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438 Cards in this Set
- Front
- Back
Helminths come two types:
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Platyhelminthes (flatworms - flukes and tapeworms)
Nemathelminthes ( roundworms- nematodea and nematomorpha) |
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The third group of helminths is
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Ancanthocephala (thorny head) and has characteristics in common with both groups
|
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All helminths reproduce
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sexually, but some have parthenogenetically produced offspring
|
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Parthenogenetically produced offspring means
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female can reproduce without gamete from male
|
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Oviparous
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female worm produces eggs that are expelled from the host
|
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Ovoviviparous
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larvae are produced by the female
|
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Helminth eggs may hatch
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in the intestine of the definitive or intermediate host, or in the environment
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3 Helminth Classes of veterinary and medical importance
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Platyhelminthes, Acanthocephala
Nemathelminthes |
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Platyhelminthes Class includes
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Trematoda
Cestoda |
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Acanthocephala Class includes
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Acanthocephala - Thorny head worm
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Nemathelminthes Infraphylum includes
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Nematoda - round worms
Nematodomorpha |
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Phylum ???
Class ???? Superfamily ???? includes hair worms or horse-hair worms |
Nemathelminthes
Nematomorpha Gordiodea |
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Superfamily Gordioidea characteristics
|
adults free living in water
cylindrical, long yellow gray to black may have stripes adults do not feed dioecious |
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Gordioidea parasitic form is
|
larvae in insects,
|
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Gordioidea adults
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do not feed
escapte hosts when in water, |
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Dogs and cats may _______
Gordioidea |
vomit up
|
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Nematomorpha are of no importance in
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vertebrates
|
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Nematoda superfamily, Mermithoidea is
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parasitic in insects
|
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Dioecious
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male and female different
|
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Infraphylum: Nematoda includes
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Roundworms
|
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Infraphylum Nematody characteristics
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Longate cylindrical bodies with no segmentations
Dioecious Complete digestive tract Body cavity Free living feeding on organic debris |
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Some Nematoda are parasitic to
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plants, vertebrates and invertebrates
|
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Nematoda life cycles are
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direct or indirect
|
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Infraphylum nematoda esophagus includes the following types
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rhabiditiform
fliariform club shaped bulbed stichosome |
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Rabditiform
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Anterior and posterior swellings - found in soil and plant nematodes
|
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filariform
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simple tube like structure
|
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club shaped
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baseball bat shape
|
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bulbed
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has prominent bulb at posterior
|
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stichosome
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looks like a column of stacked donuts or lifesavers
|
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Nematoda anus
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female - anus
males - cloaca |
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Nematoda males have
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spicules - chitinous organs of intromission - usually paired
|
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Nematoda male organ of clasping
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Bursa and caudal alae with papilliae
|
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Male Nematoda sperm are
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amoeboid
|
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Female Nematoda organs
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vulva, vagina ovajector, one or more uterine horns, ovary
|
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Female Nematoda vulva may be
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anterior mid body or posterior
|
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Viviparous
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living larvae passed.
|
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Development in nematodes includes what stages
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egg, 4 larval stages and 1 adult
|
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L1 nematode hatches and feeds on
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bacteria in the fecal matter.
|
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L1 nematode molts to L2 and L3 which is the
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infective stage.
|
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Development of L3 nematodes is influenced by
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environmental conditions of temperature and moisture
|
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If an intermediate host is involved with nematode development it is infected by
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ingesting the egg and is the host until development to the L3 level.
|
|
Nematode definitive host is where
|
the nematode reproduces
|
|
Hypobiosis
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the interruption of life cycle within a host
|
|
Molting fluids are
|
antigenic compounds that initiate host immune responses and may stimulate resistance at subsequent challenge
|
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Migrating larvae may be associated with
|
tissue damage particularly if molting occurs within the organ.
