haematopinus asini
Most common Staphylococcus folliculitis species in horses
S aureus
S hyicus hyicus
S delphini
Clinical signs of Malassezia dermatitis in horses
Udder, sheath dark brown debris
Tail rubbing
What do you need to add to your dermatophyte culture medium in horse samples
Niacin (T equinum)
Inositol + Thiamine (T verrucosum)
How to sample for Chorioptes
Feathers!
Acetate tape
Superficial skin scraping– CRUSTS
Most common culicoides r-allergens
Cul o 2
Cul o 3
Salivary proteins
Which cytokines are elevated in culicoides hypersensitivity
IL-4
IL-5
IL-13
IL-31
Th1 is unaffected or decreased. Th1 is PROTECTIVE against CH
Most common cause of allergic dermatitis in horses
Culicoides hypersensitivity
Breed predisposition for Culicoides hypersensitivity
Icelandic horses
Dutch Shetland Pony
Belgian Warmbloods
Queensland itch is ____
Culicoides hypersensitivity
Summer eczema is _____
Culicoides hypersensitivity
Sweet itch is _______
Culicoides hypersensitivity
Greasy heal is ______
Pastern folliculitis and furunculosis
(Usually Staphylococcus aureus, hyicus, delphini)
Phlegmon is _______
Cellulitis
(Coagulase positive Staphylococcus)
Heat Rash is ________
Staph F&F
Summer Scab is _______
Staph F&F
Sweating Eczema is _______
Staph F&F
Sweat Spots is ______
Staph F&F
Saddle Scab, Saddle Boil is ______
Staph F&F
Strangles is _______
Streptococcus equi equi
Wyoming Strangles, False Strangles is ________
Corynebacterium pseudotuberculosis
Pigeon Breast, Pigeon Fever is _____
Corynebacterium pseudotuberculosis
Rain Scald (dorsum), Rain Rot, Mud Fever (pastern, cannon) is _______
Dermatophilus congolensis
Dew poisoning is ______
Dermatophilosis of lightly pigmented areas
Dermatophilus crossover with photosensitization
Poll evil is _____
Actinomyces
Shigellosis is ______
Fatal septicemia of neonatal foals
Caused by Actinomyces equuli
Wooden tongue is _____
Pyogranulomatous Glossitis
Caused by Actinobacillus lignieresii
Malignant Edema causative agent
Clostridium septicum
Gas Gangrene causative agent
Clostridium perfringens
Equine Farcy, Glanders
Burkholderia mallei
Meliodiosis
Burkholderia pseudomallei
Champignon is ____
Spermatic Cord Botryomycosis
Caused by Stap aureus
Lumpy Jaw is _____
Actinomyces bovis
Mandibular Osteomyelitis
Black Leg is ______
Clostridium chauvoei
Bovine Farcy causative agent
Mycobacterium senegalense
Digital Dermatitis, Foot Warts, Heel Warts, Strawberry Heel Warts is ________
Papillomatous Digital Dermatitis
Caused by Treponema
Interdigital Dermatitis, NON-papillomatous interdigital dermatitis in farm animals is ______
Dichelobacter nodosus
Goat Pox is _____
Impetigo
Staph aureus, hyicus, chromogenes
Big Head is ______
Goats, Sheep
Clostridium novyi
Clostridium oedematiens
Eye Scab, Peri-Orbital Eczema in sheep is _______
Staph aureus, xylosus
Lumpy Wool, Strawberry Foot rot, Yellow Wool in Suffolk/Romney Sheep is _______
Dermatophilus congolensis
Fine wooled sheep
Leather Lips, Cruels is ____
Actinobacillus lignieresii in sheep
Greasy Pig Disease
Exudative Epidermitis
Staph hyicus
Diamond Skin Disease is
Subacute Erysipelas
Erysipelothrix rhusiopathiae
MR Staph aureus
CA-MRSA-5/ USA500
CC8
SCCmec IV
T or F: Streptococcus equisimilis is zoonotic
True
Vector for Corynebacterium pseudotuberculosis
Haematobia irritans (horn)
Stomoxys calcitrans (stable)
Musca domestica (horse)
