Ascarididae, Toxocaridae, Oxyuridae, Anisakidae Flashcards
What are the two types of lifecycle of Ascaridoidea?
Somatic and Tracheal route of migration
Which larva is ingested by the host in the somatic route?
L3
Which Ascaris species may cross infect humans?
Ascaris lumbricoides
What is the infected site of A. suis?
SI
What does the lipid layer of the eggshell of A. suis contain?
ascarosides
Infection of A. suis is through ingestion of which larval stage?
L2
What are the paratenic hosts of A. suis?
beetle and earthworms
What is the route of migration of A. suum?
tracheal
What are the external signs of A. suis in pigs as disease progresses to pneumonia?
thumps or thumping
What are the three basic disease problems common in swine farms?
scouring, pneumonia, parasitism
What is the shape of eggs of Parascaris equorum?
sub spherical shaped
What is the affected site of P. equorum?
SI
What is the route of migration of P. equorum?
tracheal
What lesions are caused by P. equorum in equine liver?
white ribrous tracts
What is the route of migration of Neoascaris vitulorum?
Somatic
What is the host and predilection site of Toxocara vitulorum?
cattle and buffalo, small intestine
How may a calf be infected with Toxocara vitulorum through milk?
with L3
How long is T. vitulorum present in milk after parturition?
30 days
Which parasite is associated with Loffler’s syndrome?
ascaris
What are the modes of transmission of T. canis?
transmammary, transplacental, ingestion of infective egg or paratenic hosts
What is the host and predilection site of Toxocara canis?
dogs, SI
Which Toxocara species affects the SI of cats?
Toxocara cati
What are the modes of transmission of T. cati?
transmammary
What features may occur due to tracheal migration of T. cati?
liver fibrosis and lobular pneumonia
What is the common name of T. cati?
arrow headed worm of cat
Which Toxascara species affects the SI of dogs and cats?
T. leonina
How is T. leonina transmitted?
ingestion of paratenic hosts or by ingestion of L2
Which nematode species are associated with visceral larva migrans in humans?
T. canis, T. leonina, T. cati, bayliscaris procyonins, Strongyloides ransomi
Which Ascaris species may affect the CNS of pigs?
A. suis
What lesions are caused by visceral larva migrans?
chronic granulomatous
What do you call the system used to control Ascaridoidea infection?
McClean County system
What is the SN of the horse pinworm?
oxyuris equi
Describe the egg morphology of horse pinworm.
flattened side and has a mucoid plug
What are the pathogenic effects of oxyuris equi?
Sloughing of intestinal mucosa, anal pruritus
Which genera and species of Ascaridoidea do not have a migratory cycle?
Toxascaris leonina, Toxocara canis
What is known as the human pinworm or seatworm?
Enterobius vermicularis
What is the affected site of Enterobius vermicularis?
cecum, appendix, perineal region
Which Ascaridoidea genera and species is an unusual perpetual parasite?
Probstmayria vivipara
What Kathlanidae sp. affects the large intestine of horses?
Probstmayria vivipara
What is the mode of transmission of Probstmayria vivipara?
ingestion of larva through coprophagy
What is the most common and largest pig nematode?
Ascaris suum
What is the morphology of the male reproductive system of A. suis?
present spicule and precloacal papillae
Describe the egg morphology of A. suis.
oval, thick shells, prominent projections, brownish yellow
What are the characteristics of Parascaris equorum?
rigid stout worm with 3 main lips separated by 3 small intermediate lips
Describe the male reproductive system of Parascaris equorum.
tail has small lateral alae, 2 double and 3 single pairs of postcloacal papillae, with spicule
Where is the vulva located in P. equorum species?
end of the first quarter of the body
What members of this genus have a posterior granular ventriculus at the base of the esophagus?
Toxocara canis
Describe the eggs of Toxocara canis.
subglobular, with thick, finely pitted shells
What is the description of Toxocara cati?
large white worm, male has long finger like processes at the tip of the tail
What is the difference between Toxascara leonina and T. canis?
absence of finger like process at the tip of the male tail
Which species has their vulva open near the end of the first third of the body?
Ascaris suum
What is the morphological difference of T. cati and Toxascara leonina?
cervical alae is lanceolate in Toxascaris and arrow headed shaped in T. cati
What is the largest intestinal parasite of cattle?
Neoascaris vitulorum
What is the description of the eggs of Neoascaris vitulorum?
subglobular eggs with a thick, pitted, albuminous layer
What is the treatment of ascarid infection in swine?
levamisole, tetramisole, Piperazine
What is the treatment of ascarid infection in dogs and cats?
piperazine, mebendazole, pyranted pamoate
Which species cause milk spots in the liver of affected animals?
Ascaris suis
What is the treatment of ascarid infection in cattle?
piperazine, levamizole, fenbendazole
Which species is associated with a rat-tailed appearance?
oxyuris equi
What condition is manifested as pot belly in dogs?
Toxocara canis
What is the morphology of eggs of Oxyuris equi?
elongate, flattened on one side, with plug on one pole
What are the drugs for Oxyuris equi treatment?
Mebendazole, thiabendazole, cambendazole, pyrantel
What is the esophagus structure of oxyuris equi?
well developed posterior bulb
What is the esophagus structure of Enterobius vermicularis?
double bulb esophagus
What is the SN of the small pinworm of horses?
Probstmayria vivipara
Which pinworm is present in the cecum and colon of rabbits and hares?
Passalurus ambiguus
What are the characteristics of Neoascaris vitulorum?
thick, pinkish when fresh, and cuticle is transparent
Which pinworm is present in the cecum and colon of domestic and wild ruminants?
Skrjabinema spp
What is unique about the small pinworm of horses?
female viviparous and give birth to larvae almost as large as the adult
What does Oxyuris equi produce in the perineal skin?
greyish yellow masses of eggs
they inhibit hormonal synthesis of the parathyroid gland and may result to rachitis
Toxocarids of dogs and cats
during diagnosis, their eggshells are found to have coarse mamillations
Toxocara vitulorum
during fecal examinations, their eggshells have pitted surfaces
Ascaris suis (A. suum)
Toxocara spp found in domestic cats (in the absence of T. cati)
Toxocara malayasiensis
Toxocara spp found in fruit bats that was implicated in an outbreak of hepatitis associated with contaminated fruits in Australia
Toxocara pteropodis
Drugs not recommended for treatment of Oxyuris equi infections
piperazine salt
In diagnosis, the presence of grayish yellow, gelatinous or dried up scale like masses in the perianal region reflect what type of helminth infection?
Oxyuris equi
Human pinworm may also be found in these spp
chimpanzee, gibbon, marmoset
known as the herringworm
Anisakis simplex
known as sealworm that infects cod fish
Pseudoterranova decipiens
Anisakidae spp found in the intestines of fish-eating birds
Contraceacum
Anisakidae spp found in the intestines of predaceous fishes
Hysterothylacium
Rhabditida spp found in SI of moles more common in Australasian marsupials, also a good organism for studies on longevity and parasitism
Parastrongyloides trichosuri
may cause butyric or acetone like odor due to their metabolic wastes
Toxocara vitulorum