Ectoparasites

Question 1

What is a parasite?

Answer 1

Lives at the expense of another organism (host) long term, without causing immediate death of the host

Question 2

What are some detrimental effects of host-parasite relationships?

Answer 2

Anaemia, tissue damage, inflammation, allergic responses, weight loss

Question 3

What is tagmatization?

Answer 3

Formation of segmented hosts (usually head/thorax/abdomen different sections)

Question 4

What are the layers of the exoskeleton (deepest-superficial)

Answer 4

Basement membrane –> epidermis –> endocuticle –> exocuticle –> epicuticle (with waxy layer)

Question 5

Through which structures do ectoparasites respire?

Answer 5

Spiracles and tracheoles (stigmata in ticks/mites)

Question 6

What is the mouthpiece of a mite called?

Answer 6

Gnathosoma

Question 7

What is the body of a mite called?

Answer 7

Idiosoma

Question 8

What are the symptoms of scabies (sarcoptes)?

Answer 8

Intense itching and inflammation, hair loss, crusts of dried exudate, hypersensitivity

Question 9

Which species typically get sarcoptic mange?

Answer 9

Dogs and pigs, rarely seen in livestock/cats/horses

Question 10

Where do dogs typically get sarcoptic mange infestation?

Answer 10

Pinnae, elbows, ventrum

Question 11

What is otodectes cyanotis/what gets it?

Answer 11

Ear mites, hosts are cats/dogs/other carnivores (e.g. foxes)

Question 12

What/where is demodicosis?

Answer 12

Demodex mites, obligatory, deep in dermis (only found via deep skin scraping/hair plucks)

Question 13

How are demodex mites usually passed on?

Answer 13

From dam to young with suckling,

Question 14

What are Cheyletiella?

Answer 14

Large zoonotic mites, can infect rabbits/cats/dogs, can survive 10 days off host

Question 15

Do male or female ticks have the larger shield?

Answer 15

Males

Question 16

What is the activity called where ticks are looking for a host?

Answer 16

Questing

Question 17

What is the most common tick in the UK

Answer 17

Ixodes ricinus

Question 18

How many hosts does Ixodes ricinus have by the time it grows to adult size?

Answer 18

3

Question 19

What is the basic life cycle of the flea?

Answer 19

Egg –> larva –> pupa –> adult

Question 20

How can fleas also transmit Dipylidium caninum (tapeworm)?

Answer 20

Larvae will feed on organic debris including tapeworm segments

Question 21

What provides stimulation for pupae to emerge from cocoon?

Answer 21

Increasing temperature or mechanical pressure

Question 22

How long can pupae remain dormant for?

Answer 22

Up to 6 months (but usually only 5-10 days)

Question 23

What are the 2 types of lice?

Answer 23

Sucking louse and chewing louse

Question 24

How to tell which type of louse?

Answer 24

Sucking louse = small head

Chewing louse = large flat round head

Question 25

What is Trichodectes canis?

Answer 25

Chewing louse of dogs - found in puppies head/neck/tail

Question 26

Which ectoparasites can also be intermediate hosts for Dipylidium caninum?

Answer 26

Fleas and chewing lice (dogs)

Question 27

What is Gasterophilus spp.?

Answer 27

Flies found on horses

Question 28

What is a myiasis affecting rabbits?

Answer 28

Rabbit strike (Lucilia sericata)

Question 29

What are some possible infestations in rabbits?

Answer 29

Blowfly strike
Myxomatosis 
Mange mites 
Coccidia 
Encephalitozoon coniculi

Question 30

What is canine leishmaniosis? Where does it come from?

Answer 30

Myiasis, carried by sand flies, from abroad (mediterranean)

Question 31

What are Culicoides midges?

Answer 31

Sweet itch, found on horses worldwide

Vectors of many viruses and nematodes

Question 32

What is different about the life cycle of a midge?

Answer 32

Larva are aquatic