|
|
Common migration patterns are
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Local migration
Hepatotracheal migration Lymphatic migration Skin tracheal Somatic Direct tissue migration |
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Local migration
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Larvae may migrate deep into an organ but stay in that organ
|
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Hepatotrachal migration
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Gut to Mesenteric veins, portal vein, liver, hepatic veins, vena cava, right heart, lungs, bronchi, trachea, coughed up, swallwed and return to gut
|
|
Lymphatic tracheal migration
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gut to lymphatics to mesenteric lymph nodes, to lymphatic ducts thoracic duct, vena cava, right heart, bronchi, trachea, coughed up, swallowed and return to gut
|
|
Skin tracheal migration
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skin, capillaries, veins, vena cava, right heart, bronchi, trachea, coughed up, swallowed, gut
|
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Somatic migration
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After lung, to left heart, aorta and then to other tissues
|
|
Types of Somatic migration
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Hepatic aortic
Lymphatic aortic Skin aortic |
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Hepatic aortic migrations
|
intestine, mesenteric veins, liver, vena cava, heart lung, heart aorta tissue
|
|
Direct tissue migration
|
Direct penetration through organs with the migration toward a predilections site
|
|
Each Nematode superfamily has
|
Distinct anatomical characteristics
migration patterns, reproductive products, samie tissues or organs Similar methods of control |
|
Nematode Superfamily Rhabditoidea characteristics
|
Fee living, facultative parasites
only females parasitic Direct life cycle |
|
Direct life cycle
|
larvated eggs, or living larvae are produced
|
|
Rhabditoidea transmission
|
Skin penetration, Ingestion, mucous membrane penetration
Trasmammary transmission |
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Rhabditoidea infective stage
|
L3
|
|
One of the first parasites occurring in young animals
|
Rhabditoidea
|
|
Superfamily Rhabditoidea includes
|
Class Secernentea
Order Rhabditia |
|
Strongyloides stercoralis
|
Intestinal threadworm
|
|
Strongyloides stercoralis reproduces in the
|
small intestinal
|
|
Strongyloides stercoralis infects
|
man, primates and dogs
|
|
Strongyloides have what physical characteristics
|
3 tiny anterior papilae, long filariform esophagus and about a third to half the body length
|
|
Strongyloides L1 larvae are
|
passed in feces, have a short buccal cavity and a rhabditiform type esophagus
|
|
Strongyloides L3 may become
|
parasitic or develp to free living adults in warm moist organic matter
|
|
Strongyloides has what type of migration pattern
|
skin tracheal migration.
|
|
Strongyloides molting occurs in the
|
lung
|
|
Immature Strongyloides adults are
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coughed up, swallowed and mature in the small intestine
|
|
Clinical signs of Strongyloides infection include
|
pulmonary signs, watery diarrhea, abdominal distention and shock
|
|
Resistant host
|
normally functioning immune system, with prior exposure to the parasite undergo skin aortic migration
|
|
Strongyloides transmammary transmission
|
larvae are mobilized an tranferred to nursing offspring during hte first few weeks of lactation
|
|
Larvae aquired via transmammary transmission
|
do not migrate but mature and begin reproduction in the small intestine
|
|
Most strongyloides do not have
|
autoinfeciton becase larvated egss are passed in the feces, not larvae
|
|
Strongyloides is a _________ in the SF ______________ not SF _______
|
genus
Rhabditoidea Strongyloidea |
|
Superfamily Strongyloidea Class ____________ Order ______
|
Secernentea
Strongylida |
|
Superfmaily Strongyloidea characteristics
|
large and small intestines, respiratory tract, or kidney fat
direct life cycle well developed buccal cavity, slub=shaped esophagus Males bursate, |
|
Superfamily Strongyloidea females pass
|
thin=shelled segmented eggs
|
|
SF Strongyloidea, Family Acylostomidae includes
|
hookworms
|
|
Ancylostomidae infects the
|
small inetsine
Anterior dorsal bend of mouth parts Large mouth with teeth Direct life cycle plug or blood feeders |
|
SF Strongyloidea
Family Ancylostomidae Ancylostoma caninum |
Dog hookworm
|
|
Ancylostoma characteristics
|
Voracious blood suckers
Small white worms with a hooked anterior 3 pairs of large teeth Males are bursate Direct life cycle |
|
Ancylostoma eggs are
|
thin shelled and segmented
|
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Ancylostoma infectiion is usually via
|
L3 skin penetration
|
|
Ancylostoma migration patterns include
|
skin tracheal migration for 1st infection
skin aortic for L3 in resistant dogs |
|
Occasionally Ancylostomidae are transmitted via
|
transmammary transmission or transplacental transmission
|
|
L3 aquired via transmammary infection do not
|
migrate, but develop in the mucosa
|
|
Prepatent period for Ancylostoma caninum is
|
2 - 10 weeks
|
|
Hookworms can exsanguinate puppies before
|
there is a patent infection
|
|
Cutaneous larva migrans from _________
|
Ancylostoma caninum
from L3 under skin migrating |
|
Cutaneous larva migrans is usually seen with
|
A. braziliense
|
|
Family Strongylidae characteristics
|
large mouth surround by leaf crown
plug or blood feeders direct life cycle Most infections from ingetions of L3 |
|
Family Storngylidae Cyathostomes
|
blood worms, small storngyles
6 genera |
|
Cyathostome characeteristics
|
Short stout red, tan or white worms
mucosal migration adults have 2 lear crowns along anterior buccla cavity |
|
Cyanthostomes life cycle
|
direct
|
|
Cyathostome females pass
|
segmented eggs in feces
|
|
L3 larvae most up vegetation
|
with moisture.
|
|
Cyathostome pathogenesis
|
Nodules formed by larvae
adults feed on mucosa Blood suckers Colitis perforation of intestine, peritonitis poor doers weight loss |
|
Cyathostome prepatent stage
|
up to 2 years
|
|
Cyathostomioisis syndrome
|
younger horses,
late winter/spring after deworming many larva leaving at once damages mucosa causing diarrhea |
|
Superfamily Trichostrongyloidea has what class and order
|
Class secernentea
Order Strongylida |
|
Trichostrongyloidea worms are commonly called
|
Hairworms
|
|
Most Trichostrongyloidea are found in what organs? but one unique genus found where?
