Date post: | 12-Jan-2016 |
Category: |
Documents |
Upload: | alicia-mason |
View: | 217 times |
Download: | 0 times |
Is it sheep Scab?
C S Parker BVM&S DBR MRCVS
Sheep scab
<1992 < 100 outbreaks per year Deregulation 1992 Everywhere except Australia/ N Zealand 100% morbidity
Sheep scab
Intense pruritis Rub shoulders or flanks
along ground Clawing/biting 1-5mm sores Serous exudation
exudate
Large areas develop 5 – 40 cm Shoulders + dorsum
Chronic Lesions
Skin becomes thickened
Flake like scabs Thick walled abscesses Can have seizures
Side effects
Seromas Fluid filled swellings Myositis Aural haematomas
Age & species
More severe in lambs & yearlings.
Different strains mites Long heavy fleeces Chronic carrier states
Treatments
Ivomec Dectomax Cydectin
Sheep scab
Chorioptic Mange
Chorioptic Mange
Chorioptic Mange
Thought to be eliminated before 2001
Slow build up Not seen in lambs
Chorioptic Mange
Itchy feet fetlocks Scrotal lesions
Forage mites
Late summer Quite itchy Grass or infected forage
Fly strike
Fly strike
Headflies
Feed on wounds Base of polls of young
sheep Active June to
September
Keds
Wingless flies 5 -7mm long Live on host Build up in Autumn &
Winter Scottish Islands
Lice
Increased as dipping decreased.
25% flocks infected Populations fall in Hot
or wet weather Eggs on fleece Itchy feet
Lice
Non Parasitic Diseases!
Photosensitisation
Plocteach! Movement poor to lush
pasture Excess dietary
Chlorophyll Skin active poisons- St
Johns Wort!
Photosensitisation
2ndry to liver disease Inherited condition in
Southdown & Corriedale
10% effected in some Scottish flocks
Bog Ashphodel
Photosensitisation – clinical signs
Wool free areas + midline of spine?
Anorexic, mildly itchy Lambs loose condition Oedema of face Seepage of fluid with
yellow crusts
Wool Slip
Large symmetrical areas wool loss
Common in winter shorn housed sheep
Stress induced No skin signs
Trauma !!
Chemical burns – phenolic dips
Scab sheep more susceptible
Orf
Needs contact with scabs +break in skin
Young lambs teeth errupting
Lasts 4 – 6 weeks Can have PI animals No colostral immunity
Orf – clinical signs
Reddening + swelling Scabs shed at 3 weeks Cycles of proliferation &
repair Muzzles lips teeth in
lambs or weaned lambs
Orf atypical lesions
Base of teats Ears Coronary band +
fetlocks Around genitals
Dermatophilus
Lumpy wool Outbreaks follow
prolonged wet weather Ears + nose most
common Chronic form scaly
areas on back Low grade pruritis
Pyodermas
Infected ulcers Face + eye area Tagging & troughs
Necrotic Dermatitis
Pseudomonas Prolonged soaking of
fleece Usually within 6 weeks
shearing Large ulcers under wool Foul green pus Internal abscesses fatal
Actinobacillosis
Skin thickening Multiple 5mm nodules in
skin of face, thick white pus
Kings Evil!
Caseous lymphadenitis
Lymph nodes
Ringworm
Crusty lesions on neck & ears
Combined lesions