Non Bursate Nematodes Flashcards
List the superfamilies of non bursate nematodes
Rhabditoidea (threadworms) Ascaridoidea (round worms) Oxyuroidea (pin worms) Habronematoidea ( tight spiral tail things) Filaroidea (worms in circulatory system) Trichinelloidea (L1 infective stage)
Rhabditoidea
strongyloides (threadworms) only females are parasite 5-6mn in SI villi significant in very young horses, pigs and ruminants
Ascardoidea
round worms
in SI
Thick and sticky eggs –> persist in the environment
L3 develops in egg
pathogenesis = ill thrift (slowing growth rate), diarrhoea, respiratory signs from migrating larvae.
can be zoonotic, when embryonic eggs ingested (ocular larva migrans or visceral larvae migrans
Oxyuroidea
pin worms; blunt anteriorly, sharp posteriorly
Large intestines
direct life cycle
host specific
Habronematoidea
Indirect lifecycle –> arthropod hosts
Males have tight spirally coiled tail
Filaroidea
Adults in circulatory system or CTs, mircofilariae taken up by parasite insects
adult makes have loose spiral tail
Trichinelloidea
has the whip worm
L1 infectious stage (different to others)
Stichosome or trichuroid oesophagus
List the species of Rhabitoidea
Strongyloides ransomi (pig) Strongyloides Westeri (horse, foals)
List Ascaridoidea species
Toxocara canis (dog)
Toxocara cati
Parascaris equonum
Ascaris suum
List the species of Oxyuroidea
Oxyuris equi
Enterobius vermicularis
List species of Habronematoidea
Draschia Megastoma
Habronema species
list species of Filaroidea
Dirofilaria Immitis (canine heartworm)
Dipetalonema reconditi
Onchocerca spp
list species of Trichinelloidea
trichuris spp (whip worms)
Strongyloides ransomi
pig thread worm
Rhabitoidea
larvae transferred w/colostrum
piglets infected within 24hrs of birth (severe loss)
intestinal disease 2-4wks after infection
good husbandry reduced in clean piggeries
Strongyloides Westeri
horse and foal
Rhabitoidea
homogonic stage - pathogenic females in inestine
eaten or penetrate skin
Toxocara canis
Dog round worm Ascardoidea ILL thrift, vomiting, diarrhoea, intestinal obstructions pot belly puppies 10-18cm
Toxocara cati
Cat roundworm
Ascardoidea
3-10cm
parascaris equonum
15-50cm horse round worm
Ascardoidea
Ascaris suun
- 20-40cm
adults in SI
tracheal migration after eggs ingested
ascardoidea
Oxyuris equi
horse pinworms
oxyuroidea
itching and irritation around anus, eggs laid around the anus
Enterobius vermicularis
human pin worms
Oxyuroidea
Drachia megastoma
horse
habronematoidea ( has an indirect lifecycle with arthropods)
in colonies within nodes in wall of equine stomach
Dirofilaria immits
Canine heart worm
Filaroidea
- adults in pulmonary arteries
12-30cm
congestive heart failure, pneumonitis, renal disease
low worm burdens = no circulating micofilariae can complicate diagnosis
Dipetalonema reconditum
Filaroidea in dogs
Adults in body cavity CT or kidneys
not clinically significant
Onchocerca spp
cattle and horses adults in CT, often in nodes micofilariae in skin midges - intermediate host allergic skin reactions in horses, condemnation of carcasses
Explain Trichuris
SF Trichinelloidea
whipworms
adults in LI/caecum of dog, pig, ruminants, people
long anterior, short. broader posterior
direct life cycle
Large burden can produce Large intestinal diarrhoea
Rhabditoidea general lige cycle
Egg in faeces L1 -L2 free living L3 skin penetration, ingestion (enters blood) L4 tracheal migration adult in SI
Toxocara canis life cycle
Habronema life cycle
Eggs in faeces L1 eaten by maggots L3 emerges from fly mouth, goes onto host lips L4 Adults ingested
Dirofilaria immures life cycle
Adult in the heart produce offspring after 3-4 months in 6-7mths it develops into microfilariae ( ingested by mosquito) penetrate bite wound into CT 3-4 days = L4 in CT 2-3 months = adult in the heart
