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Flashcards in SA/EQ Ectoparasites Deck (89):
1

Nuisance flies are of the which family of Diptera?

Muscidae

2

What are the feeding habits of the Muscidae family?

They feed on bodily secretions or suck blood

3

How does the morphology of T.tabanus and T.haematopota differ?

Tabanus has clear wings whereas haematopota has mottled colored wings

4

Tabanidae species can be vectors of which major diseases/ parasites?

  • Equine infectious anaemia
  • Bacillus anthracis
  • Trypanosomes evansi

5

This pool feeding fly breeds in wet pasture or marsh lands and causes gadding in cattle through July and August.

tabanidae tabanus

6

Which species of Muscidae causes sweet itch in horses?

Culicoides spp.

7

Sweet itch is also known as ?

Seasonal recurrent dermatitis

8

How long does it take for culicoides to develop from egg to adult?

About three weeks

9

Culicoides species can act as a vet to for which major diseases?

  • African horse sickness
  • Blue tongue
  • Schmallenberg
  • Protozoa/ nematodes

10

Simulium flies are also known by which name?

Black fly

11

Name the two main species of culicoides flies.

  • Imisola
  • Obsoletus

12

Non- biting Muscidae feed upon what from its host?

Bodily secretions:

Saliva

Tears

Milk

13

This non-biting Muscidae fly can be identified by its orange wing base and olive abdomen. It causes August bag in dairy cattle.

Hydrotaea irittans

14

How many life cycles will a culicoides go through a year?

1

15

Gasterophilus species are more commonly known as what?

Bot flies

16

Name the three main species of gastrophilus flies.

  • Intestinalis
  • Nasalis
  • Haemorrhoidalis

17

Male culicoides feed upon what?

Nectar

18

This non-biting Muscidae is characterised by a wing vein tick. It is also known as the face fly.

Musca autumnalis

19

What is the ideal environment for stomoxys calcitrans to breed?

  • Dung
  • Old feed
  • Decaying matter

20

What is gadding?

Restless/ agitated behavior in response to fly bites

21

Why are the bites of stomoxys calcitrans very painful for the horse?

Their have a long pointed proboscis

22

How can stable fly attacks be minimalised in the horse?

Regular application of pyrethrins, eliminating breeding sites (dung, old bedding), repellents, barriers to flies.

23

What clinical condition are black fly seen to cause?

Aural plaques

24

  1. This type of ectoparasiticide targets the AchE enzyme of the parasite.
  2. What effect does this have?

  1. Organophosphates
  2. Causes accumulation of neurotransmitter therefore leading to paralysis. Can be toxic to other species.

25

Synthetic pyrethroids have natural analogues which originate from which plant?

Chrysanthemum

26

  1. Outline the mode of action of synthetic pyrethroids.
  2. Which parasite are they used to target?

  1. Cause depolarisation of cell membranes via voltage-gated Na+ channelsand therefore paralysis.
  2. Lice and ticks.

27

  1. Moxidectin is an example of which class of parasiticides.
  2. What are they used against?

  1. Macrocyclic lactones - milbemycins They are endectocides - effective against lots of
  2. Arthropoda and nematodes.

28

This ectoparasiticide stimulates the release of GABA NT leading to hyperpolarisation of the NS of the parasite. It is highly lipophilic and therefore persists within the body.

Macrocyclic lactones

29

Which insect growth regulator acts to inhibit normal chitin synthesis?

Insect development inhibitors

30

Name an insect development inhibitor which is used in the control of blow flies for up to 14 weeks.

Triazine derivatives, cyromazine

31

Name a juvenile hormone analogue.

Methoprene

32

This flea adulticide targets nicotinic ACh receptors of the parasite.

Imidacloprid - a neonicotinoid

33

Explain why fipronil has a long residual activity.

It diffuses into hair follicle associated sebaceous glands therefore acting as a reservoir .

