Nematodes PpT Flashcards
Adults in SI of pig, rat,
domestic & wild carnivores
and man
Trichinella spiralis
Larva is found in muscles
* Same host serves both as
definitive/final and
intermediate host
No free-living stage (larva
and adult are parasitic
Trichinella spiralis
World’s largest intracellular
parasite
* Causes
Trichinellosis/Trichinosis
No free-living stage (larva
and adult are parasitic
Trichinella spiralis
common name T.spiralis
trichina/muscle/Pig worm
infective first stage larva of Trichinella spiralis in its Nurse
cell in muscle tissue
(Nurse cell-parasite complex)
Affected pig muscles called “
trichinous meat
Diagnosis
Use of-
trichinoscopes
Treatment and Control
Thiabendazole
Trichuridae common name:
“whipworms”
Whipworm species MAN
Trichuris Trichiura
Third most common round
worm of humans
* Found in cecum and colon
one of the “big 4” intestinal
parasites of dog
Trichuridae
Whipworm species pig:
Trichuris suis
Whipworm species GOAT
Trichuris ovis
Whipworm species DOG
Trichuris vulpis
Whipworm species MOUSE
Trichuris muris
Whipworm species CAT
Trichuris campanula
Whipworm species CATTLE:
Trichuris discolor/globulosa
Spear-like projection at the anterior
end for anchorage; feed by means of
their oral stylets
* The egg is lemon or barrel-shaped
* direct life cycle with very resistant
infective egg
TRICHURIAE
Pathogenesis TRICHURIDAE
- loss of weight due to profuse diarrhea
- anemia
- blood-tinged feces
Capillaria (Hairworms)
SITE : BLADDER of dog
Capillaria/
Pearsonema plica
Capillaria (Hairworms)
site Intestinal tract og birds, man
Capillaria/
Aonchotheca
philippinensis
Capillaria (Hairworms)
site Liver of rodents
Capillaria/
Calodium hepatica
Capillaria (Hairworms)
SITE Airways of fox
Eucoleus aerophils
Capillaria (Hairworms)
site Small intestine of birds
Capillaria
caudinflata
Capillaria (Hairworms)
Site crop of birds (I.H earworms)
Capillaria/
annulata
Capillaria (hairworm) Small intestine Birds (I.H.
earthworm)
Capillaria
obsignata/
columbae
capillaria (hairworm)
site esophagus Turkey
Capillaria contorta
Capillaria (Hairworms)
SITE abomasum ruminants
Capillaria bilobata
Male has an ensheathed spicule
* Female bears a protrusible vulva
* Egg is colorless, more barrel-shaped and
polar plug do not project as far
Capillaria sp.
Low grade infections produce cough, wheezy respiration,
weakness, and poor growth
* bronchopneumonia may lead to death
Nasal/Bronchial capillariosis
dysphagia due to inflammation and sloughing off of upper
GIT
Upper digestive tract capillariosis
- First generation adult females are larviparous; Second
generation lay eggs
-severe malabsorption syndrome(protein-losing
enteropathies
Intestinal capillariosis
- First reported in Ilocos Norte 1960’s
- Gastrointestinal enteritis outbreaks and death cases
attributed to Capillaria in Mindanao
Intestinal capillariosis
Dysuria and cystitis
Urinary capillariosis
hepatitis, peritonitis, ascites ( may be fatal
Hepatic capillariosis
one of the largest species of nematodes and considered
as the largest nematode of animals (20-100 cm-female;
14-20 cm - male)
Dioctophyma renale
Dioctophyma renale COMMON name
“giant kidney worm”
SUPERFAMILY
ASCARIDOIDEA
Ascarididae
Oxyuridae
Kathlanida
ASCARIDIDAE genus
Ascaris
Parascaris
Toxocara
Toxascaris
- SI of pig; may crossinfect humans (A.
lumbricoldes) - May grow up to 16 cm
Ascaris suis/suum
Types of life cycle
Tracheal route of migration
* Somatic route of migration
Pneumonia
lung hemorrhage and edema result in
chronic, asthmalike condition
“balling up” cause obstruction, perforation
and peritoniti
Ascaris suis/suum
lipid layer of the
eggshell contains
ascarosides
Ascaris suis/suum
lesion of ascaris suis
“Milk spot lesions
Necrosis and mechanical
obstruction in a child with
A. lumbricoides
Clinical signs
Pot belly
diarrhea
unthriftiness
coughing; “thumps”
jaundice
3 Basic disease problems
common in swine farms
Scouring
pneumonia
parasitism
Adult worms usually cause no symptoms if localised to
the intestinal lumen.
* Infestation may cause impaired growth in children.
