NEMATODES: Oxyuriodea spp. Flashcards
What is the common name for Oxyuris equi?
Large pinworm
What type of life cycle does Oxyuris equi have?
Direct
Who are the hosts for Oxyuris equi?
All equids
What distinguishing characteristic can be used to differentiate Oxyuris equi infections from Trichuris spp. or Capillaria (Eucoleus) spp. infections in equids?
Oxyuris equi has only a single operculum, while Trichuris and Capillaria (Eucoleus) spp. have two polar plugs
What gender of adults will be seen in Oxyuris equi infections in equids? Why?
Females, as they emerge out the anus to lay their eggs
What is predliction site for Oxyuris equi?
Dorsal colon
What is laid with the eggs of Oxyuris equi?
A gelatinous substance that is an irritant
What pathogenesis is associated with Oxyuris equi infections?
- Pruritis
- Peri-anal irritation
- Broken hair/ areas of no hair
What diagnostic method is needed for Oxyuris equi infections?
Tape method, or perianal scrapings
Why is reinfection quite common with Oxyuris equi infections?
They will display behaviors associated with rubbing irritated areas against foreign objects, etc. which can further contaminate areas
What pinworm is associated with people, especially young children as a result of poor hygiene, etc.?
Enterobius vermicularis
When is Enterobius vermicularis active?
At night
A member of Filaroidea, Dirofilaria immits will have what type of life cycle?
Indirect
Who are the final hosts of Dirofilaria immitis?
Dogs, cats, and other mammals
True or False: Members of the super family Filaroidea will inhabit the small intestine, and other areas along the alimentary canal.
False, they are unique in that they do not inhabit the alimentary canal
Is Dirofilaria immitis zoonotic?
Yes
Who is the IH for Dirofilaria immitis?
Mosquitoes
What can be seen in a blood smear for dogs infected with D. immitis?
Microfilaria (L1’s)
What technique is often used for microfilaria infections?
Modified Knot’s Technique
True or False: Microfilariae are at an earlier developmental stage than first-stage larvae, and do not contain a digestive tract.
True
True or False: The mosquito, which serves as an intermediate host for D. immitis, can support multiple stages of D. immitis (L1 to L3) at one time.
True
How long can it take for D. immitis L3’s to molt into L4’s?
2 - 3 days
How long does it take for L4’s to molt into Immature adults of D. immitis?
2 - 3 months
Where do Dirofilaria immitis L4’s migrate to once in the host?
They travel within the SQ tissues of the thorax and abdomen
Where do D. immitis L4’s mature into adults?
In the heart, as they get lodged into the distal part of the pulmonary aa.
As a result of increased burdens of D. immitis, where can they also be located, aside from the pulmonary aa.?
Right ventricle and atria, and vena cava
What pathogenesis is assocaited with heartworms?
- Endothelium is destroyed
- Fluid leakage
- Thrombus
- Tortuous arteries
- Increased resistance
- Post-caval syndrome
What bacterium is associated with D. immitis?
Wolbacchia spp.
As Wolbacchia spp. are needed for the overal function of D. immitis, what antibiotic can be administed to treat against Wolbacchia spp.?
Doxycycline
True or False: Severity of clinical disease is not determined by pulmonary blood flow.
False, it is
What common signalment is associated with Dirofilaria immitis?
Large breeds, Males, Over 6 months of age
While ________ tests can be used to confirm infection of D. immitis, though it requires at least 3 sexually mature females present in the host, a ______ ______ can be use as well to identify any mirofilariae.
Antigen
Blood smear
What are occult infections?
Adult parasites are present, but there are no seen eggs or young larvae present
True or False: Adult dogs should be tested for D. immitis prior to beginning prevention.
True
Monthly preventatives are directed and used for the elimination of what stages of Dirofilaria immitis?
L3 and early L4’s
While feline infections are uncommon, why are they more fatal?
- High risk of complications
- Stronger immune response to infections
- Infections occur in the lungs, rather than in the aa.
- No approved treatment
What type of life cycle is associated with Acanthocheilonema reconditum?
Indirect life cycle
What IH’s are associated with the life cycle of Acanthochelionema reconditum?
Fleas, ticks, and lice
Where are adult Acanthocheilonema reconditum found? Where are the microfilariae?
Adult: Subcutis
Microfilariae: Blood
The end of A. reconditum or D. immitis is blunter than the other?
A. reconditum has a blunter anterior end than that of D. immitis
Setaria equina has what type of life cycle? Is there an IH?
Indirect life cycle
IH: mosquito
Where will adult Setaria equini be found in equids? Microfilariae?
Adult: Peritoneal cavity
Mff: Blood
Onchocerca cervicalis is associated with what disease in people?
River blindness
What IH is required for Onchocerca cervicalis?
Cuilcoides spp. aka Biting midges
What is the predilection site for Onchocerca cervicalis?
Adults: CT
Microfilariae: Tissue spaces of skins
What diagnostic test is associated with Onchocerca cervicalis?
As a result of skin infections, a skin biopsy can be used for diagnosis
