endoparasites and blood worms

Round worms

Adults reside in the small intestine and may cause vomiting when they swim to the stomach

Direct life cycle

Ascarids

Ascarid

Host species: dog

Size: 75-90 um

Prepared period: 21-35 days

Transmission: ingestion Transplacental trans memory

Toxocara canis

ascarid

Host species: cat

Size: 65-75 um

Prepatent period: 42-56 days

Transmission: ingestion trans mammary

Toxocara cati

Ascarid

Host species: dog and cat

Size: 75-85 um

Prepatent period: 77 days

Transmission: ingestion trans placental

Does not have zoonotic potential

Toxascaris leonina

Ascarid

Host species: raccoon

Zoonotic parasite of significant concern

Larvae migrate to the CNS and produces a condition known as neurological larva migrans

Baylisascaris procyonis

Strongyloidea

Hookworm

Why must you remove feces immediately if you suspect hookworms

Eggs larvae rapidly and fresh feces is required to diagnose

how do hookworms cause damage

They attach to the intestinal lining and feed on blood. Black tarry stool may be evident

Strongyloidea

Southern canine hookworm

Host species: dog

Size: 55-75 um x 27-47 um

Prepatent period: 14-21 days

Transmission: ingestion trans placental percutaneous trans mammary

Anclyostoma caninum

Strongyloidea

Northern canine hookworm

Host species: dog

Size: 63-93 um x 32-55 um

Prepatent period: 14 days

Transmission: ingestion percutaneous

Strongyloidea

Feline hookworm

Host species: cat

Size : 55-75 um x 34.4-44.7 um

Prepatent period: 14-21 days

Transmission: ingestion percutaneous

Ancylostoma tubaeforme

Strongyloidea

Canine and feline hookworm

Host species: dog and cat

Size: 75-95 um x 41-45 um

Prepatent period: 21 days

Transmission: ingestion percutaneous

Anclyostoma braziliense

trichuroidea

Whipworms

How do whipworms cause damage

They reside in the cecum and colog of respective host where they suck blood

Trichurid

Host species: dog

Size: 72-90 um x 32-40 um

Prepatent period: 90 days

Transmission: ingestion

No zoonotic potential

Trichuris vulpis

Respiratory parasites within the trichuroidea family

E. Aerophilus

E. Boehmi

Trichurids - eucoleous

Host species: dog and cat

Size: 58-79 um x 29-40 um

Prepatent period: 42 days

Transmission: ingestion

asymetrical polar plugs

eucloeus aerophilus

Trichurid - eucoleous

Host species: dogs

Size: 54-60 um x 30-35 um

Prepatent period: 42 days

Transmission: ingestion

symmetrical polar plugs

Eucoleus boehmi

Urinary parasites

Indirect life cycle

Pearsonema plica/feliscati

Respiratory parasite

Host species: cat Size

Adults live in respiratory bronchioles and alveolar ducts where they create egg nests. Larvae coughed up and passed in feces

Indirect lifecycle

Metastrongyloidea

Giant kidney worm

Host species: dog

Size: 71-84 um x 46-52 um

Prepatent period: 18 weeks

Transmission: ingestion

Phylum platyhelminthes

Flat worms

Two classes of flatworms

Cestoda and trematoda

Common name for cestoda

Tapeworm

Segments on tapeworms that are shed and contain a single egg of packets of eggs

proglottid

taenia spp

Rice grains - individual ova

Size: 32 - 37 um

Prepatent period - 60 days

Transmission - ingestion

Taeniid tapeworm

Rabbit intermediate host

Host species - dog

Taenia pisiformis

Small rodent intermediate host

Host species - cat

Taenia Taeniaformis

Intermediate host - flea

Host species - dog/cat

Size - 200um/50um - can vary

Prepatent period - 14-21 days

Transmission - ingestion

Dipylidium caninum

Intestinal fluke

Lizard poisoning - cat eats lizard or amphibian

Adult flukes inhabit liver, gallbladder, bile Ducts, and less commonly the small intestine

Platynosomum fastosum

Salmon poisoning fluke of dogs in the Pacific Northwest

Dogs eat infected fish

Adult fluke’s inhabits the small intestine and serves as vector for rickettsial agents

Nanophyetus salmincola

Intestinal flukes of dogs and cats

Found throughout North America

Dog or cat eats an infected frog snake or mouse

Ova are large, golden brown and operculated

Alaria spp

Lung fluke

Host species - dog/cats

Size - 75-118um x 42-67 um Prepatent

Prepatent period - 30-36 days

Transmission - ingestion of infected raw crayfish or crab

Paragonimus keliicotti

True or false

Paragonimus keliicotti can be observed on radiograph due to adult flukes occurring in cystic spaces connected to the terminal bronchioles within the lung parenchyma of dogs and cats

True

Why must certain flotation solutions of special techniques be used to observe Protozoa

Because of their size and fragility

Very small single celled parasites that are often transmitted to host via ingestion of a cyst