|
stomach or small intestine of grazing animals
trachea and bronchi (not important genera) |
|
Trichostrongylids are what size?
|
Small slender worms
< 4 cm in GI tract up to 8 cm in trachea |
|
Trichostrongylids have a _____ buccal cavity and a ______ shaped esophagus.
|
small or absent buccal cavity
club shaped esophagus |
|
Trichostrongyloidea males have what sexual organs
|
bursa and spicules for intromission
|
|
Trichostrongyloidea females have what sexual organs
|
muscular ovajector, uterus straight or spiraled,
|
|
Trichostrongyloidea reproductive products from GI
|
thin-shelled segemented egg - 80 X 40
|
|
Trichostrongyloidea reproductive products from trachea/bronchi
|
L1 larvae
|
|
Trichostrongyloidea has what life cycle
|
Direct
|
|
Trichostrongyloidea GI migration is
|
local
|
|
What species of Trichostrongyloidea did we study?
|
Haemonchus contortus
|
|
Haemonchus contortus is usually found in what species?
|
small ruminants
|
|
Cattle don't have Haemonchus contortus, but have
|
H. placei
|
|
H. contortus adults are what size?
|
10 - 30 mm in length
|
|
H. contortus is found in what GI organ?
|
Abomasum
|
|
Female H. contortus physical characteristics
|
Blood filled GI tract is entwined by egg filled uterus to give it a candy cane look
prominent vulva flap |
|
H. contortus is a voracious
|
blood sucker
|
|
H. contortus male characteristics
|
Bursate Posterior - 2 lateral and 1 dorsal lobe (off side)
2 spicules with barbed ends |
|
The most economically damaging parasite to small ruminants in warm environments
|
H. contortus
|
|
H contortus infection is confirmed when
|
adults worms are identified
|
|
H, contortus infection is suspected when
|
Trichostrongyle eggs are identified in ruminant with anemia and bottle jaw.
|
|
H. contortus infective stage is
|
L3
|
|
H. contortus survives winters by
|
hypobiosis and early 4th stage larvae in abomasum
|
|
H. contortus prepatent period is
|
15 - 21 days.
|
|
H. contortus L1 and L2s feed on
|
feacl bacteria in dung pellets
|
|
H. contortus L3s feed how
|
Dont feed because in L2 cuticle to protect from desiccation.
|
|
H. contortus L'3s leave fecal material and
|
ascend vegetation where grazing animals eat them.
|
|
H. contortus desheath in the
|
L4 stage
|
|
Superfamily Metastrongyloidea Class? and Order ?
|
Class Secernentea
Order Strongylida |
|
Metastrongyloidea are commonly called
|
Lungworms
|
|
Metastrongyloidea infect what organs
|
Trachea, bronchi, bronchioloes, alveoli, pulmonary arteries and venous sinuses.
|
|
Metastrongyloidea are called lungworms because
|
They leave their reproductive elements there.
|
|
Metastrongyloidea pass what type of egg
|
larvated but they hatch so L1 are passed in the feces
|
|
Parelaphostrongylus tenuis infect what organs?
|
Meninges or brain worm of white tailed deer
|
|
Adult Parelaphostrongylus tenuis live in the
|
venous sinuses of meninges and cranial subdural space
|
|
How do Parelaphostrongylus get to the lungs
|
flow passively from the venous sinuses of meninges
|
|
L3 larvae have what migration through the spinal cord
|
direct migration
|
|
Parelaphostrongylus causes what disease to host? and what disease to its neighbors?
|
Very little disease in deer
Devastating disease in abnormal hosts |
|
In abnormal hosts Parelaphostronglus tenuis causes what symptoms
|
nervous signs such as weakness and ataxia to blindness, paresis, paraplegia and death.
|
|
Female Parelaphostrongylus tenuis produce eggs that
|
hatch in the host
|
|
Parelaphostrongylus L1 have what characteristics
|
dorsal pine on tail
348 um long |
|
P. tenuis has what life cycle?
|
Indirect
|
|
P. tenuis direct host is
|
white tailed deer
|
|
P tenuis indirect host is
|
terrrestrial gastropods (snails and slugs)
|
|
Describe P. tenuis life cycle
|
Females lay eggs in venous sinuses, carried to the lungs, entrapped in granulomas, coughed up, swallowed and passed in the feces, L1 penetrate gastropod, eaten by deer, direct migration to spinal cord
|
|
The migration of P. tenuis in indirect species causes
|
inflammatory response in the CNS.
|
|
Superfamily Ascaroidea Class? Order?
