RUM 510 SKIN
Orf 👫 
Ax
Parapoxvirus
Resistant, can persist on environment for ~1y on equipment
Sx
Young SS
CS
Papules -> pustules -> rupture and form scabs
Lesions in the hoof -> lameness
Control
OBP vaccine
Autogenous vaccine via scarification, check for a pustule in 3-4d
Dermatophytosis 👫
Ax
⭐Trichophyton verrucosum
Microsporum
Epidermophyton
Sx
Calves, esp in poor BCS
Predisposing causes
Nutritional def, esp Vit A
Reduced immunological competace
Immunologically naive herd
Hot, wet conditions (Summer)
Intensive Housing
CS (IP 1-3w)
Non pruritic, keratinised, circular periocular lesions
May become generalised
Older female cattle: chest +limbs
Bulls: dewlap, ontermaxillary skin
Dx
Visualization: Skin Scrape-Look for characteristic hyphae. Can dissolve hair with KOH - easier to visualize
Culture - removed a pluck of hair close to the lesion margin and send for culture. takes 4w though
Tx
Self limiting in 1-4m
Dog + Cat Tx like Griseofulvin, lime sulphur = expensive. Reserved for show animals
Captan powder 1:200 cost effective for ruminants. Mix with water and apply daily
Dermatophylosis / Rain Scald 👫
Ax
Dermatophilus congolensis
Gram+, non acid fast, fac anaerobe, fungal like
Epidemiology
Spread by direct contact / fomites
Predisposing factors
Hot, wet environment (Summer) -> sporolation
Ectoparasites - damage skin
Capnophillic: forms zoospores in CO2 environments
Damaged skin -> increased CO2 -> germination of zoospores -> spread of hyphae into epidermis and inflammation
Tx
Most heal spontaneously in 2-3w
Pathogensis
Stage 1
Stage 2
Stage 3
Hair matted together, paintbrush lesions
Lesions coalesce -> scabs / crusts
Accumulation of cutaneous keratinised material -> wart like lesions 0.5-2cm
DD: Papillomas, but dermatophilosis lesions peel off easily
CS
Confluent crusting
Poor doers
Wool / hide damage
Secondary blow fly strike
Secondary bacterial infection
Economic
Due to exudate on surface
Dx
Bacterial culture - DEFINATIVE
Indirect fluorescent AB testing
Histopath / Biopsy
Suspicion- smear underside of scab on slide, stain, look for railroad
First line: Long acting Tetracyclines / Penicillin, repeat x3 every 3 days
Lo
Topical: F10 germicidal
Control
Prevent constant wetting
Fix fences so animals don't injure skin
Besnoitia / Elephant skin Disease
Ax
Cattle: Besnoitia besnoiti
Goats: B. caprae
Epidemiology
Uncertainty...
Cats (DH?) shed mature oocytes in feed or water
Contaminated needles
Mechanically biting insects
Pathogenesis
Ingestion of oocytes -> Tacchyzoites infect endothelial cells -> vascular permeability and oedema
CS (IP 2w -> 2m)
Economic Losses
Sterility in bulls
Reduced milk production
Skin lesions -> poor hides
Mortality (but <10%)
- Anasarca Stage (mostly unnoticed)
Pyrexia, inappetence, weight loss, recumbency
Generalized oedema, swelling of the face and neck folds
Ocular + nasal discharge
Photophobia + hyperaemia of skin
Gen lymphadenopathy
Swollen, sensitive testes
- Scleroderma / Elephant skin disease stage (3w after CS)
Oozing serosanguinous exudate -> maggot infestation
Thick, cracked skin
Secondary bacterial infection
Myasis
Movement painful
Loss of hair + epidermis
+- myositis, keratitis, periostitis, pneumonia, orchitis, epididymitis, perineuritis (due to widespread vasculitis)
Cyst on scleral conjunctiva and nasal mucosa 6-7w after pyrexia
Lifelong carriers
Dx
Clinical Signs
Histopath of cysts
PCR
Tx (recovery is poor))
Oxytet- MAY BE helpful of given early)
Control of secondary conditions- wound dressing, F10 ointment, nutritious food)
Consider early slaughter, these animals don't gain weight well
Bovine Parafilariosis / False bruising
Ax
Parafilaria bovicola
Females 50-65mm
Found anywhere you find Musca flies
Transmission through feeding of Musca autumnalis, lusoria, xanthomeles on wounds / ocular secretions
Pathogenesis (PPP = 7-10m)
Parafilaria worms lay eggs in bleeding spot
Musca flies ingest eggs when taking in a blood meal
Larval development in fly (L1 -> L3) in 10-12d
Fly feeds on lacimal secretions of another animal - deposits eggs
Eggs devlope into adult under the skin in 5-7m.
CS
Economic Losses
Green, yellow lesions resembling bruising, may extend into muscle
Severe: caracass condemned
Carcass trimming and downgrading
Considering long PPP, feedlot animals show these signs around slaughter
Focal cutaneous bleeding spots
Early spring + summer
DD
Trauma. But will affect many animals and seen in summer specifically
Dx
Female lives in a nodule at the skin surface -> pierces through to lay eggs
Presence of parasite eggs + microfilaria in blood
Biopsy of nodule for histopath
Centrifuge dry blood - will see eggs in the sediment
Abattoir: "bruising," metallic smell
Tx
Ivermectin / MLs
Only kills adults, microfilaria may cause resurgence of CS
Treat between 70-120d before slaughter to allow time for larvae to resolve and prevent resurgance
Myasis / Fly Strike
Oestrus ovis / Nasal Bot
Chrysomia bezianna / Old world screw worm
Hypoderma bovis / Warble Fly
Tx
Manual removal, debridement
ML
Phototsensitization
Chorioptic Mange
Ax
Chorioptes bovis
Non burrowing mite, feeds on epidermal debris
LSD 🐄🐃 📣
BOLO
Sheep Scab
Ax
Multisystemic
Deep skin nodules
Respiratory tract
Oral Cavity
Mastitis, orchitis
Peripheral Lymphadenitis
Capripox, Poxvirus
CS (45% morbidity, 10% mortality)
Economic losses
10% mortaliity
Permenant hide damage, downgrading
Abortion due to pyrexia
Infertility
Marked milk reduction
Vet costs
Epidemiology
Summer, around water sources
Calves, exotic breeds
Transmitted through blood / saliva: biting insects, injections, ticks, water troughs. Also suckling / in utero
Pathogenesis
Localised swelling + lymphadenopathy
Viraemia -> vasclitis -> skin nodules
Pyrexia, nasal + ocular discharge, salivation
necrotic plaques in the mucous membranes
upper respiratory tract + oral cavity