CLASS ARACHNIDA

Class: Arachnida
Order: Acarina

• Species are soft and hard ticks, and minute relatives called mites

• Can cause mange or other injuries

• Segmentation of body is absent

• Mouthparts: a pair of chelicerea, pair of pedipalps, in between is a median toothed structure called hypostome

Mouthparts

A pair of chelicerea, pair of pedipalps, in between is a median toothed structure called hypostome

Life stages

Eggs - larva (six legs) - nymph (no sexual organs) - nymphal instars (protonymph, deutonymph, tritonymph)

Mite infestation sites on skin

1. Psoroptic mites - infest ear / dense hair or fur

2. Sarcoptic mites - upper layer of skin

3. Demodectic mites - hair follicles and sebaceous glands

4. Dermanyssid mites - exposed areas of skin

Family: Dermanissidae
Genus: Dermanyssus

Dermanyssus gallinae - red mite of poultry
Red when recently fed, otherwise, whitish, greyish, black
Whole life completed in 7 days

• eggs laid after meal, up to 7 eggs

• hatch in 48-72 hrs, six legged larvae

• moult in 24-48 hrs to become protonymph

• become deutonymph after 24-48 hrs

• after 24-48 hrs blood meal, become an adult

Dermanyssus gallinae

• adults can live for 4-5 months without a meal

• reproduce rapidly

• can cause anemia, & irritation

• Vector of Borrelia anserina, fowl spirochaetosis

Parasite (Dermanyssus gallinae) found naturally infected with the virus of

• St. Louis encephalitis

• Eastern encephalitis

• Western encephalitis.

How to control Dermanyssus gallinae?

• Nest should be removed

• Amitraz (pesticide)

• Sprays of Malathion

• Chlordane

• Aerosol spray

Othe important mites

1. Northern mite - Ornithonyssus sylviarum

2. Tropical fowl mite - Ornithonyssus bursa

3. Tropical rat mite - Ornithonyssus bacoti

4. House-mouse mite - Allodermanyssus sanguineus