Human ascariasis
Larval migration may cause cough, dyspnea, haemoptysis
and eosinophilic pneumonitis
(Löffler’s syndrome)
SI of equine
* tracheal route of migration
* prepatent period almost 3
months
* sub spherical shape egg
Parascaris equorum
white fibrous tracts in the liver
* hemorrhagic pneumonia
* adults may cause impaction and perforation
parascaris equorum
SI of cattle and buffalo
* worm in affected cattle undergoes somatic migration and
mobilized only during pregnancy
* calf infected via milk with L3
Toxocara/Neoascaris vitulorum
Puppies are severely
affected in heavy
infections - potbelly,diarrhea, poor
coa
toxocara/neoascaris vitulorm
- Found in SI of cat
- life cycle like T. canis but prenatal transmission does not
occur - liver fibrosis and lobular pneumonia may occur if tracheal
migration is present
Toxocara cati
Toxocara cati transmmission:
transmammary route
T. cati common name
“Arrow-headed worm of cat”
SI of dog and cat
* transmission is by ingestion of paratenic hosts or by
ingestion of L2
* no migratory cycle takes place
Toxascaris leonina
Visceral Larva Migrans
Condition in man associated with some
nematode species
(T canis, T leonina, T
cati, Bayliscaris procyonis and
Strongyloides ransomi,)
worms migrate aimlessly in the internal
organs of unnatural hosts causing chronic
granulomatous lesions
usually seen in children <4 yrs
may also occur in CNS of pigs
Visceral Larva Migrans
- larva recovered from brain of
parrot with fatal encephalitis
Bayliscaris procyonis
OXYURIDAE
Oxyuris
Enterobius
Oxyuris equi common name:
“horse pinworm”
Sloughing of intestinal mucosa due to feeding by
immature worms but no untoward clinical effects
* anal pruritus due to egg-laying females which result to
“rat-tailed” appearance
“horse pinworm”
Masses of yellowish eggs in
the perineum of horse
“horse pinworm”
Enterobius vermicularis commn name
“human
pinworm or seatworm
Found in the cecum, appendix, and perineal region of
humans and other primates
* more common in temperate countries
Enterobius vermicularis “human
pinworm or seatworm”
Found in the LI of horses
* unusual perpetual parasite
* viviparous female give birth to larvae almost as large as
the adult
* infection is by ingestion of larva through coprophagy
* non-pathogenic
Probstmayria vivipara
SUPERFAMILY
SUBULOROIDEA
FAMILY HETERAKIDAE
Heterakis
Ascaridia
cecum of domestic and wild birds
* transmission is by ingestion of L2 from the soil or by
ingestion of earthworm with L2
Heterakis gallinae
transmits Histomonas meleagridis
Heterakis gallinae
Found in the cecum of pheasants
* typhlitis leads to chronic wasting, emaciation, and deat
Heterakis isolonche
Ascaridia in wild and domestic birds
Ascaridia galli
Ascaridia in pigeon
A. columbae
Ascaridia in turkey
- A. dissimilis
Ascaridia in game birds
A. compar
- Largest and most common nematode of chicken
Ascaridia galli
Superfamily: Rhabditoidea
Family
Strongyloididae
Strongyloides in equine
Strongyloides westeri
Strongyloides in ruminants
S. papillosus
Strongyloides in pigs
S. ransomi
Strongyloides in dogs, cats, man
- S. stercoralis
Strongyloides in cat
S. cati
Strongyloides in birds
S. avium
Modes of transmission Strongyloides spp
Transcolostral part. in swine
* hyperinfection (S. stercoralis)
* autoinfection
* ingestion of infective larva
* skin penetratio
sp. Rhabditiform or filariform esophagus
* viviparous or ovoviviparous female
Strongyloides spp
STRONGYLUS SPP common name
Palisade or “red worms of horses”
STRONGYLIDAE
Strongylus
Oesophagostomum
Chabertia
site Strongylus spp
Found in the cecum and colon of horses
* Well developed buccal capsule, leaf crown, and
copulatory bursa
Ulcers because they are “plug feeders
strongylus spp.
Oesophagostomum sp
“Nodular worm of pigs and ruminants”
Extensive “pimply gut” lesions interfere with absorption
and bowel movement
* Ruptured nodules may cause peritonitis and multiple
organ adhesion
Oesophagostomum sp.
site of adult nodule worm live in the goats and sheep
large and small intestine
CHABERTIA OVINA common name
“Large-mouthed bowel worm”
chabertia - buccal capsule attached to
intestinal mucosa
Chabertia ovina
“Kidney worm of pig”
Found in kidney and perirenal tissue; May migrate
erratically to other organs
* Prevalent in warm and tropical regions
Stephanurus dentatus
Family: STEPHANURIDAE
genus Stephanurus
Infection by
* ingestion of L3
* ingestion of earthworm (paratenic host) which have accumulated
larvae
Stephanurus dentatus
Morphology
* Cup shaped buccal capsule
* Has epaulletes
* Large, stout worm
* Pinkish in color when fresh
Stephanurus dentatus
Also known as the “gapeworm of poultry”
* Found in the trachea of non- aquatic birds
Syngamus trachea
May cause ecchymotic hemorrhages and pneumonia
during migration
* occludes air passages which lead to difficulty in breathing
(gaping movements
syngamus trachea