34

  1. This ectoparasiticide is used against sarcoptes and demodex and acts at octopamine receptor sites.
  2. What does their action cause?

  1. Amitraz
  2. Causes neuronal hyperexcitability and death

35

Describe the external features of Arthropoda.

  • An external waterproofed skeleton made from alpha chitin.
  • A segmented body.
  • Jointed limbs.

36

Myiasis

Laying of eggs by flies which hatch and burrow into the host.

37

Which type of ectoparasite lifecycle is more difficult to hold?

Permanent or temporary?

Temporary

38

Ectoparasite circulatory system.

Haemocoele

39

Spiricles

Holes in the side of the insect used in respiration.

40

Mechanical digestion of food in insects occurs in which organs?

Foregut, crop, proventricles

41

What is the function of the makpighian tubules of an insect?

Filters waste from haemolymph into the gut.

42

What is the difference between holometabolous and heminetabolous

  • Holo = complete metamorphosis
  • Hemi = incomplete metamorphosis

43

What is the structural difference between a tick nymph and adult?

Nymph has only six legs whereas the adult has eight.

44

Name the different parts and function of the haemtopota mouthpart.

  • Palp Labrum - upper lip
  • Mandible - cutting/ slashing
  • Hypopharynx - tongue like
  • Maxillae Labium/ labellum - Lower lip

45

Describe the specialised mouthpart of H. irritans.

Sponging

For secretions, not blood

46

What is the function of the hypostome of the tick?

Secretes cementing factors and anticoagulant.

Has serrated spines to anchor them to the skins.

47

Name the three feeding habits of different types of mite and give an example for each.

  1. Skin burrowing - sarcoptes
  2. Follicle - dwelling - demodex
  3. Surface feeding - psoroptes ovis (sheep scab)/ Cheyletiella
  4. Obligate blood suckers - poultry red mite

48

A pool feeding fly which breeds in wet pasture, marshy lands and edges of ponds and ditches.

Tabanids

49

Causes gadding in horses during July/ early August.

Tabanids

50

Pruritis caused by culicoides is caused by what?

Hypersensitivity to culicoides saliva.

51

African horse sickness is an example of which type of virus?

Orbivirus

52

This species of culicoides is the vector of bluetongue in Northern Europe.

C. imicola

53

This species of fly lay their eggs in rivers which hatch into aquatic larvae that depend on flowing water.

Simulium spp.

54

Simulium are vectors of which diseases?

River blindness - Onchocerca

Leucocytozoon - Geese and ducks

55

Describe the behaviour of S. calcitrans.

Rest/ mate on sun exposed walls

Feed on lower parts of the animal

56

S. calcitrans acts as a vector for which diseases?

  1. Equibe infectious anaemia
  2. Anthrax
  3. Habronema
  4. Bovine viral diarrhoea

57

Name the three main non-biting muscidae.

  • H. Irritans - headfly
  • M. Autumnalis - facefly
  • M. Domestica- housefly

58

This species of fly does not enter buildings and is mainly found in overcast, warm and humid August days.

H. irritans

59

Name the species of gastrophillus and describe where each lays their eggs on the horse.

  • Intestinalis - inner forelegs and hocks
  • Nasalis- laid under the jaw
  • Haemorrhoidalis- lips

60

Outline the basic lifecycle of G. intestinalis.

Eggs ingested, burrow into tongue, moult and exit to pharynx, moult to L2, migrate to oesophageal stomach, moult to L3 remain until spring, passed in the dung and mature to adults.

61

How can gastrophillus infections be controlled?

Ivermectin or moxidectin infections

Removal of eggs

62

Pediculosis is caused by which mite?

  • The disease is characterised by which clinical symptoms.

Trichodectes canis

  • Mites on head, neck and tail 1cm eggs can be seen on hairs
  • Alopecia
  • Excoriation
  • Inflammation

63

Describe the morphology of Trichodectes canis

  • Small (1-2mm)
  • Yellow dark marks on abdomen
  • Claws to grip hairs

A image thumb
64

How long can Trichodectes canis survive off the host?