Horses predisposed to botryomycosis with Coagulase + Staph, Pseudomonas aeruginosa, Actinobacillus equuli
PPID
Bacteria that can cause acute thrombosis of digital arteries
Salmonella infantum
Opportunistic nodular wound contamination Mycobacterium in horses
Mycobacterium smegmatis
Widespread exfoliative granulomatous dermatitis of the udder in horses
Mycobacterium avium avium
How do horses develop anaerobic infections (Bacteroides, Fusobacterium, Clostridium)
Skin surface of MM commensals: 2’ to trauma, surgery
Cellulitis, nodules, draining tracts
Debridement + Penicillin
Treatment for Staphylococcus F&F in horses
(common in tack-bearing regions)
TMS
Poor susceptibility to penicillin, tetracycline
Most common culicoides species in the USA
Culicoides sonorensis
Also Culicoides insignis
Where do culicoides like to lay their eggs
Near water, vegetation, slow running streams
When do culicoides feed
Dusk and dawn
STABLE YOUR HORSE OVERNIGHT
Vector for Onchocerca
Culicoides
Which biting fly is very seasonal? Only out during spring-fall
Culicoides
T or F: IDST and serum testing for Culicoides hypersensitivity has a low sensitivity and specificity
True. Likely because we use whole body extracts
May be better in the future with r-allergens
Best treatment for Culicoides
Avoid gnat population
Fans
Remove water from area, or move horse away from standing water
Inside at dusk/dawn
Topical repellent treatments for culicoides
Permethrin >1%
Neem oil
Blocking which 2 cytokines shows promise in managing culicoides hypersensitivity
IL-5 (vaccine, eosinophils)
IL-31 (pruritus)
1 cause of PERSISTENT urticaria in horses
New hay!!
Also new pasture, new grains, new supplements
1 cause of TRANSIENT urticaria in horses
Biting insects
Tabanids (horse fly)
Wasps, Bees
Which drugs have been implicated in urticaria in horses
SMZ
Prascend
Regumate
Joint injections, Adequan
Vaccines
Supplements
Shampoos, fly sprays, bedding
Best treatment for urticaria in horses
Glucocorticoids: short, tapering protocol
+/- antihistamines
Do not use antihistamines as a monotherapy
Horse breed predisposed to atopy
Thoroughbred
Quarterhorse
Arabians
When does JMiller read her horse IDSTs?
15 mins, 30 mins
4-6 hr
24 hr
Response to ASIT in horses
70-80% satisfaction
Results in 3 months possible
Does ASIT work for equine asthma
Not proven
JMiller says it helps in 50% of her cases, but for the sake of the exam, we have no data to say it helps
Dose of cetirizine for a horse
0.2-0.4 mg/kg q12h
Dose of hydroxyzine in a horse
1-2 mg/kg q8-12h
Does Apoquel work for horse Atopy?
It can but its off label
DO NOT USE in insured horses
Safety unknown, esp long term
May help with pruritus, less helpful for hives
Scratches, mud fever, grease heel, mallanders, grapes is ______
Pastern dermatitis
Cutaneous reaction pattern
What should you consider in a horse with pastern dermatitis
Predisposing factors
Primary factors
Perpetuating factors
What are the predisposing factors for horse pastern dermatitis
Environmental
Genetic
Iatrogenic
What are the primary factors for horse pastern dermatitis
Physical irritants
Immune mediated
Parasitic
Neoplastic
What are the perpetuating factors for horse pastern dermatitis
Bacteria
Fungi
Environmental
Most common cause of pastern dermatitis in horses
Wound, trauma, maceration
“Clean and dry is worth a try”
Diagnosis?
Habronema
Vector?
Stomoxys calcitrans (stable fly)
Musca domestica (house fly)
Habronema
Diagnosis?