|
Secernentea
Ascaridida |
|
Superfamily Ascaroidea has what characteristics
|
Large robust worms
Three large prominent lips Bulb or club shaped esophagus |
|
Superfamily Ascaroidea have what life cycle
|
Direct life cycle
|
|
SF Ascaroida have what type of migration
|
hepato-tracheal migration
|
|
Most common veterinary hosts have
|
acarids
|
|
Ascarids may have
|
paratenic hosts involved
|
|
Paratenic host
|
harbors non-infective forms of parasites
|
|
Ascaroidea Male characteristics
|
small caudal alae with papillae
May have sucker in prenanal area 2 similar spiculs ventrally curved tail |
|
Ascaroidea Female characteristics
|
Larger than males
Very fecund tapered tail, anus near tip |
|
Ascaroidea Female eggs
|
Thick shelled single celled eggs passed in feces
Shell may be rough or smooth |
|
Development of Ascaroidea egg to infective L2 stage occurs in
|
environment, take up to a month
|
|
Once infective Ascaroidea eggs can
|
survive for years in the environment
|
|
Ascarididae family characteristics
|
Infect SI
Direct life cycle Club shaped lips L2 infective stage |
|
Ascarididae has what two genera
|
Ascaris
Toxacara |
|
Ascaris lumbricoides infects what species
|
Man and other primates
|
|
Ascaris lumbricoides characteristics
|
Large stout, cream colored
20 - 40 cm long |
|
Ascaris lumbricoides eggs are
|
oval, single celled, thick brownish yellow mammilated shell, readily float
|
|
Ascaris lumbricoides are not infective until
|
they contain L2 larvae
|
|
Ascaris lumbricoides development in environment takes
|
1 month
|
|
Explain Ascaris lumbricoides life cycle
|
Egg passed in feces, develop to L2 within egg, eggs ingested, hatch in SI, molt to L3 in liver, swallowed, return to SI.
|
|
Ascaris lumbricoides migration
|
Hepatic tracheal
L3 in liver day 4 - 5, lungs by day 10. |
|
Ascaris lumbricoides has prepatent period of
|
2 months
|
|
Ascaris lumbricoides causes what pathology
|
pneumonitis, eosinophilia, weight loss, icterus, allergic reaction, diarrhea, constipation.
|
|
What is the most common parasite of man in the world
|
Ascarid
|
|
Ascaris suum occurs in
|
swine
|
|
Ascaris suum is same as
|
A. lumbricoides
|
|
Toxocara canis is a
|
Ascarid
|
|
T. canis infects what organ
|
SI
|
|
T. canis definitive host is
|
Canids
|
|
T. canis characteristics
|
Adult tan to whitish,
6 - 18 cm in length Stout |
|
T. canis males have
|
narrow finger like appendage on tip
|
|
T. canis egg characteristics
|
round, dark, thick walled with rough outer coat
one of the first in puppies readily float |
|
T. canis has numerous
|
paratenic hosts including man
|
|
T. canis larvae cause
|
most pathology during migration
|
|
T. canis public health importance
|
visceral larva migrans
|
|
T. canis clinical signs in puppies
|
rough hair coat, pot belly, diarrhea, constipation, poor growth rate, obstruction of bile ducts and hollow viscera
|
|
T. canis life cycle
|
single celled egg passed in feces, L2 in month, then ingested by canid.
|
|
The age of the host determines what in T. canis
|
migration pattern
< 5 wks - Hepatic tracheal > 5 wks - Hepatic aortic |
|
T. canis Hepatic tracheal migration
|
Molt to L3 in lung
Molt to L4 and adult in SI 4 - 5 week prepatent period |
|
T. canis Hepatic aortic migration
|
No molting in the lung
L2 goes to somatic tissue |
|
T. canis L2 larvae are mobilized from the somatic tissue
|
35 - 42 days of pregnancy.
cross placenta molt to L2 in fetal liver migrate to lung, SI, eggs passed by pup in 3 weeks |
|
If T. canis L2 ends up in mammary tissue,
|
it travels directly to puppy small intestine with no migration
|
|
Superfamily Oxyuroidea Class? Order?
|
Class Secernentea
Order Oxyuroidea |
|
Enteroibius vermicularis is commonly called
|
Human pinworm, very host specific
|
|
Enterobius vermicularis characteristics
|
slender, cream colored, up to 13 mm with pin like tail
|
|
Most common helminth parasite of humans
|
Enterobius vermicularis
|
|
Enterobius vermicularis females lay eggs
|
at night while host sleeping
|
|
Enterobius vermicularis eggs are
|
oval, larvated, flattened on one side
|
|
Enterobius vermicularis infective stage
|
L3 egg.
|
|
Enterobius vermicularis does not infect
|
dog or cat
|
|
Oxyrus equi
|
Large pinworm of horse
|
|
Oxyuris equi characteristics
|
small mouth, and characteristic esophagus, thick at anterior then narrows
prominent large bulb at end |
|
Oxyuris equi Males
|
rarely seen, blunt posterior, with single spicule
|
|
Oxyuris equi females
|
most commonly seen
long tapering pin like tail |
|
Oxyuris equi eggs have
|
single plug on one end and are slightly flattened.
