Transmission
- Close contact
- Adults and larvae can be transferred from one skin surface to another
Pathogenesis
- Erythema with papule formation
- Scale and crust formation
- Alopecia
- Intense pruritus for 1 week
- Self-inflicted trauma
- Scab formation
- Wrinkling and thickening of skin
- Hypersensitivity may develop
- Rash develops
Sarcoptes scabiei
- Causes scabies
- Strains of S. scabiei can be passed between different animals and cause clinical signs although the infection is likely to resolve spontaneously and be unlikely to establish
Diagnosis
- Skin scraping until capillary blood appears
- Adults, eggs, immature mites and faecal pellets can be seen microscopically
- Place material on a microscope slide
- Add 10% KOH
- Warm slide over bunsen flame
Treatment
- Acaricide
- For more information on acaricides click here
- Treat both infected and in-contact animals
- Older products have to be given in repeat treatments
- Avermectins are effective in farm animals
- Selamectin is available as a good spot-on for dogs
Cats
- Rare
Pigs
- Important condition, 35% pigs are asymptomatic carriers
- First signs of infestation appear on the ears before spreading to the rest of the body
- Transmission from sow to piglets whilst suckling and from boars to gilts at service
- Infestation adversely affects productivity
- Control for pigs:
- Treat sows before entering the farrowing pen
- Treat boars at 6 month intervals
Cattle
- Most frequently seen in housed cattle
- Notifiable in USA and Canada
- Often called 'neck and tail mange' as lesions most often seen on neck and tail
- Infestation adversely affects productivity
Sheep
- Notifiable in UK
- Lesions on hairy parts of face
- E.g. Face, ears, axillae and groin
- Causes considerable hide damage in local African breeds of long haired sheep
Horses
- Notifiable in UK
- Lesions begin on head, neck and shoulders then spread to rest of body