Photosensitization
Dilution of lime sulfur dip
Dilute to 3-4%
Do NOT rinse off
Which equine bacteria ARE susceptible to penicillins
Streptococcus, Dermatophilosis
DONT USE IN STAPH
Absorption of doxycycline in horses?
Poorly bioavailable
Minocycline is better
Oral treatments for Dermatophilosis
TMS
PPG
Topicals are great though! LSD, chlorhex
Diagnosis? Horse CRUST bx
Dermatophilosis
Railroad track
Which plants can cause PRIMARY photosensitization
St Johns Wort
Clover
Bishops Weed
Which drugs can cause PRIMARY photosensitization
Sulfonamides
Tetracyclines
Topical antimicrobials
What agent is implicated in SECONDARY photosensitization
Phylloerythrin
Hepatic dysfunction, so phylloerythrin is not excreted, ends up in skin –> phototoxic
Which plants cause SECONDARY photosensitization
Ragwort
Heliotrope
Rattlebox
Labwork to run in equine photosensitization cases
GGT, SDH (liver!)
Treatments for photosensitization
UV avoidance
Topical GCs
Systemic antiinflammatories
Tx 2’ infection
Triggers for cutaneous vasculitis in horses
Drug, illness, vaccine, etc
Triggers for pastern leukocytoclastic vasculitis
Photo-aggravated
Staph, dermatophilosis, trauma
NOT hepatic
Location of pastern leukocytoclastic vasculitis
Non-pigmented distal extremities
Immune-complex disease
-Superficial vascular plexus
When I say pastern leukocytoclastic vasculitis, you say _____
Immune complex disease of the superficial vascular plexus!
Treatment for equine cutaneous vasculitis
Eliminate triggering antigen
Glucocorticoids
Pentoxifylline (10-25mg/kg BID)
Azathioprine
+/- minocycline
Prognosis of cutaneous vasculitis in horses
Poor
Does Chorioptes burrow in the skin?
No
Non-burrowing mite
Feeds on cellular debris, hides in long hair
How long can chorioptes live OFF the host
Approx 3 months
Treatment for chorioptes
Clip feathers!!
LSD
Fipronil
T or F: there are asymptomatic carriers of chorioptes
True
Draft horse. Diagnosis?
Chronic progressive lymphedema
What causes chronic progressive lymphedema
Unknown if genetic of inflammatory dz PRIMARY
- Dysfunction of the lymphatic system –> lympedema
- Lower elastin concentration in skin, anti-elastin antibodies
- Fibrosis
- Inflammation
Which gene has been evaluated for chronic progressive lymphedema, and is NOT associated with CPL in horses
FOXC2
3 species causing Summer Sores
1) Habronema muscae
2) Habronema majus
3) Draschia megastoma
Pathogenesis of Habronemiasis
Horse ingests larvae
Adults live in stomach lining –> poop out larve
Flies eat larvae from feces
Flies = intermediate host
Flies deposit larvae in wounds, nostrils, mouth
Cause LOCAL HYPERSENSITIVITY REACTION
Clinical signs of habronemiasis
Non healing, exuberant, granulomatous lesions
3rd eyelid, mouth, coronary band, penis
Horse. Diagnosis?
Habronemiasis
Granulomatous, foci of eosinophils with a nematode in the center
Treatment for Habronemiasis
Topical GCs
Wound management
Ivermectin, moxidectin PO
Surgical debulking
Fly control
Tx 2’ infections
Risk factors for pediculosis
Winter
Overcrowding
Poor health, nutrition
Young animals
Body distribution of pediculosis
Mane + tail > body
Pruritus
Differences in treatment between Chewing and Sucking lice
Chewing: Topicals only
Sucking: Systemics + topicals
LSD, permethrin pour on, eprinomectin pour on (cows, goat)
Ivermectin
River Blindness is _____
Onchocerciasis
Ocular signs: Depigmentation of conjunctiva, keratitis, uveitis
Where do Onchocerca cervicalis adults live
Nuchal ligament
Intermediate host of Onchocerca cervicalis
Culicoides
Location of lesions correlate to where gnats feed
What causes the skin lesions in onchocerciasis
Microfilaria in the dermis
T or F: Onchocerciasis is pruritic
True
Treatment for onchocerciasis
Ivermectin = microfilaricidal
BUT no treatment for adults!