7 days

65

Mites have what type of lifecycle complete or incomplete?

Incomplete lifecycle, they go through 3 nymph stages.

66

Name this rare sucking louse of cats and dogs.

Linognathus stetosus

67

Describe morphology and distribution of Felicola subrostrata.

Triangular shaped head

Cause lesions on the face, pinnae and back.

A image thumb
68

1. This ectoparasiticide disrupts the CNS of the parasite by blocking GABA and other ligand-gated chloride channels.

2. How long does it persist in the body?

3. How long does it take to kill fleas and lice?

1. Fipronil

2. 60 days but weakens

3. 24 hrs to kill fleas and 48hrs to kill lice

69

Imidacloprid blocks which type of neurotransmitter channel?

Nicotinic acetylcholine receptors

70

1. Fluralaner is an example of which type of ectoparasiticide?

2. What is this classes mode of action?

3. How do they distribute in the body?

1. Isoxazoline

2. Inhibitors of CNS, blocks GABA and glutamate channels, they target newly emerging fleas

3. Systemic, particularly in fat.

71

Describe the lifecycle of the flea.

1. Eggs - laid on host and fall off into environment

2. Larvae - 3 larval stages - they are positively geotactic (move in response to gravity)

3. Pupae - pre emerging adults - can wait up to 6 months

4. Adult fleas - live permanently on the host - lay eggs 48hrs after infestation

72

Cat scratch disease is caused by which pathogen spread by cat fleas.

Bartonella

73

How do fleas become a vector for Dipylidium canium?

D. canium disintegrates to produce eggs, flea ingests egg pockets, tapeworm develops.

74

How can a flea investation be diagnosed?

1. Flea dirt dehydration2. Signs of flea allergic dermatitis - alopecia, excessive grooming, skin damage 3. Visible signs

75

What taxonomic group do fleas belong to?

Insecta > Siphonaptera > Ctenocephalides (canis/ felis)

76

Describe the morphological features of a flea.

Dark brown Wingless

Laterally compressed

Head combs (pronotal and genal)

77

What environmental parameters are required for flea development?

>70% relative humidity

78

How does the morphology of the two equine lice Mallophaga and Anoplura differ

Mallophaga wide head to body whereas anoplura has a narrow head compared with body

79

Describe the lifecycle of the louse.

1. Eggs - hatch after one to two weeks2. Larva - 3 instar stages3. Adult - lay 200-300 eggs per month on hair/ feathers

80

1. Name two lice found on horses2. Where are they usually found on the body?

1. Haematopinus asini (sucking), Bovicola equi (biting and chewing)2. Dense hair at the tail and mane base

81

1. Cypermethrin shows what type of isomerism?2. How often does its treatment need topping up?

1. Optical - it is 50:50 cis/trans mixture2. 2-4 weeks

82

This ectoparasiticide works as a neuropoison of axons of CNS and PNS using Na channels.Which species should you be wary of when using it?

PermethrinFish

83

Differenciate between the morphology of psoroptic and chorioptes.

Psoroptic have trumpet suckers whereas chorioptes have cup shaped suckers.

84

Which type of lice causes sheep scab and severe disease in sheep and cattle?

Psoroptic spp.

85

How may Chorioptes bovis/equi be treated?

Selenium sulphide or fipronil

86

How long can chorioptes survive off the host?

Up to 3 weeks

87

Which gender of Tabanidae is pool feeding?

Female

88

Dog and cat fleas belong to which taxomic group?

Ctenocephalides

89

Name the main types of pharmacological agents used as ectoparasiticides.

MASON PII

Macrocyclic Lactones 
Amidines
Synthetic pyrethroids 
Organophosphates 
Neonicotinoids

Phenylprazoles
Isoxazolines
Insect growth regulators (JGA and CSI)