This is a small nematode that produces infection in dogs, cats and man
Type of stool:
When fully matured is found in the anterior half of the small intestine
They produce bright red diarrhea due to speed of evacuation of the bowels during diarrhea.
List another parasite that causes this
Strongyloides tumefaciens & S. stercoralis produce many mucosal nodules and the pit in each nodule is visible close up.
Micronema sp. are common horse parasites that invade the CNS. Slide shows adults and developing larvae in the perivascular space of the equine brain.
Esophagus of a rhabitoid nematode in a Micronema sp.
Strongylus sp. feeding on large intestinal mucosa
Small Strongylus worms on the rectal glove of a diarrheic 3 yr old
Lesions in the cranial mesenteric artery caused by migrating Strongylus vulgaris larvae
Strongylus asini an African species infecting zebras. This slide shows the lateral view of the anterior end - notice the mouth
Strongylus asini with numerous nodules filled with parasites in an infected zebra liver.
Syngamus trachea - (trachea worms) occluding the lumen in a pheasants trachea
Syngamus trachea - Section of the trachea with parasites in the lumen and attached to the mucosa
Stephanurus dentatusCommon kidney worm of pigs
Inhibits liver, lungs, spleen, muscles and spinal body cavities.
A single Stephanurus dentatus in the urethra.
Stephanurus dentatus adults in the perineal fat.
What is the 1st & 2nd most common parasite in pigs? How is the parasite passed?
Sheep nodular worm
Common intestinal nematode of farm animals especially sheep and goats.
Name 3 parasites of the intestine that results in the above
Oesophagostomum columbianum as well as Oesophagostomum radiatum, dentatum etc will enter the large intestine and penetrate the intestinal wall and cause inflammation and produce nodular formation.
Type of life cycle
Large-mouthed bowel worm
12 mm in length
Direct life cycle
Migration of Chabertia ovina Signs and Symptoms
The larvae penetrate the mucosa of the small intestine shortly after ingestion and later emerge and pass to the colon.
Cause severe damage to the colon with resulting congestion, ulceration and microhemorrhages (petechial hemorrhages) Infected sheep are unthrifty, feces soft, contain much mucus and may be streaked with blood. Quick immunity develops with these worms.
Ancylostoma caninum - eggs are passed in feces and infected larvae develop in the moist soil and are later ingested.
Hemorrhagic foci in the intestinal mucosa of a Coonhound caused by Ancylostoma caninum
Capsule of Ancylostoma caninum attched to canine intestine in histologic section.
Haemonchus contortus worms present in a sheep abomasum.
Twisted stomach worm of the abomasum in sheep, cattle, goats and other ruminants
Brown stomach worm of ruminants
Dwells in the abomasum and intestines.
Slide shows bovine stomach lining with worms and cysts visible
Characteristic "leather" texture of massive, coalescent Ostertagia ostertagi infection.
Nematodes of the genus Cooperiodes (Cooperia) are small reddish worms found in the small intestine, liver and other viscera of ruminants especially cattle.
This slide depicts sections of a bovine liver with greatly dilated bile ducts and worms present in the lumens of both ducts.
The genus Trichostrongylus is comprised of apx. ____ species. 2 from _______ and the rest chiefly from ___________. Their life cycle and egg development is similar to hookworms
_____________ lives in the abomasum of domestic and wild ruminants and in the GI systems of horses. It is one parasite common to the ruminant and horse.
Trichostyongylus also parasitizes man and has a somewhat high incident in the Orient. Severe diarrhea in an infected sheep pictured here.
Hyostrongylus rubidusRed stomach worm of swine - found worldwide - usually occurs in pigs
Found in soil environments and on grass
Dictyocaulus viviparous is the lungworm of cattle, moose, elk, bison, deer, pigs and other large mammals
Dictyocaulus viviparous - lungworms
Diaphragmatic lobes infected with Pneumostrongylus
Most Metastrongyles are called "______" and inhabit the ___________________ systems of ___________________________. Some of the more common genera are ___________.
respiratory and/or circulatory
carnivores, rodents, primates and swine.
Aelurostrongylus, Pneumostrongylus and Metastrongylus
Metastrongylus - infected lung in which the tip is completely replaced by granulomatous infiltrate.
Cystocaulus infection - the lung is almost completely replaced by developmental stages.
Metastrongylus worms surrounded by fibrotic tissue.
Lesions of Protostrongylus verminous pneumonia in the lungs of Bighorn sheep
Angiostrongylus cantonesis - common parasite of the pulmonary artery of rats in SE Asia and the South Pacific.
Slide shows rat lungs from 50 day old infection with 30 larvae present.
Toxocara canis in an open dog bowel
Toxocara canis - adults emerging from a cut made in a puppy small bowel movement at necropsy (primary method of diagnosis).
Left= Toxocara canis Right= Toxascaris leonina
__________ eggs are colorless with smooth shell and visible vitelline (outside covering) membranes
_________are light brown with thicker, rougher coats and less prominent membranes.