(think heartworm)
3 risk factors for sarcoids
1) Exposure to BPV (but also in healthy skin!)
2) Local cutaneous trauma (allows viral activation)
3) Genetic predilection (certain MHC profiles, QH, Ap, Arabian, TB, WB)
What TYPE of sarcoid is this
Occult
(Flat)
What TYPE of sarcoid is this
Verrucous (Irregular, wart-like)
What TYPE of sarcoid is this
Nodular
Type A = SQ with normal overlying skin
Type B = Dermal with ABNORMAL overlying skin
What TYPE of sarcoid is this
Fibroblastic
Type 1: Pedunculated
Type 2: Sessile, broad-based
What TYPE of sarcoid is this
Malevolent, Malignant
Locally invasive, aggressive
Hx repeat trauma
Likely to recur after sx
What TYPE of sarcoid is this
Mixed
No predominant type
Likely transient, progressive state
Gold standard to diagnose equine sarcoids
Biopsy
PCR NOT helpful (BPV on normal skin too)
FNA is inconclusive
Ingredients in XXTERRA (sarcoid tx)
Blood root powder, alkaloid (cytotoxic)
ZnCl (proinflammatory)
Antigenic to host
Effective but inflammatory
Imiquimod cytokines upregulated
Th1: IL-2, IL-12, IFNa, IFNg
TNFa, IL-1, IL-6, IL-8
MOA 5-fluorouracil
Inhibits viral DNA replication, blocks thymidylate synthetase
Intratumoral injection of sarcoids
What adjustment can you make to cisplatin administration that may make it more effective for equine sarcoids
Electrochemotherapy (also sx)
Electrical field pulses increase cell membrane permeability– more cisplatin can get inside
AE of cryotherapy in horses
Leukotrichia
Which sarcoid location is responsive to intralesional BCG immunotherapy
Periocular sarcoids
Nodular, fibroblastic only
Risk of anaphylaxis
Do non-grey horses have a higher or lower risk of malignant melanomas?
Higher chance of malignancy in non-grey horses
T or F: 80% of 12+ yr old grey horses have melanomas
True. 95% are benign at time of diagnosis, but many become malignant with time
Most common location of dermal melanoma in grey horses
Tail, perineum
Also lips, prepuce, eyelids, parotid SG
Age, body location, prognosis of melanocytoma in horses
YOUNG horses (< 8 yr)
Legs, neck, trunk, face
Benign
NOT perineum, penile, eyelid– that’s dermal melanomas
Treatment of choice for dermal melanoma
Surgical excision
+/- laser, cryotherapy
T or F: cisplatin injection is an option for non-resectable melanomas
True
Can also use carboplatin; debulk if >3cm
Target of Oncept melanoma vaccine
DNA vaccine against Tyrosinase
Melanomas overexpress tyrosinase
Elicits humoral and cell-mediated immunity
Most common tumor affecting the equine eye
SCC
Most common tumor affecting male genitalia
SCC
Risk factors for SCC in horses
Older age
Non-pigmented skin
Excessive sunlight
Draft horses
Pre-cancerous lesions that can convert to SCC in horses
Actinic keratosis
Carcinoma in situ
Chronic keratosis
Chronic skin inflammation (smegma, injury) and UV light are important!
Which virus is commonly found in ocular and genital SCC in horses
EcPV-2
Necessary but not sufficient to induce SCC
Treatment for SCC in hroses
Wide surgical excision
Enucleation or phallectomy
Treatment for equine viral papillomatosis
(young horse, lips/nose)
Leave alone!