Protozoa

Techniques/solution commonly used to look for Protozoa

Direct smear + Legolas iodine

Acid fast staining

Antigen testing

Protozoa common in puppies and kittens

Characterized by diarrhea + lethargy and weight loss

Rarely clinically significant in adult animal

Coccidia - cystoisospora

Direct life cycle with situated form

Prepatent period 7-14 days

Cystoisospora spp

Nematodes affecting horses

Strongyloidea, ascaroidea, rhabditoidea, oxyroidea

Strongyles affecting horses

Strongylus vulgaris, strongylus edentatus, strongylus equinus

Ascarid genus affecting horses

Parascaris equorum

Rhabditoidea genus affecting horses

Strongyloides westeri

Host species horse

Prepatent period 70 days

Measurement 90-100 um

Found in the small intestine of horses - particularly in young foals

Ascarid

Parascaris equorum

Found in the large intestine

Referred to in Terms of “small type” or “large type”

Strongyles

Strongly referred to as the blood worm

Strongly vulgaris

Strongyles that cause liver damage

Edentatus and equinus

Strongyles size variation

70-90 um - 40-50 um

Parthenogenic female parasites - asexually reproducing female parasites affecting horses

Strongyloides westeri

True or false

Strongyloides westeri ova are larvated

True

Strongyloides westeri size and transmission

40-50 um x 32-40 um

Trans mammary and transcutaneous

equine pinworm

oxyuris equi

Where are adult picture equi worms found

cecum, colon, and rectum of horses - may protrude from the anus.

How can oxyuris equi eggs be recovered from the anus

By using cellophane tape or gentle scraping

Host species horse

Size 90 × 40 um

Prepatent period 5 months

Eggs may be larvated

Oxyuris equi

Eucestode genus

Anaplocephala perfoliata, anaplocephala magna, anaplocephala mamillana

Anaplocephala common name

Equine tapeworm

What is the equine tapeworm intermediate host

Grain mite

Host species horse

Size 65-80 um

A. Perfoliata

Host species horse

Size 50-60 um

A. Magna

Host species horse

Size 37-51 um

P. Mamilliana

Apicomplexa common name and genus

Coccidia

Eimeria Leilani

Host species horse

Size 70-90 um

Prepatent period 15-33 days Measurement

Usually found in young animals

Eimeria leuckarti

trichostrongyles genus

Trichostrongyles type

Nematodirus

Marshallagia

Host species ruminants

Regardless of size or species, ova are nearly identical

Trichostrongyles type

Host species ruminants

Size 150-230 um x 80-100 um

Nematodirus app

Host species ruminants

Size 160-200 um x 75-100 um

Marshallagia spp

Eucestode genus in ruminants

Maniezia benedeni

Maniezia expansa

Trematode genus in ruminants

Fasciola hepatica

Paramphistomum

Cotylophoron

Dicrocoellum dendriticum

Host species cattle sheep and goats

Size 56-67 um

Cestode

Moniezia expansa

Host species cattle

Size 75 um

Cestode

Moniezia benedini

parasite that can leave cysticeri is cattle musculature of cattle and can cause beef measles in humans

Taenia saginata

Host species ruminants

Size 130-150 um x 63-90 um

Liver fluke

Fasciola hepatica

Coccidia affecting ruminants

Eimeria spp

Eimeria bovis

Eimeria zuernii

Cryptosporidium

Host species cattle

Size 20 × 28 um

Eimeria bovis

Host species cattle

Size 15-22 um x 13-18 um

Eimeria zuernii

Significant public health concern for humans

Causes frequent mucoid diarrhea

Size 4-6 um

Cryptosporidium

Host species swine

Size 50-80 um x 40-60 um

Damage to liver with larval migration

Ascaris suum

Host species swine

Size 40 um x 70 um

Ova are trichostrongyle type

Nodular worm of swine

Oesophagostomum debtatum

Parasite in which the intermediate host can be the same animal as the definitive host

Significant public health concern

Affects swine

Trichinella spirals

Swine whip worm

Size 50-56 um x 21-25 um

Trichuris suis

Thorny headed worm of swine

Typically found on necropsy

Macracanthorhynchus hirudinaceus

obligate intracellular gram negative bacteria

rickettsial parasites

genus of anaplasma that most commonly causes anaplasmosis in dogs

a. phagocytophilium

anaplasma genus that affects ruminants 

a. marginale 

cells affected by a. phagocytophilium

granulocytes - neutrophils, eosinophils, basophils

vector of a. phagocytophilium

ixodes spp.

vector of a. marginale

multiple tick genus/speciess

ehrilichia genus that usually causes ehrilichiosis in dogs

e. canis

cells affected by e. canis

mononuclear leukocytes - monocytes and lymphocytes

what is the rickettsia genus that causes rocky mountain spotted fever

rickettsia sickettsii

cells affected by rickettsia rickettsii 

endothelial cells lining vessels 

vectors for rickettsia rickettsii

rhipicephalus sanguineus, dermacentor variabilis

protozoal blood parasites 

babesia, cytauxoon felis, plasmodium 

what phylum are the protozoal parasites in

apicomplexa

which protozoan blood parasite affects cats and has a high mortality rate if not treated

cytauzoonfelis

what is the natural host of cytauzoon felis 

the bobcat

vector of cytauxoon felis

amblyomma americanum