Internal Parasites

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Common and/or scientific names of parasitism
and parasite
Usual location and
gross length
Intermediate
hosts or
direct cycle
Mode of
infection
Treatment* 

Ascariasis

Ascaris suum

Small intestine, bile ducts, stomach
15-30 cm
Direct Orally from contaminated
environment
All

Coccidiosis

Isospora suis

Smll intestine Direct Orally from contaminated
environment
None

Eperythrozoonosis

Mycoplasma suis

On erythrocytes
0.8-1.0 μm
Intermediate hosts. Possible direct Arthropod bites?
Contaminated instruments?
Tetracyclines
Arsenicals

Kidney worm infection

Stephanurus dentatus

Adults in perirenal fat, kidneys, ureters walls. Juveniles in ectopic sites. 20-45mm Earthworms.
Also direct
Larvae in earthworms. Prenatally, orally; skin penetration by juveniles FBZ, AVE, LVM

Lungworm infection

Metastrongylus spp.

Posterior border of diaphragmatic lobes of lungs. 20-50 mm Earthworms.
Also direct
Ingest larvae or earthworms with encysted larvae. DCV, FBZ, AVE

Thorny-headed worm infection

Macracanthorhynchus hirudinaceus

Small intestine, usually ileum
Up to 30 cm
Direct Prenatally, transcolostrally, orally, cutaneously None

Threadworm infection

Strongyloides ransomi

Small intestine of suckling pigs
3.3 -4.5 mm
Direct Prenatally, transcolostrally, orally, cutaneously DCV, FBZ,
AVE, LVM, TBZ

Whipworm infection

Trichuris suis

Cecum and large intestine
5-8 cm
Direct Ingestion of
embryonated ova
DCV, FBZ

Gullet worm

Gongylonema pulchrum

Subepithelium of esophagus, tongue Dung beetles Ingestion of beetle with encysted larvae FBZ, AVE, LVM

Red stomach worm

Hyostrongylus rubidus

Stomach < 10 mm Direct Ingestion of larvae DCV, FBZ,
AVE, TBZ

Thick stomach worms

Ascarops strongylinaand Physocephalus sexalatus

Stomach Dung beetles Ingestion of beetles with encysted larvae FBZ, DCV

Hookworm

Globocephalus
urosubulatus

Small intestine of feral and pastured swine in southern US Direct Larvae bore into skin DCV, FBZ, AVE, LVM

Liver flukes

Fasciola hepatica

Liver of pigs on pastures used by sheep. 30 mm Snails Ingestion of encysted metacercariae on grass None

Trichinosis

Trichinella spiralis

Muscle of many mammals, especially swine and bears Many mammals Ingestion of muscle with encysted larvae (raw garbage, wild animal carcasses, rats, mice, cats) or cannibalism Not practical

Pork measles

Taenia solium
(a tapeworm of man)

Cysticercus cellulosae in skeletal and cardiac muscles of swine.
< 18 mm
Swine Ingestion of human feces
containing gravid proglottids
None

Key:
AVE = avermectin
DCV = dichlorvos
FBZ = fenbendazole
LVM = levamisole
PIP = piperazine
PRT = pyrantel tartrate
TBZ = thiabendazole