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

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

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