Week 2: Lice - COMPLETE ****

Question 1

State the order for Lice

Answer 1

phthiraptera

Question 2

Anatomy: What key anatomical features do they have and how do some of these link to their function? 4

Answer 2

claws for gripping hairs
dorso-ventrally flattened
wingless
mouthparts adapted for chewing on epidermal debris or sucking blood

Question 2

What type of life cycle do they have?

Answer 2

hemimetabolous

Question 3

What are the 2 main groups of lice and give their scientific name too?

Answer 3

sucking lice - anoplura

chewing lice - mallophaga

Question 4

Anoplura: Which genus affects height-wise taller animals?
- state which animals these affect

Answer 4

haematopinus

cattle
horses
pigs

Question 5

Anoplura: Which genus affects height-wise smaller animals?
- What is one exception?
- State the other species it affects

Answer 5

linognathus

cattle

sheep
goats
dogs

Question 6

How can you identify suckling lice over chewing lice? 2

Answer 6

sucking lice are larger
they are often found with mouthparts embedded in skin

Question 7

Mallophaga: State the Genus for the dog chewing lice
- State the genus for the cat chewing lice

Answer 7

trichodectes

felicola

Question 8

Mallophaga: State the genus for the farm animal + horse chewing lice

Answer 8

bovicola

Question 9

Mallophaga: State the 2 different Genus of chewing lice affecting Guinaea pigs

Answer 9

giricola
gyropus

Question 10

Mallophaga: State the 3 different Genus of chewing lice affecting domestic birds

Answer 10

menacanthos
cuclotogaster
lipeurus

Question 11

How can you identify chewing lice over sucking lice? 3

Answer 11

chewing lice are more active
they are not embedded in the skin
they can be seen moving through the hair

Question 12

Describe the appearance of lice eggs 3
- where will they be found?

Answer 12

pale
translucent
sub oval

firmly glued to hairs near the skin

Question 13

How long is the life cycle of a louse?
- How are they transmitted?

Answer 13

3-4 weeks

by direct contact

Question 14

State the common and scientific name for the 3 types of louse affecting humans

Answer 14

head louse - pediculus humanus captus
body louse - pediculus humanus corporis
pubic louse - phthirus pubis

Question 15

Where do human body louse live?

Answer 15

they live on clothes
they crawl to the skin to feed 5 times a day

Question 16

State and explain a direct effect of Lice
- how does this negatively affect the animal?
- What clinical signs would you expect to see? 4

Answer 16

pediculosis which is an infestation of lice

it can cause dermal irritation

pruritus
unthrifty appearance
rough coat
loss of hair

Question 17

State an indirect effect of human sucking lice
- Give examples of types of diseases they can spread 3
- Give an example of an animal louse and give a disease it can spread

Answer 17

mechanical spread of diseases

typhus
louse-borne relapsing fever
trench fever

the pig louse is a mechanical vector for swine pox

Question 18

Large Animals: How would a lice infestation manifest itself in behavioural changes? 3
- Why can this be problematic economically? 2
- What clinical signs would you expect to see in a severe infestation? 3

Answer 18

biting
scratching
rubbing

it can cause damage to fences trees and buildings
it can damage hide which downgrades leather quality

weight loss
poor milk production
anaemia

Question 19

Small animals: Is a Lice infestation common in domestic animals?
- Which small animals would be most likely to develop a lice infestation? 3

Answer 19

no

elderly animals
animals in poor health
longhaired breeds unable to groom themselves

Question 20

Birds: Which life stage bird would be most severely affected by a lice infestation?
- What are some of the consequences to a lice infestation and what can they lead to? 2
- What could predispose a chick to experiencing a more severe lice infestation and why?

Answer 20

chicks

damaged skin may lead to a secondary bacterial infection
irritation leading to restlessness, feather plucking and cessation of feeding

beak trimming as the chick would be unable to properly groom itself

Question 21

Control: Why is control of lice very straightforward? 3

Answer 21

because lice can only survive a few days off the host
so they spend their whole life cycle on the host
so the environmental control is not required

Question 22

Control: what factors do you need to consider when treating animals for lice? 3

Answer 22

are they sucking or chewing lice
timing of treatment
treat all animals at the same time

Question 23

Control: Give an example of a treatment for Horses
- What other products are available for lice treatment in animals?

Answer 23

deosect

spot ons