|
|
Recover Oxyruis equi by
|
using scotch tape near anus
|
|
Oxyruis equi infective stage
|
L3
|
|
Superfamily spiruroidea
Class ?? Order ?? |
Secernentea
Spirurida |
|
Spiruroidea physical characteristics
|
small and slender to short and stout
parasitize stomach or anterior (crop, eye, esophag) 2 or 4 small lips |
|
Spiruroidea has what type of esophagus
|
two part esophagus - muscular anterior, clubbed and glandular posterior
|
|
Spriuroidea has what ____ type of cuticular ornaments
|
bosses, cordons
|
|
Spiroidea females have
|
vulva in esophageal regions, tail tapered with anus near tip
|
|
Spirururoidea males
|
Coiled tail, have caudal alae with papillae, uneaqual and dissimilar spicules
|
|
Spiroidea eggs are
|
thick shelled
small larvated don't float |
|
Spiruroidea have what type of life cycle
|
indirect
Indirect host is arthropod |
|
Infective stage of Spiruroidea is
|
L3
|
|
Spiruroidea spp
|
Physaloptera
|
|
Physaloptera spp infects what species
|
Carnivours mammals, birds, reptiles, common parasite of cats, skunks, occasionally dogs
|
|
Physaloptera is embedded where
|
in stomach wall
|
|
Physaloptera characteristics
|
short stout worms, pair of very small lips
cuticular collar |
|
Physaloptera spp eggs
|
larvated, rarely seen, few in number, do not float - use sedimentation
|
|
Physaloptera spp are usually found during
|
endoscopy or after being vomited up.
|
|
Physaloptera spp larvae in feces
|
L1
|
|
Physaloptera larve are ingested by
|
coprophagia
|
|
Host is infected by Physaloptera by
|
eating the IH, an insect
|
|
Damage by Physaloptera spp worm in stomach is
|
minimal
|
|
Superfamily Filariodea
Class? Order? |
Secernentea
Spirurida |
|
Filarioidea live where
|
outside the alimentary canal - (extra intestinal) in blood vessels, lymphatics, body cavities, ligametns, connective tissue
|
|
Filarioidea reproductive products are found where
|
not in the feces
|
|
Filarioidea direct host
|
mammals, birds
|
|
Filarioidea indirect host
|
hematophagous (blood sucking) insects
|
|
Filarioidea male characteristics
|
corkscrew tail, 2 unequal picules, may have caudal alae
|
|
Filarioidea female characteristics
|
anterior vulva, viviparoud, produces microfilaria
|
|
Filarioidea microfilaria lives in
|
blood, lymph and skin.
|
|
Filarioidea has what life cycle
|
indirect life cycle
|
|
Filarioidea larvae develop from L1 to L3 stage where
|
within the malphigian tubules, throacic muscle, or fat body of the invertebrate indirect host
|
|
Filarioidea infective stage is the
|
L3 stage
|
|
Heart worm is
|
Dirofilaria immitis
|
|
Dirofilaris Immitis adults live where
|
in the right ventricle and pulmonary arteries
|
|
Dirofilaris immitis physical characteristics
|
slightly tapered anterior and straight tail.
|
|
D. immitis development to L3 occurs in the _____ in _____ weeks
|
mosquito
2 weeks |
|
D. immitis L4 larvae
|
begins migrating in the subcuaneous tissue and molts to L5 (adult stage)
|
|
At 3 months post infection, D. immits
|
migrates perivascularly to the right heart and pulmonary arteris.
|
|
The prepatent period is approximately
|
6 months
|
|
In D. immitis problems com from the worm and
|
antigens
|
|
If large numbers of D. immitis larvae enter the heart during a short time frame
|
venacaval syndrome can occur.
|
|
Venacaval syndrome
|
presence of worms and excretory/secretory antigens cause proliferation of pulmonary artery intima, occluding smaller branches
|
|
Diagnosis of heartworms should be done via
|
both finding circulating microfilaria in the blood and/or detecting antigens.
|
|
Drugs that rapidly kill D. immitis larvae are
|
contraindicated because the dog may go into shock.
|
|
Monthly preventative are effective against
|
The L3 and L4 stages.
|
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Superfamily Trichuroidea
Class? Order ? |
Enoplia
Trichocephalida |
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Trichuroidea superfamily has the
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greatest diversity of any superfamily
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Stichocyte is a
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Each cell of an esophagus that is arranged like donuts in a stack,
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Stichosome is
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an esphogus that has cells stacked like a donuts.
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Male Trichuroidea characteristics
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curved posterior end
single spicule surrounded by a protrusable spiny sheath exception = Genus Trichinella |
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Trichuris spp
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whipworm
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Trichuris spp characteristics
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very long slender filiform anterior end containing a stichosome esophagus, short thick posterior end with other organs in posterior
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Trichuris spp adults live in
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cecum
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Trichuris eggs are
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barrel shaped with bipolar plugs and usually borwn or golden
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Trichuris eggs
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float but require sp. gravity of 1.18
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Trichuris males have
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spiral coiled tail in male
single spicule within a spiny sheath |
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Trichuris has what life cycle
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direct.
