Nematodes Review Exam 2 Flashcards
Direct Smear
mix with saline
40x
trophozoites and motile bacteria
Passive/Standard Flotation
sodium nitrate=fecasol
10 minutes
ova
10x
Centrifugal flotation
1g feces with sodium nitrate
centrifuge 3-6 minutes, 1-2000 rpm
reverse meniscus
wait 10 minutes
fecal sedimentation
ova too large for standard flotation
fluke eggs do not float
cellophane tape test
pinworms (oxyuroidea) and tapeworm proglottids
water/mineral oil
10x
ova
Baerman
warm water/saline
10 hours
larvae
misc. fecal test
fecal occult blood-minor bleeding from parasites
vomitus can also aid in diagnosis of parasites
fecal culture
parasites mature into adult/larvae
modified mcmasters
estimate number of oocysts per gram of feces
used in large animals and adapted from human hookworms
staining fecal slides
direct smear=new methylene blue and Lugoi iodine
trophozoites=diff quick or Wright or Geimsa
Acid-fasting=ID Cryptosporidium sp. with Diff Quick
Blood samples
Hemoprotozoa
Heartworm
Subcutaneous worm
ELISA, IFA, PCR Testing – if sending out, make sure you use the correct tube
Thick or thin smears prepared as is for WBC differential counts
Thin – protozoan and rickettsial parasites
Thick – if low parasitemia
Buffy coat smear
concentration technique for protozoal and rickettsiae in WBCs
direct drop
drop of blood from LTT
microfilariae
Filter test
concentrate microfilaria in blood
Modified Knott’s Test
dilute formalin 2%
ID microfilariae
Dirofilaria immitis vs. Acantheocheilonema reconditum
Antigen test
look for present infection
current infections only
monoclonal antibodies
Antibody test
host immune response
current and prior infections
test contains antigen
symbiosis
Predator-prey (short-lived)
· Phoresis (to carry)
· Mutualism (both benefit)
· Commensalism (one benefits, the other is not harmed and does not benefit- “hitchhiker”)
· Parasitism – one is metabolically dependent and may harm the host
Hosts:
Definitive Intermediate host Paratenic host (transport host) Reservoir host Dead-end host
transmission routes
ingestion: fecal-oral or intermediate/paratenic host
vector
transdermal, transplacental, transmammary
location in host
predilection site
abberant or erratic parasite (heartworm)
female parasites
Oviparous – eggs with single-cell or morula
Ovoviviparous – eggs with 1st stage larva
Larviparous – eggs are retained, birth live larvae
parasite life cycle
Egg (eventually molts – emerges from the egg)
· Four larval stages (wormlike) Infective 3rd stage larva
· Sexually mature adult (predilection site within the definitive host)
· Egg containing a larva, free-living larva, or larva within an intermediate host
Roundworms/Ascaroidea
small inestine
fecal float
eggs round with thick shell
Trichostrongyloidea
trichostrongyle type ova in ruminants
abomasum, small and large inestine
diarrhea, anemia, hypoalbuminemia, “bottle jaw”, reduced growth, death
Rhabiditoidea/threadworms
only a partheogenic female is parasitic
small intestine
diarrhea
Baerman or fecal culture
Trichuroidea/whipworms and capillarids
lemon shaped bi polar plugs
may be misdiagnosed
Oxyuroidea/pinworms
cecum/colon/rectum
cellophane tape test
ova are oval
Spiruoidea
varies
Filaroidea
Dirofilaria immitis-adult female give birth to live microfillarae
