ENI - Lice Flashcards
Describe the general features of lice
- Phthiraptera
- Hemimetabola
- Live close to skin
- Lay eggs
- Highly specialised
- Limited/single host species range
- Split into chewing vs sucking lice
Describe the basic morphology of lice
- Claws
- Dorso-ventrally flattened
- Wingless
- Mouthparts adapted to chewing or sucking
Describe the appearance of louse eggs
- Pale, translucent
- Suboval
- Firmly glued to hairs near skin
- Chicken lice lay eggs in large maasses at base of feathers
How are lice transmitted?
Direct contact
Describe the 3 types of lice found on humans
- Head, body, pubic
- Head and body are different morphotypes of the same species
- Head: Pediculus humanus capitus
- Body: Pediculus humanus corporis
- Pubic: Phthirus pubis
What are the suborders of lice?
- Anoplura (sucking lice)
- Rhynchophthirina (elephant and warthog lice)
- Amblycera and Ischnocera (chewing lice)
Name the genuses of sucking lice
- Haematopinus
- Linognathus
What are the host species for Haematopinus?
- Pigs
- Cattle
- Horses
What are the host species for Linognathus?
- Cattle
- Sheep
- Goats
- Dogs
Name the genuses of chewing lice
- Damalina (Bovicola)
- Felicola
- Trichodectes
- Lipeurus
- Cuclogaster
- Menacanthus
- Gliricola
- Gyropus
What genus of chewing lice are found in cattle, sheep, goats and horses?
Damalina (Bovicola)
What genus of chewing lice are found in cats?
Felicola
What genus of chewing lice are found in dogs?
Trichodectes
What genuses of chewing lice are found in domestic birds?
- Lipeurus
- Cuclotogaster
- Menacanthus
What genuses of chewing lice are found in guinea pigs?
- Gliricola
- Gyropus
Describe the common appearance of sucking lice
- Often found with mouthparts embedded in skin
- Relatively large
- Often at 45degrees to skin (feeding)
Describe the common appearance of chewing lice
- Fairly active
- Not embedded
- Can be seen moving through hair of host
What is pediculosis?
Infestation of lice
What are the direct effects of pediculosis?
- Pruritus
- Dermal irritation
- Unthrifty appearance
- Rough coat
- Lowered production in farm animal
- Loss of hair and local scarification
- Severe infestations of sucking lice may lead to anaemia
What are the indirect effects of pediculosis?
- Can act as vectors
- Rickettsia prowazekii (typhus)
- Borrelia recurrentis (louse-borne relapsing fever)
- Bartonella quintana (trench fever)
- Swine pox
- trichodected can be intermediate hosts for Dipylidium caninum
Outline lice and large animals
- Infested animals bite, scratch and rub selves
- Causes self-truama
- May damage fences, trees and buildings
- Welfare and economic considerations
- Damage to hide downgrades value of leather
- Weight loss, poor milk production
- Anaemia likely if large numbers of lice involved
- Usually seen on stressed, underfed or unwell animals
Outline lice in small animals
- Not common pest of companion animals
- Mainly rescues, puppy or kitten farms
- More common in elderly
- Poor health, long coat predispose
- Some species more irritating that others
Outline lice in birds
- Not highly pathogenic to adult birds
- May be fatal to chicks
- Damaged skin = secondary bacterial infections
- Restlessness, feather plucking, feather damage, cessation of feeding, death
Outline the control of lice
- Spread by direct contact so limit
- Adults, nymphs and eggs only survive few days off host
- Control uncomplicated as most time on host
- Need to consider sucking vs chewing, timing and treatment method
- Treat all animals at once
- Spot ons, pour ons, powers
Describe the appearance of Felicola subrostratus
- Distinct triangular head
- Legs for grasping
- Thorax
- Large rounded abdomen, pointy at end
Describe the appearance of Linognathus
- Thin pointed head
- More rounded legs
- ## Elongated/oval abdomen
Describe the appearance of chewing lice
- Flat/rounded head
- Mouthparts less obvious
Describe the appearance of Haematopinus suis
- Similar to Felicola
- Claws obvious on feet
- Dots around outside of abdomen
