Parastiology MSE life cycles

Leishmania spp.

tsetse fly, Euglenozoa

1. Vector injects infective stage

2. Parasite enters host bloodstream

3. Multiplies asexually

4. Transmissible stage taken up by vector during blood meal

5. Sexual reproduction in vector

6. Infective stages migrate to salivary glands

7. New host infected on next feed

babesia spp.

tick, apicomplexa, sporozoites invade RBCs

1. Vector injects infective stage

2. Parasite enters host bloodstream

3. Multiplies asexually

4. Transmissible stage taken up by vector during blood meal

5. Sexual reproduction in vector

6. Infective stages migrate to salivary glands

7. New host infected on next feed

theileria spp.

tick, apicomplexa, sporozoites invade lymphcytes, merozoites invade RBC

1. Vector injects infective stage

2. Parasite enters host bloodstream

3. Multiplies asexually

4. Transmissible stage taken up by vector during blood meal

5. Sexual reproduction in vector

6. Infective stages migrate to salivary glands

7. New host infected on next feed

plasmodium spp.

mosquito (malaria), apicomplexa

1. Vector injects infective stage

2. Parasite enters host bloodstream

3. Multiplies asexually

4. Transmissible stage taken up by vector during blood meal

5. Sexual reproduction in vector

6. Infective stages migrate to salivary glands

7. New host infected on next feed

giardia intestinalis

apicomplexa

1. Ingestion of infective stage (cyst or oocyte)

2. Excystation

3. Asexual multiplication in intestinal cells

4. Differentiation into sexual forms

5. Gametes fuse

6. Cysts/oocysts shed in faeces

7. Environmental survival until next ingestion

cryptosporidium parvum

apicomplexa

1. Ingestion of infective stage (cyst or oocyte)

2. Excystation

3. Asexual multiplication in intestinal cells

4. Differentiation into sexual forms

5. Gametes fuse

6. Cysts/oocysts shed in faeces

7. Environmental survival until next ingestion

eimeria spp.

apicomplexa

1. Ingestion of infective stage (cyst or oocyte)

2. Excystation

3. Asexual multiplication in intestinal cells

4. Differentiation into sexual forms

5. Gametes fuse

6. Cysts/oocysts shed in faeces

7. Environmental survival until next ingestion

tritrichomonas foetus

Metamonada

1. Direct transmission during copulation (cattle) or faecal oral (cat)

2. Trophozoites colonise in genital tract (cattle) or colon (cat)

3. Reproduce via binary fission

4. No cysts, can’t survive long outside host

toxoplasma gondii

apicomplexa

1. Definitive host sheds unsporulated oocyst

2. Sporulates in environment

3. Intermediate host ingests oocyst

4. Sporozoites invade tissues à form tissue cysts (bradyzoites)

5. Definitive host infected by eating tissue cysts

6. Sexual reproduction in environment

neospora caninum

apicomplexa

1. Definitive host sheds unsporulated oocyst

2. Sporulates in environment

3. Intermediate host ingests oocyst

4. Sporozoites invade tissues à form tissue cysts (bradyzoites)

5. Definitive host infected by eating tissue cysts

6. Sexual reproduction in environment

sarcocystis spp.

apicomplexa

1. Definitive host sheds sporocysts

2. Intermediate host ingests

3. Sporozoites form muscle sarcocysts

4. Definitive host eats infected muscle

5. Sexual reproduction in intestine

6. Sporocysts shed.

fasciola hepatica

Platyhelminth

1. Eggs excreted into water

2. Miracidium hatches and infects snail (IH)

3. Asexual stages in snail à produce cercaria

4. Cercaria encyst on vegetation as metacercaria OR penetrate host

5. Metacercaria excyst in host à migrate to organ

6. Adults produce eggs à excreted

paramphistomes

Platyhelminth

1. Eggs excreted into water

2. Miracidium hatches and infects snail (IH)

3. Asexual stages in snail à produce cercaria

4. Cercaria encyst on vegetation as metacercaria OR penetrate host

5. Metacercaria excyst in host à migrate to organ

6. Adults produce eggs à excreted

schistosoma spp.