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Trichuris eggs are passed in the
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feces
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Trichuris infective stage is
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L1
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Trichuris L1 larvae are ingested and
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travel to SI and enter mucosa and molt to L4.
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Trichuris is rarely
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pathogenic - may cause bloody diarrhea
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Trichinella spiralis characteristics
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Slender worm with stichosome esophagus
Male - no spicule Female - viviparous |
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Trichinella spiralis has what life cycle
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direct.
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Trichinella spiralis enters the host by
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the host eating infected striated muscle
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Trichinella L1 larvae are ingested and
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travel to SI and develop to adults.
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Trichinella has what migration
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lymphatic - aortic migration.
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Trichinella is predilected to the
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diaphragm, tongue, masseters, and intercostals
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Human Trichinella disease is characterized by
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intestinal phase, invasion,
encapsulation, and calcification |
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Human Trichinella diease is most often acquired by
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ingestion of raw or insufficiently cooked pork, bear meat, or meat from seals and walrus.
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Phylum Platyhelmintehs includes
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flatworms
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Classes of Platyhelminthes
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Tubellaria - free living
Cestoda - tapeworms Trematoda - flukes |
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Cestoda and Trematoda differ by
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Cestoda - flat segmented
Trematoda - flat, non-segmented |
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Class turbellaria appear to be parasites but
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have toxic dermal slime and are vomited up by cats - so are prey that cats have no use for.
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Class cestoda are
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tapeworms
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Cestoda physical characteristics
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Flatworms with a scolex, suckers or bothria and a strobila with many segments
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Tapeworm segments are called
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Proglottids
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Each proglottid is contains
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one or more sets of reproductive organs
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Cestoda are
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monecious
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Cestoda have
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no body cavity, reproductive organs embedded in parenchyma
no mouth or alimentary tract |
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Cestoda nutrition is
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absorbed through cuticle
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Cestoda suckers are called ? and the elongate slits are called
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acetabulae
bothria |
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Cestoda proglottids are continually
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produced by asexual budding from the anterior
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As cestoda mature either
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gravid proglottids or eggs are expelled from the posterior end of the worm.
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Cyclophyllidae has a
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Scolex with 4 suckers and rostellum.
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Cyclophyllidea rostellum are either
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armed - with hooks
unarmed - without hooks retractable and armed |
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Cyclophyllidea pass what in the feces
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gravid segments, not eggs
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Cyclophyllidea immature segments contain
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developing reproductive organs of both sexes
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A gravid proglottid is
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uterus fills with eggs and the reproductive organs atrophy
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Eggs exit the proglottid via
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a genital pore or segment splits open releasing eggs
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a cyclophyllidae embyrophore contains a
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hexacanth embryo, a larval stage with 6 hooks.
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The embryophore release the hexacanth when
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ingested by an intermediate host
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The hexacanth migrates
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through the intestinal tract of the intermeidate host
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The hexacanth enters the definitive host how
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by ingesting the indirect host.
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Dipylidium caninum
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double pored tapeworm
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Trichuroidea male physical characteristics
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small mouth,
curved posterior end, single spicule with spiny sheath |
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Exception to Trichuroidea male characteristics
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Trichinella has no spicule
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Trichuroidea female physical characteristics
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Bluntly rounded posterior
vulva near base of esophagus eggs with polar plugs |
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Exception to Trichuroidea female characteristics
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Trichinella produces larvae
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Two Tichuroidea genera we studied
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Trichuris
Trichinella |
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Trichuris is otherwise known as
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whipworm
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Trichuris spp characteristics
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Long, slender, filiform anteriorend with stichosome esophagus
Thick posterior end with other organs in posterior |
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Trichuris adults live in the
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cecum or upper colon.
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Trichuris does not occur in the
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horse
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Tricuris eggs
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barrel shaped with bipolar plugs, brown, or golden
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Trichuris male characteristics
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sprial coil with single spicule within a spiny sheath
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Trichuris has what life cycle
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direct
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Trichuris eggs are passed in the
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feces
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Trichuris eggs develop to L1 in
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2 weeks
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Trichuris infective stage is the
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L1,
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The L1 Trichuris egg hatches in the _____ and molts to adult in _____
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Small intestine
3 - 10 days |
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After molting to adult stage, Trichuris moves
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to the lumen of the ceum, threads through the mucosa and feeds on blood.
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Maturation of Trichuris takes
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3 months
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Trichinella spiralis characteristics
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Males no spicule
females viviparous |
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Trichinella have a _____ life cycle
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direct
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Trichinella larvae are found where
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encapsulated in musclature of mammals
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Trichinella L1 larvae migration
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lymphatic - aortic
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Trichinella prefer what muscles
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diaphragm, tongue, masseters, and intercostals.
