Endoparasites

    Cards (29)

    • Direct Lifecycle
      parasite reaches sexual maturity on host or environment (e.g. fleas)
    • Indirect lifecycle
      Parasite requires another host for development (e.g. tapeworm)
    • Definitive Host
      where sexual reproduction of the parasite takes place
    • Intermediate host

      Essential for the parasite's lifecycle, where the parasite matures
    • Paratenic host

      Not essential for lifecycle but may contain parasite
    • What are trematodes?
      Flatworms/flukes
    • What are cestodes
      tapeworms
    • What are Nematodes
      roundworm, lungworm, pinworm, hookworm, bloodworm, etc.
    • What is the structure of a tapeworm
      - head (scolex)
      - segments (proglottids)
      - Maturing segments
    • How do tapeworms reproduce?
      - eggs develop in the segment
      - gravid proglottids usually shed from strobila and pass out with faeces of host
      - Eggs released into environment by disintegration of the segment or shed through opening in segment
    • What are the common tapeworms
      - Dipylidium caninum
      - Taenia spp.
      - Echinococcus spp.
    • Dipylidium Caninum
      - dog and cat tapeworm (cestode)
      - Fleas often act as the intermediate host
      - Flea larvae eat eggs of tapeworm ∴ if host swallows flea, worms are released into intestines
    • Taenia Species

      - more commonly in cats
      - intermediate hosts = birds, squirrels, mice, sheep etc.
      -Taenia Taeniaeformis= feline tapeworm (found in raw meat)
      -Taenia Hydatigena= canine tapeworm (from eating infected offal)
    • Echinococcus Granulosus
      - adult tapeworm found in dogs
      - eggs can survive in environment for a year
    • What is the structure of a roundworm
      - round in cross section
      - no segments
      - whitish or pinkish brown colour
      - taper at both ends
    • Toxocara Spp.
      - roundworms (nematodes)
      - may be spread by trans placenta and trans mammary routes
      - zoonotic
    • Toxocara Canis
      - Canine roundworm
      - Found in small intestine
      - zoonotic causes Human toxocariasis -> causes blindness after being ingested via contact with contaminated soil/faeces
    • toxocara canis routes of infection
      4 main routes of infection
      - via the environment
      - via the placenta
      - trans-mammary
      - via a paratenic host
    • Toxocara cati
      - Feline roundworm
      - similar to toxocara canis but distinguished by the alae(wings) on either side of head
    • toxocara cati routes of infection
      3 main routes of infection
      - via environment
      - via a paratenic host (development doesn't occur)
      - trans-mammary => milk NOT placenta
    • Toxoascaris Leonina
      - cat and dog roundworm
      - no pro-natal infection
      - 2 main routes of infection -> via environment, via paratenic host
    • Angiostrongylus Vasorum
      • Lungworm
      • adults live in pulmonary artery
      • Acquired from ingestion of infected snail
      • Damage to lungs/alveoli and potentially block pulmonary artery
    • General worming recommendations for puppies and kitten
      - from 2 weeks, should be treated every 2 weeks up to age of 12 weeks
      - Then, every 4 weeks up to 6 months of age
    • General worming recommendations for adult dogs and cats
      -atleast 4 times a year (every 3 months)
      - cats that hunt should be treated monthly
    • Fasciola hepatica
      - Liver fluke of cattle, sheep, and other ruminants
      - causes considerable tissue damage
    • Alaria Spp.
      - A. Canis and A. alata = intestinal fluke in dogs, cats, foxes and other wild carnivores
      - can cause haemorrhage and lung damage
    • Which cestode, not endemic in the UK, does the Pet Travel Scheme guard against?
      Echinococcus multilocularis (tapeworm)
    • What is toxocara canis' lifecycle
      • Direct lifecycle
      1. eggs passed into faeces
      2. eggs ingested
      3. larvae hatch in small intestine and penetrate wall
      4. larvae migrate to all organs via bloodstream
      5. adults live in animals small intestine
    • Clinical signs of toxocara
      • vomiting
      • diarrhoea
      • swelling of abdomen 'pot-belly' look
    See similar decks