Platyhelminth

1. Eggs excreted into water

2. Miracidium hatches and infects snail (IH)

3. Asexual stages in snail à produce cercaria

4. Cercaria encyst on vegetation as metacercaria OR penetrate host

5. Metacercaria excyst in host à migrate to organ

6. Adults produce eggs à excreted

dipylidium caninum

Platyhelminth

1. Eggs/proglottids shed in faeces

2. Arthropod IH ingests eggs à cysticercoid develops

3. DH ingests IH during grooming/feeding

4. Cysticercoid develops into adult tapeworm in intestine

anoplocephala perfoliata

Platyhelminth, orbaditd mite, horse

1. Eggs/proglottids shed in faeces

2. Arthropod IH ingests eggs à cysticercoid develops

3. DH ingests IH during grooming/feeding

4. Cysticercoid develops into adult tapeworm in intestine

moneizia expansia

Platyhelminth, ruminant, orbatid mite

1. Eggs/proglottids shed in faeces

2. Arthropod IH ingests eggs à cysticercoid develops

3. DH ingests IH during grooming/feeding

4. Cysticercoid develops into adult tapeworm in intestine

diphyllobothrium latum

platyhelminth

1. Eggs in water hatch à coracidia

2. 1st IH (copepod) ingests coracidia à procercoid

3. 2nd IH (fish/reptile/amphibian) ingests copepod à plerocercoid in tissue

4. DH ingests 2nd IH (raw/undercooked) à adult in intestine

adenocephalus pacificus

platyhelminth

1. Eggs in water hatch à coracidia

2. 1st IH (copepod) ingests coracidia à procercoid

3. 2nd IH (fish/reptile/amphibian) ingests copepod à plerocercoid in tissue

4. DH ingests 2nd IH (raw/undercooked) à adult in intestine

spirometra erinacei

platyhelminth

1. Eggs in water hatch à coracidia

2. 1st IH (copepod) ingests coracidia à procercoid

3. 2nd IH (fish/reptile/amphibian) ingests copepod à plerocercoid in tissue

4. DH ingests 2nd IH (raw/undercooked) à adult in intestine

strongylus vulgaris

nematoda, intestine —> cranial mesenteric artery

1. Eggs in faeces à develop into infective L3 on pasture

2. L3 ingested

3. Larvae either migrate OR encyst in mucosa

4. Adults develop in gut à eggs pass in faeces

strongylus edentatus

nematoda, liver —> peritoneal cavity

1. Eggs in faeces à develop into infective L3 on pasture

2. L3 ingested

3. Larvae either migrate OR encyst in mucosa

4. Adults develop in gut à eggs pass in faeces

strongylus equinus

nematoda, liver and pancreas

1. Eggs in faeces à develop into infective L3 on pasture

2. L3 ingested

3. Larvae either migrate OR encyst in mucosa

4. Adults develop in gut à eggs pass in faeces

cyathostomins

nematoda, large intestine, possible hypobiosis

1. Eggs in faeces à develop into infective L3 on pasture

2. L3 ingested

3. Larvae either migrate OR encyst in mucosa

4. Adults develop in gut à eggs pass in faeces

haemonchus contortus

nematoda, abomasum

1. Eggs in faeces à develop into infective L3 on pasture

2. L3 ingested

3. Larvae either migrate OR encyst in mucosa

4. Adults develop in gut à eggs pass in faeces

ostertagia ostertagi

nematoda, abomasal gastric glands, possible hypobiosis

1. Eggs in faeces à develop into infective L3 on pasture

2. L3 ingested

3. Larvae either migrate OR encyst in mucosa

4. Adults develop in gut à eggs pass in faeces

trichostrongylus spp.