Spontaneously regress in 2-3mo
Treatment for equine genital papillomas
(older horse)
Surgical excision
Transformation to SCC
Vector for equine aural plaques
Black flies
Test you can do to evaluate for equine anhidrosis
Intradermal injections of epinephrine, terbutaline
Stimulate sweat glands
Origin of humoral control of equine sweating
Adrenergic agonists secreted from adrenal medulla into circulation
Nervous control of equine sweating
Autonomic adrenergic nerves
Trigger for equine anhidrosis
Continued adrenaline-driven hyperactivity (from climate stress)
Risk factors for Bovine Dermatophytosis
Weak immune system (calves, heifers)
Poor nutrition, overcrowding
Winter
Treatment for Bovine Dermatophytosis
Spontaneous remission is common
Remove thick crusts
SUNSHINE
Topical tx: Hypochlorite, LSD, betadine, chlorhex
Causative agent of herpes mammillitis in cows
BHV-2
Direct contact, insect vectors
Cow chewing louse
Damalina bovis
Cow sucking louse
Solenopotes capillatus
Cow sucking louse
Linognathus vituli
Cow sucking louse
Haematopinus eurysternus
Which goat parasite can cause pruritus due to nerve pain
Parelaphostrongylus tenius
Neuro exam, CSF
Tx: Fenbendazole
Very common cause of pruritus in goats
Chorioptes bovis
Also pediculosis
Cause of pruritus in this goat
Pediculosis
R/o Linognathus stenopsis, Linognathus africanus, Damalinia caprae
Goat
Linognathus stenopsis, Linognathus africanus
Goat
Damalina caprae
Treatment for contagous pustular dermatitis, Orf in goats
Self resolves
Treat 2’ infections
Vaccine?
Parapox virus
Itchy mite in pigs
Sarcoptes scabiei var suis
Treatment of dry, flaky pig skin
Humidifier
Topical moisturizer
Treatment sarcoptes scabiei var suis in pigs
Ivermectin PO/SC/IM
Idiopathic swine hyperkeratosis is most common in type of husbandry situation
House pigs
Limited access to roll/scratch outside
Hyperkeratotic skin on dorsum
Treatment = moisturizing agents, or ignore it
What organism is super common in pig facial folds and ears without causing disease
Malassezia
Treat only if clinical
Which pigs are predisposed to SCC
Pink pigs kept outside
Try sunscreen
If you see a camelid on the boards exam, your answer should be _____
Chorioptes bovis
Most common cause of pruritus in alpacas
Chorioptes bovis
Body locations affected by Chorioptes bovis
Ventrum, perineum, feet, thighs
Bacteria that can cause pododermatitis in camelids
Staphylococcus
Trueperella
Fusobacterium
Munge is ______
Idiopathic nasal hyperkeratotic dermatosis in camelids
Treatment of Idiopathic nasal hyperkeratotic dermatosis in camelids
Topical GC + antimicrobials
Vector for Warbles
Hypoderma bovis
Hypoderma lineatum
Vector for myiasis
Lucilia
Calliphora
Phormia
= Blow flies
Vector for Stephanofilariasis
Haematobia irritans (horn fly)
How to avoid Haematobia irritans
Remove COW manure
Vector for Corynebacterium pseudotuberculosis
Horn flies
Haematobia irritans
Vector for EHV aural Plaques
Simulium (Black flies)
Stomoxys calcitrans (Stable flies)
Where do black flies like to lay their eggs
Running water
Vector for Habronema
Majus = stable fly
Muscae = House fly
T or F: EM can look like hives in horses
True!
If hives don’t go away, biopsy to r/o EM
Equine breed overrepresented for pemphigus foliaceus
Appaloosas, usually young
Young horses have better response w/no relapse
Which plant is linked to Systemic granulomatous disease (sarcoidosis) in horses, cattle
Hairy Vetch
Abnormal host response to antigens
Thoroughbreds predisposed