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Human Trichinella disease has what phases
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Intestinal (adults in SI)
Invasion (female in mucosa) Encapsulation (L1 in muscle) Calcification (of encapsulated L1) 6 months to 1 year) |
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Trichinella can be prevented by
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heating meat to 37 C or 170 F or freezing to 15 C or 5 F for 20 days.
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Phylum Platyhleminthes has what Classes
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Class Cestoda
Class Trematoda and Class Turbellaria |
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Class Tubellaria are the
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Free living carnivorous flat worms
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Tubellaria are not parasities ut
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Prey
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Cestoda is also called
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Tapeworms
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Cestoda heads have
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scolex ( head) with suckers
Strobia (body) with many segments |
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Direct host of Dipylidium caninum
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Dogs, cats, and occasionally humans
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Indirect Host of Dipylidium caninum
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flea
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Dipylidium caninum attaches to ____ via
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SI
armed rostellum and suckers |
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Dipylidium caninum rostellum contains
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several rows of small hooks on a protrusive proboscis
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Immature Dipylidium segments are _____ while mature segments are
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wider than long
square or elongate |
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A gravid Dipylidium proglottid resembles
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a cucumber seed
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Each Dipylidium proglottid contain ____ that contain___?
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eggs
hexacanth |
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The larval stage of the Dipylidium is the ?? and it develops in the _____
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cysticercoid
develops in the flea |
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The intermediate host of Dipylidium is infected by
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the larval flea eating the hexacanth embryo of the Dipylidium
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The hexacanth embryo of Dipylidium does what when it enters the flea gut? and becomes?
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tears the digestive tract, with its hooks
cysticercoid |
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A cysticercoid is a
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solid cyst-like structure containing a protoscolex of Dipylidium
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After ingestion by the DH , the cysteiceroid is ___ and the _____ does what?
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freed and the
protoscolex attaches to the intestinal wall and begins development |
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The prepatent period for Dipylidium is
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2 - 3 weeks
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Gravid Dipylidium eggs have what unique feature
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2 pores.
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The beef tapeworm
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Taenia saginata
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Taenia saginata adult tapeworm is found where
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SI of direct host
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Taenia saginata scolex has
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4 suckers and is unarmed
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What is the unique feature of Taenia saginata compared to other Taenia
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Unarmed
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Progolttids of Taenia have what features
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Single lateral pore
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mature Taenia proglottids have how may reproductive organs?
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1 set
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Gravid Taenia proglottids have what reproductive organs
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egg filled uterus
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Taenia uterus is
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branched.
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Taenia reproduction occurs where
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in DH to produce egg
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Taenia intermediate host is
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Cattle
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Taenia structure found in the IH is
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cysticercus
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Cysticercus is a
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fluid filled sac like structure about the size of a pea with an invaginated protoscolex that develops in the muscle of cattle.
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Taenia saginata definitive host is
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humans.
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Cattle are infected with Taenia by
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ingestion eggs
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After egg ingestion, the Taenia hexacanth embryos _______ and travel to _______ .
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enter the intestinal wall and are carried to capillaries in muscle.
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The predilaction site for Taenia larva in cattle is
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masseter heart, tongue and diaphragm, but all are susceptible.
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A Taenia cysticercus develops where and is infective when
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in the muscle (beef)
10 weeks later. |
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Coenurus is a
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fluid filled cyst with multiple inverted scolicies, mammals
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Hydatid (Ecnhinococcus)
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Thick walled cyst containing multiple scolicies, mammals
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Cysticercoid is a
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solid cyst with single inverted scolex, invertebrate
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Tetrathyridium (mesocestoides) is
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a long flattened larvae, vertebrate
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Taeniads of dogs have what as intermediate host
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rabbits, ruminants, swine,
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Canine and feline Taenia spp have
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armed scolices
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What species is closely related to Taenia that has great public health importance?
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Echinococcus
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Echinococcus granulosus causes
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Hydatid Disease
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Echinococcus granulosus intermediate hosts
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ruminants, swine, marcropods, equids, and humans
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Echinococcus DH is
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canids only
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Echinococcus granulosus Scolex has
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4 suckers, and is an armed rostellum.
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Echinococcus granulosus has what segment characteristics
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single lateral pore and last segment is longer than wide.
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Hydatid cyts is
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fluid filled thick walled opaque systs with germinal membrane
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Brood cysts from hydatid cyst develop
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from germinal membrane and contain numerous scolicies
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Hydatid sand is
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frescolicies in cyst fluid
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Hydatid cysts are usually in
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liver (70%)
lungs (25%) |
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Echinococcus granulosus infection causes what in ruminants
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nothing
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Echinococcus granulosus infects humans when they
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eat the egg, not cysts
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Echinococcus multilocularis has what host cycle
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dog or fox and rodent.