nematoda, abomasum/SI

1. Eggs in faeces à develop into infective L3 on pasture

2. L3 ingested

3. Larvae either migrate OR encyst in mucosa

4. Adults develop in gut à eggs pass in faeces

ancylostoma caninum

nematoda

1. Eggs shed in faeces (+transplacental/mammary)

2. L3 penetrates skin or is ingested

3. Migrates via bloodstream à lungs à coughed up and swallowed

4. Develop into adults in SI

dirofilaria immitis

nematoda, mosquito, heart worm

1. Mosquito ingests microfilariae from infected dog

2. Develops into L3 in mosquito

3. Injected into next host à migrates to pulmonary arteries à adult

4. Adults produce microfilariae

toxocara canis

nematoda, also transplacental/mammary

1. Eggs with infected larvae ingested

2. Larvae hatch à migrate to liver à lungs

3. Coughed up and swallowed à adult in SI

4. Eggs passed in faeces

pascaris equorum

nematoda, foals

1. Eggs with infected larvae ingested

2. Larvae hatch à migrate to liver à lungs

3. Coughed up and swallowed à adult in SI

4. Eggs passed in faeces

ascaris suum

nematoda, pigs

1. Eggs with infected larvae ingested

2. Larvae hatch à migrate to liver à lungs

3. Coughed up and swallowed à adult in SI

4. Eggs passed in faeces

Filaroides osleri

nematoda, dog trachea

1. L1 passed in sputum/faeces

2. Transmitted via saliva (dam à pup)

3. Larvae migrate to trachea à form nodules à adults lay L1

oxyuris equi

nematoda (pinworm)

1. Female lays egg around anus à quickly infective

2. Horse ingests eggs during grooming/contaminated feed

3. Larvae hatch à develop in large intestine and rectum

4. Adults lay eggs peri-anally

habronema spp.

nematoda, horses, gastric and cutaneous ulcers

1. Eggs or L1 shed in faeces à ingested by fly (IH)

2. L3 develops in fly

3. Horse ingests fly à adult develops in stomach

4. If L3 deposited in wound by flies = cutaneous habronemiasis

trichuris vulpis

nematoda, dogs, whipworm

1. Eggs in faeces à embryonate in environment

2. Ingested by host à larvae attach in SI

3. Move to caecum and mature

tongue worm

arthropoda

1. Eggs shed in nasal secretions or in faeces of DH

2. IH ingests eggs à larvae hatch and migrate à encyst

3. DH infected by eating IH tissues containing larvae

4. Adults develop in nasal passages of DH

haematobia exlgua

arthropod, buffalo fly, manure

1. Adults feed and mate on host

2. Eggs laid on host (fleece, wounds) or in fresh manure

3. Eggs hatch à larvae develop (feed on host tissue/dung)

4. Pupate in environment à adults emerge + find host

bovicola ovis

arthropoda, sheep lice

1. Adults feed and mate on host

2. Eggs laid on host (fleece, wounds) or in fresh manure

3. Eggs hatch à larvae develop (feed on host tissue/dung)

4. Pupate in environment à adults emerge + find host

lucilia cuprina, Chrysomya spp. Sarcophaga spp. Calliphora spp.

arthropoda, blowfly

1. Adults feed and mate on host

2. Eggs laid on host (fleece, wounds) or in fresh manure

3. Eggs hatch à larvae develop (feed on host tissue/dung)

4. Pupate in environment à adults emerge + find host

culicoides spp.

arthropoda, biting midges

1. Adult midges feed on blood

2. Eggs laid in most soil/decaying vegetation

3. Larvae develop into moist substrate à pupate

4. Adults emerge and begin feeding

gasterophilus spp.

arthropoda, bot flies

1. Adult flies lay eggs on horsehair

2. eggs enter during grooming

3. In stomach —> hatch and develop

4. Mature larvae in faeces —> pupate in soil —> adults emerge

ctenocephalides

arthropoda, cat flea

1. Adults feed and mate on host

2. Eggs fall off host into environment

3. Larvae hatch à develop on organic debris

4. Pupate in cocoons à adults emerge + infest host

pulex irritans

arthropoda, human flea

1. Adults feed and mate on host

2. Eggs fall off host into environment

3. Larvae hatch à develop on organic debris

4. Pupate in cocoons à adults emerge + infest host

echidnophaga gallinacea

arthropoda, sticktight flea

1. Adults feed and mate on host

2. Eggs fall off host into environment

3. Larvae hatch à develop on organic debris

4. Pupate in cocoons à adults emerge + infest host

spilopsyllus cuniculi

arthropoda, rabbit flea, repro. triggered by rabbit pregnancy hormones

1. Adults feed and mate on host

2. Eggs fall off host into environment

3. Larvae hatch à develop on organic debris

4. Pupate in cocoons à adults emerge + infest host

rhipicephalus (boopilus) microplus

arthropoda, cattle tick

ONE HOST:

1. Eggs in environment à larvae hatch and attach

2. Nymph and adult stages on same host

3. Engorged female drops off to lay eggs

Ixodes holocyclus, Ixodes cornutus

arthropoda, paralysis tick

THREE HOST:

1. Eggs in environment à larvae hatch à attach à feed à drop

2. Moult to nymph à attach à feed à drop

3. Moult to adults à attach à mate, feed à eggs

rhipicephalus saguineus

arthropoda, brown-dog tick

THREE HOST:

1. Eggs in environment à larvae hatch à attach à feed à drop

2. Moult to nymph à attach à feed à drop

3. Moult to adults à attach à mate, feed à eggs

haemaphysalis longicornis

arthropoda, bush tick

THREE HOST:

1. Eggs in environment à larvae hatch à attach à feed à drop

2. Moult to nymph à attach à feed à drop

3. Moult to adults à attach à mate, feed à eggs

dexmodex spp.

arthropoda, mite - follicles

1. Adults live in/on animal

2. Females lay eggs à hatch à nymphs à adults

3. Spread via direct contact

sarcoptes scabiei

arthropoda, skin burrowing mite

1. Adults live in/on animal

2. Females lay eggs à hatch à nymphs à adults

3. Spread via direct contact

otodectes cynotis

arthropoda, ear mite

1. Adults live in/on animal

2. Females lay eggs à hatch à nymphs à adults

3. Spread via direct contact

pneumonyssoides caninum

arthropoda, nasal mite

1. Adults live in/on animal

2. Females lay eggs à hatch à nymphs à adults

3. Spread via direct contact

ornithonysuss

arthropoda, bird mite

1. Adults live in/on animal

2. Females lay eggs à hatch à nymphs à adults

3. Spread via direct contact

dermanyssus spp.

arthropoda, bird mite

1. Adults hide in environment during day à feed on bird at night

2. Eggs layed off host à hatch à larvae à nymph à adult

Neoparamoeba perurans

protozoa, amoebic gill disease

1. Free living amoeba/trophozoite/ciliate in water

2. Attaches to fish skin or gills

3. Multiplies via binary fission

4. Detaches and survives in environment until attaches to new host

trichodina spp.

protozoa, ciliate ectoparasite

1. Free living amoeba/trophozoite/ciliate in water

2. Attaches to fish skin or gills

3. Multiplies via binary fission

4. Detaches and survives in environment until attaches to new host

ichtyophitius multifillis

protozoa, fresh water white spot

1. Trophonts mature on fish gill/skin

2. Drops off host à form cyst (tomont) in environment

3. Tomon undergoes multiple divisions à theronts (infective)

4. Theronts hatch and actively seek new host

flatworms

helminth

1. Adults on fish lay eggs (host or environment)

2. Eggs hatch à free swimming oncomiracidia

3. Oncomiracidia attach to fish gills or skin

4. Mature into adults and reproduce

dactylogyrus spp.

helminth

1. Adults on fish lay eggs (host or environment)

2. Eggs hatch à free swimming oncomiracidia

3. Oncomiracidia attach to fish gills

4. Mature into adults and reproduce

benedenia spp.

helminth, skin fluke

1. Adults on fish lay eggs (host or environment)

2. Eggs hatch à free swimming oncomiracidia

3. Oncomiracidia attach to fish gills or skin

4. Mature into adults and reproduce

argulids

arthropod, fish lice

1. Adult lice mate on fish

2. Females lay eggs on substrate

3. Eggs hatch à free swimming larvae

4. Larvae attach to fish à develoop into adults