Nematodes 2

Eggs of Strongyloides westeri, the intestinal threadworm of horses. The 3 larger eggs are those of Strongyles sp. X100

Eggs of Strongyloides westeri, these eggs are embryonated when laid. X400

Eggs of Strongyloides papillosus the "intestinal threadworm" of cattle, sheep, goats, and rabbits. X100

Eggs of Strongyloides papillosus, these eggs are embryonated when laid.

Eggs of Spirocerca lupi, the esophageal worm of dogs and foxes.

Eggs of Spirocerca lupi X400

Large Spirocerca nodules in the lumen of the esophagus. Adult worms are seen here in granulomous lesions.

Sarcoma in the esophagus due to Spirocerca sp.

Opened esophagus of a dog with 3 distinct nodules produced by Spriocerca sp.

• Spirocerca eggs: A. Low power
•                         B. High power

Spirocerca lupi- eggs contain a fully formed larva. They are smallest embryonated ova seen in dog feces.

Egg and larvae of Parasonema plica. This is the parasite of the urinary bladder, but is commonly found in feces.

Parasonema plica eggs X400

Eggs of Dioctophyma renale, the giant worm of dogs, foxes, and occasionally man. These eggs are usually found in urinary sediment. They may be found in feces contaminated with urine.

Eggs of Dioctophyma renale. The shells are thick and rough. The color on a fecal exam is yellowish brown.

Eggs of Stephanurus dentatus, the kidney worm of swine. These eggs are found in the urinary sediment and occasionally in the feces.

Eggs of Stephanurus dentatus X400

Eggs of Physaloptera praeputialis, the stomach worm of cats, dogs, foxes and wild felidae.

Eggs of Physaloptera praeputialis X400

Physaloptera rara (stomach worm) looks like an ascarid except their eggs are smooth and contain an embryo when passed in the feces.

Eggs of Habronema muscae one of the gastric nematodes of horses. These eggs are elongated and embryonated when laid. X400

Eggs of Habronema muscae

Eggs of Draschia megastoma. These eggs are from the exudate in a gastric abscess, which contains adult worms.

Eggs of Draschia megastoma, will be seen as larvae in the feces.

Chronic gastritis in a horse with numerous ulcers associated with Trichostrongylus axei.

Inflammation and catarrhal (pus) in the stomach caused by Trichostrongylus axei.

Gasterophilus intestinalis in the white area of the stomach, and Gasterophilus nasalis in the duodenum.

Submandibular edema "bottle jaw" in the cow with parasitic gastritis.

Eggs from Haemonchus sp. the stomach worm of cattle, goats and sheep.

Eggs of Haemonchus contortus, the "common or twisted" stomach worm of cattle, sheep, goats.

Haemonchus sp worms on the mucosal surface. Notice the female worms resemble a barber pole.

Eggs of Ascarops strongylina another stomach worm of swine.

Large adult Strongyles attached to the mucosa of the ventral colon.

Several species of Strongyles sp. eggs. Forty species of this nematode have been reported form the large intestines of horse, asses, and mules in North America.

Two different Strongyles sp. eggs.

Eggs of Oxyuris equi the "rectal worm of horses". These eggs may be found in the feces, but examination of anal scraping is the more accurate method of diagnosis.

Eggs of Oxyuris equi, note the operculum at one end.

Eggs of Nematodirus spathiger (the largest egg) also called the "thread necked nematode" of cattle, sheep, and goats.

Eggs of Nematodirus spathiger notice the distinctive large cells inside the egg.

Eggs of Oesophagostomum sp. the nodular worm of swine.

Eggs of Oesophagostomum sp.

Eggs of Macracanthorhynchus hirudinaceus, the thorny headed worm of swine.

Eggs of Macracanthorhynchus hirudinaceus, notice the embryo is surrounded by three shells. The outer shell is dark brown.

Eggs of Macracanthorhynchus hirudinaceus Note this is actually a cestode not a nematode.

Dirofilaria immitis larvae (microfilaria). The first stage of Heartworm infection in dogs, foxes, coyotes, wolves and cats.

Dirofilaria immitis larvae in blood

Dirofilaria immitis larvae. The blood hemolyzed in 2% acetic acid (vinegar), this is why the larvae are almost straight.

Dirofilaria immitis larvae in hemolyzed blood.