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Echinococcus multilocularis cyst characteristics
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mulitlocular cyst acts like an invading tumor in humans
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Class Trematoda includes
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Flukes
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Trematodes have an
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indirect life cycle
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The intermediate host of trematodes are
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mollusks
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Trematode physical characteristics
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oral and ventral suckers
No body cavity, organs embeddedi n parenchyma mouth and blind alimentary tract - no anus |
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Fluke organs are
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suckers, caeca, testes, ovary, uterus, vitelline glands
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Trematode subclass Digenea has what aspects of life cycle in larvae
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In mollusk they have asexual reproduction
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Trematode Diegenea has what parts of life cycle in DH
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Adults stagei in vertebrates has sexula reproduction
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Digenena attach to host via
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acetabulum ( ventral sucker)
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Digenena have what reproductive states
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monoecious
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Fasciola hepatica is _______ while Fasciola mansoni is _____
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monoescious
dioecous |
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Fasciolidae is typically found in
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bile ducts
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Fasciolidae physical characteristics
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Grayish brown, small pines on cuticle
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Branched organs in Fasciolidae
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caeca, ovary, and testes
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Fasciolidae eggs have
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operculum cap at one end
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Fasciolida DH include
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ruminants, and other species
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Fasciola hepatica ciliated larva are called
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miracidium.
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Miracidium escapes the egg how?
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through the operculum and must find a snail within a few hours
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Lymnaeid snails are
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right handed and have triangular antennae
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What larval form penetrates the snail's foot..
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miracidium
then it loses its cilia and transforms into a sac-like structure, the sporocyst. |
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Within Fasciolidae sporocysts, __ are produced by____.
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redia
asexual reproduction |
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Fasciolidae sporocyts travel to the
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snails heaptopancreas and undergo division
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Fasciolidae sporocyts are produced by
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asexual reproduction within the redia.
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The infective stage of Fasciolidae is the
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cercaria.
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The Fasciolidae ceracria leaves the snail how
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expelled from the snail into water.
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After Fasciolidae cercaria enter the water they
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attach to vegetation. Become infective when vegetation eaten.
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Once ingested, fluke larvae (marita)
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exists the cyst and burrows through the wall of the intestine.
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Flukes have what migration pattern
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direct
go to liver |
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The prepatent period of F. hepatica is
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10 - 12 weeks.
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F. heptatic causes
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secondary bacterial infection, tissue destruction and blood loss.
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What bacteria thrives in liver tissue after F. hepatica migrates through
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Clostridium
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Schitsosomatidae are found where
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veins of mammals and birds
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F. Hepatica has what clinical signs
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anemai, hypoproteinemia, edema and progressive weakness
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Schistomomatidae males are ____ compared to _____.
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more robust
females - long and slender |
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Schistosoma mansoni is found in the
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mesenteric veins
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Schistosoma mansoni DH
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man, primates and rodents
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Schistosoma mansoni reproductive locations and types
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asexual in the snail
sexual in the DH |
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The infective stage of Schistosoma mansoni
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forked tail cercaria by skin penetration
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The female Schistosoma mansoni lays eggs where and then they travel how
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in the mesenteric vein
burrow through the vein wall into lumen of GI tract and are excreted in feces. |
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Schistosoma mansoni ___________ infects the snal and produces ________ or ____ prodcucing the _____
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miracidium
2 generations of sporocysts forked tail cercaria - released from snail |
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If Schistosoma mansoni eggs do not travel to gut, they ____
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carried to liver and produce a granuloma that may survive for 30 years
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Bird Schistosoma may infect ___- via ____ entering the ____
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Humans
cercariae skin |
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Heterobilharzia americana is
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uncommon but not rare parasite of dogs in the gulf coast and central Texas.
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Dogs infected with Heterobilharzia american have what clinical signs
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bloody diarrhea
hypercalcemic |
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Phylum Acanthocephala are also called
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thorny headed worms
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Acanthocephala have
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Pseudosegmented body
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The anterior part of an Acanthocephala worm is called ?? and consists of ?
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Presoma
a retractable proboscis covered with hooks |
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Acanthocephala physical characteristics
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No mouth
No alimentary tract have a body cavity Dioecious |
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Acanthocephala absorb nutrients how
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through cuticle
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Acanthocephala have what life cycle
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indirect life cycle
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Male Acanthocephal characteristics
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protrusable bursa
conical penis |
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Acanthocephala female characteristics
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ovaries, uterus, uterine bell
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Acanthocephala uterin bell does what?
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sorts eggs for expulsion
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Acanthocephala larvae are called?
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acanthor
has small spines on anterior end |
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Macracanthorhynchus hirudinaceus DH
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swine
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Macracanthorhynchus IH
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dung feeding beetles
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Macracanthorhynchus hirudinaceus common name
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thorny headed worm.
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Acanthor eggs pass through beetle gut wall and
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develops to acanthella in haemocoel of insect.
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When mature, the Macracanthorhynchus hirudinaceus larva becomes a
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cystacanth
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A Macracanthorhynchus cystacanth is a
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miniature version of the adult.
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Macracanthorhynchus ingens infects
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racoon, and dog.
dog will vomit it up. |