Ectoparasites

Question 1

Flea LC

Answer 1

Arthropoda–> Insecta–> Siphonaptera (fleas)

Question 2

Cat Flea vs. Dog Flea

Answer 2

• CAT FLEA IS COMMON

Question 3

Tick LC

Answer 3

Question 4

Lice LC

Answer 4

ENTIRE LC ON HOST

Pediculosis (heavy Infestation)–> anaemia

Question 5

Tapeworm Intermediate Hosts

Answer 5

• fleas
• lice (phthiraptera)

Question 6

Chewing lice vs. Blood Sucking Lice

Answer 6

Question 7

Nuisance Fly

(MUSCA)

LC

Answer 7

• M. domestica* (house fly; in- and outside animal buildings)
• M. autumnalis* (face fly; numerous outdoors, esp. cattle
• Sponge-like labellum mouthparts (sick up enzymes & suck up digested food)

Question 8

Ceratopogonidae culicoides

(MIDGES)

Answer 8

Question 9

“sweet Itch”

Answer 9

• caused by female midge bites
• seasonally occurring allergic dermatitis (immediate type hypersensitivity)
• vector for viral and parasitic infections

Question 10

Biting Flies

(Myasis)

Answer 10

Parasitism of living animals by dipteran larvae (maggots)

Types :

Facultative (optional)- parasitic lifestyle isn’t essential to life cycle e.g. blowflies–> Fly strike

Obligatory- parasitism= essential e.g. warble flies, horse bot flies, screw-worm flies

• Cutaneous, nasal & somatic taxonomy refers to where the parasitism occurs on the host

Question 11

Horse Bot Fly (Gasterophilus spp.)

Answer 11

Question 12

Blowfly (Calliphoridae)

Answer 12

Question 13

Tick Mouthparts

Answer 13

• Palps- sensory organs- detect temperature & CO2- to help locate capillaries
• Chelicerae- puncture through the skin
• Hypostome- tube for sucking host blood, backward pointing teeth

Question 14

Argas spp.

Answer 14

Argas spp.- Infect birds in warmer climates (also humans)

• A. persicus, poultry tick (or “tampan”), lives in crevices in poultry houses
• Feeds at night production loss + death (large numbers)
• Found on migratory birds in temperate regions

Epidemiology- In tropical / sub-tropical climates

Ticks may be active all year round

If limited vegetation mat activity influenced by seasonal rainfall (due to their need for ↑ RH)

Question 15

SARCOPTES (BURROWING MITES)

LC

Answer 15

• Veterinary Importance: PARASITIC
• skin disease cause
• SARCOPTIC MANGE: Erythema with papule formation, Scale + crust formation + alopecia. Intense pruritus (1 week) + self-inflicted trauma + scab formation
• most of LC is on the host

Question 16

PSOROPTES (SURFACE MITES)

Answer 16

• Surface mite; active in keratin layer of skin probing with piercing mouthparts
• Several different “species” occur on domestic animals: (sheep scab= most important)
• • Ps. ovis (sheep, cattle), Ps. equi (horses), Ps. cuniculi (rabbits, horses), also occurs on camelids
• LC: confined to skin surface
• PSOROPTIC MANGE: important with sheep. winter disease (maybe late summer). mites under scabs and skin folds (can get bad)
• feed on serous exudate after pricking skin surface
• antigens in mite faeces–> Hypersensitivity reaction
• DIAGNOSE: skin scraping
• COntrol: plunge-dipping in OP’s