Nematode: Ascaridida Flashcards
What are the general characteristics of Ascarids?
Roundworms Host specific Large white nematode with 3 lips Adults small intestine Eggs thick walled Direct life cycle
What methods of transmission can be observed in Ascarids
Per os
Transmammary
Transplacental
PH
What is the infective stage of Ascarids?
L2 or L3 in egg
List ascarid species
Toxocara canis Tosascaris leonia Toxascaris cati Baylisascaris procyonis Parascaris eqquorum Ascarids suum
Host of toxocara canis?
Dogs
Zoonotic
Identify
Adults 10-12cm, round white
Egg: dark brown, round, thick pitted shell
Dog
Toxocara canis
Life cycle of Toxocara canis?
4 modes of infection Per os Transplacental Transmammary PH
Egg to egg with L3
L3 hatch cross intestinal wall migrate to liver
Pulmonary capillary
Somatic tissue
Direct
Pathogenesis and clinical signs of Toxocara canis?
age, number, site?
Intestinal obstruction with large numbers -> pot bellied
Entire nematodes can pass in feces and vomit
Pups- prenatal or transmammary infections, can die from pneumonia
Vomit after each meal
Diagnosis of toxocara canis?
Clinical signs can be seen before eggs
Eggs in fecal float
Adult worms in feces/vomit/necropsy
Treatment and control of toxocara canis?
Treat pregnant botch
Treat puppies (2, 4, 6, and 8wks)
Kill L4 and immature adult stances
Toxocara canis can cause _____________ in humans?
Visceral larval migrans and ocular larval migrans
Toxocara cati host?
Cat
Zoonotic
Modes of infection of toxocara cati?
Per os
Transmammary
PH
NO transplacental = seen in slightly older kittens
Host of toxascaris leonia?
Cat and dog
Identify
Adults - round white, 6-2cm
Eggs -oval with smooth thick shell
Cat or dog
Toxascaris leonina
What are the modes of infection for Toxascaris leonina?
Per os
PH
How do the PPP of toxocara and toxascaris compare?
Toxocara 3-10wks
Tosascaris 10-12wks
Ascaris suum 4-wks
Parascaris equorum 10-12wks
Host of Baylisascaris procyonis?
Raccoons
Zoonotic with high level of VLM
Can infect dog
Host of parascaris equorum?
Equine
Mode of infection of parascaris?
Per os
Host of asaris suum?
Pig
PH earthworm
Zoonotic
Mode of infection of ascaris suum?
Per os
PH
Identify
Adult
Round, white, 40cm
Egg : round, thick shell, mammilated, 50um
Pig
Ascaris suum
Milk spots on the liver of a Pig are characterisitic of what parasite?
Ascaris suum
Pathogenesis and clinical signs of Ascaris suum?
Heavy infection- transient pneumonia
Intestinal disturbances
Poor feed conversion; slow weight gain
Milk spots liver
Treatment and prevention of Ascaris suum?
Associated with both indoor and outdoor
Reduce/eliminate source: treat/wash sows pre-farrowing
Treat piglets at weaning
Feed-through anthelmitics
What are the general characteristics on Heterakoidea?
Oval thick shelled egg Small and large intestine Large and small parasites PH can be involved Infective L2
Ascaridia spp common name?
Roundworm
Hosts to Ascaridia spp?
Domestic and wild birds, CHICKEN
PH: Earthworms
Identify
Bird
Round white worm 8-12cm
Egg- oval thick-shelled (80umx60um)
Ascaridia spp.
Site of infection of Ascaridia spp?
Small intestine
What is the pathogenesis of Ascaridia spp?
Weight loss
Obstruction of small intestine
How do you diagnosis
Eggs in fecal examination
Necropsy
What is the common name of Heterakis spp?
Poultry cecal worm
Hosts of Heterakis spp.
Domestic and wild fowl
PH: earthworms and flies
Site of infection of Heterakis spp?
Cecum
What is the infective stage of both Ascaridia spp and Heterakis spp?
Egg with L2
What is the PPP of Ascaridia spp?
4wks to 8wks
What is the PPP of Heterakis spp?
3-4wks
What is the signifcance of H.gallinarium infections?
The nematode itself is non-pathogenic but transmits Histomonas meleagridis which causes “blackhead” in turkeys
What is the best way to diagnose Ascaridia spp/ Heterakis spp
?
Eggs in fecal examination
Ascaridia eggs> Heterakis eggs
Necropsy
