Parasitology nematodes -Trichostrongyloidea - Ruminants, Rhabditoidea (intestinal threadworms), Metastrongyloidea (lung worms).

What are Trichostrongyles?

These are all nematodes found MAINLY in grazing ruminants, but swine, horses, cats, and birds also host important species. All species in ruminants, except Dictyocaulus (lung), are located in the abomasum and small intestines. Although Trichostrongylus infections are often asymptomatic, large numbers of the parasite (10,000-100,000 or more) can cause debilitating watery diarrhea, especially in stressed or malnourished sheep, cattle, and goats.

Common trichostrongyles

 Haemonchus

Oesophagostomum dentatum (pigs)
 Ostertagia
 Cooperia
 Chabertia
 Trichostrongylus
 Hyostrongylus
 Marshallagia
 Nematodirus
 Dictycaulus
 Bunostomum

…? Im confused. Somethign with ifentifying?

Bovine trichostrongyles
 Identification by fecal culture and larval identification
– ova all look very similar! (With Nematodirus /
Marshallagia as exceptions)

Haemonchus contortus

Barber pole worm of ruminants.
 Gets this name due to the female worm having white, egg filled uterus that spirals around blood-filled gut, giving rise to the so-called “barber pole” effect.
 In heavy infection, the worm can remove up to 1/5 of the circulating blood volume per day from lambs.

What is the Barber Pole worm scientific name?

Haemonchus contortus

Ostertagia ostertagia-

The most important helminth parasite of cattle in the USA. Young cattle infected with large numbers of this parasite waste away and die in a matter of weeks. Those with sub lethal worm burdens tend to have poor growth and development.

 This worm, which resides in the abomasums, causes profuse diarrhea, anemia, hypoproteinemia, and causes malfunction of the abomasum. An animal can literally starve to death, even if it has a full rumen, reticulum, and omasum.

What is the most important helminth parasite of cattle in the USA?

Ostertagia ostertagia-

Ollulanus tricuspis

The feline trichostrongyle
 Vomiting in cats
 Mostly identified by examination of vomitus with a dissecting microscope.
 Diagnosed in chronic vomiting cats by examination of the vomitus, or flotation of the vomitus
 Female has 3 caudal cusps

What is the trichostrongyle of cats?

Ollulanus tricuspis

Do you ever see Ollulanus tricuspis coming from the cat on a slide?

No you will only see a larvae not an egg.

What are the intestional threadworms?

(Rhabditoidea) Strongyloides spp

Rhabditoidea The intestional threadworm.

Strongyloides spp.
 Intestinal threadworms
 Only a parthenogenetic female is parasitic
 No parasitic males
 Larvae have a club-shaped esophagus
 Rhabditiform
 Fresh fecal flotation diagnosis differentiate from
hookworms!

What are the threadworms I need to know? (Rhabditoidea)

Strongyloides sterocoralis, S. tumiefaciens (dog & cat) S. westerni (horses), S. ransomi (pigs), S.papillosus (ruminants)

What is the major route of transmission for Intestional Threadworms?

Major route of transmission is via Trans-mammary from mom to offspring!
• Be aware that direct (oral), cutaneous penetration as well as trans-mammary are all possible routes.

Lung worms? Metastrongyloidea.

Lungworm of swine

What do I need to know about worms?

Name, what animal it affects, where they affect…

How do we diagnose lung worms?

Tracheal wash, Bearman technique?

What are the stomach worms of dogs and cats?

Physaloptera spp.

What is the esophageal worm of dogs

Spirocera lupi

What do Spirocera lupi (esophageal worm) eggs look like?

Eggs have been described as having a paper clip appearance to it.

Idk….

Aonchothea putorii and Ollulanus tricuspis* are also gastric parasites of cats
* See trichostrongyles earlier in presentation!

What are the stomach worms of horses?

Spiruroidea…? Habronema sp. and Draschia megastoma

Stomach worm (Spiruroidea) of horses facts

Habronema sp. and Draschia
megastoma
 Parasite of horses
 Found in the stomach
 Larvae may parasitize skin
lesions or summer sores
 Spread by flies – larvae
migrate in wounds

What are some minor stomach worms?

Gongylonema pulchrum – esophageal worm of ruminants with Dung beetle or cockroach as IH.
 Trichostrongylus axei also stomach worm of horses, pigs and ruminants, but fits in the trichostrongyle group.
 Hyostrongylus rubidus – red stomach worm of pigs
 Ascarops strongylina and Physocephalus sexalatus – also of pigs, require a beetle IH