2. Digeneans

Large flukes mostly in the bile ducts of ungulates

Large flukes mostly in the bile ducts of ungulates

Family Fasciolidae

Usually in digestive tract of fishes, amphibians, reptiles, birds and mammals

Superfamily Paramphistomoidea

common sp. under the family Fasciolidae

Fasciola hepatica, F. gigantica, Fascioloides magna

Common liver fluke

Fasciola hepatica

seen in the bile ducts of large and small ruminants, pigs, hare, rabbits, beavers, coypus, elephants, horses, dogs, kangaroos, cat, and man

Fasciola hepatica

what diseases do F. hepatica cause?

liver rot or liver fluke disease

Snail IH in Europe, Asia, Africa and North America

Lymnea truncatula

Snail IH in the USA

Stagnicola (Lymnaea) bulimoides and L. columella

Snail IH in Australia and New Zealand

Lymnaea tomentosa and columella

Snail IH in South America

Lymnaea viator and cubensis

How long do Miracidium hatch? at what temp?

10-12 days at 26C

1 egg = ? metacercariae

approx. 600 metacercariae because of paedogenesis or polyembryony

Pathogenesis of flukes

"a. mechanical destruction

b. toxic excretory and secretory (ES) products

c. loss of blood"

Consequence of pipestem fibrosis

atrophy of the liver due to back pressure, cirrhosis and possibly jaundice

Anemia is caused by ______. This induces bile duct collagen deposition.

parasite proline

occurs after sudden massive ingestion of metacercariae

Acute fasciolosis

occurs after longer massive ingestion of metacercariae. Course of 4-8 weeks.

Subacute fasciolosis

following prolonged moderate intake of metacercariae

Chronic fasciolosis

most common form of fasciolosis. Causes moderate cholangitis

Subclinical fasciolosis

Drug of choice for flukes

triclabendazole

Drug for 1 day to 6 weeks old flukes

Diamphenetide

Drug for 6 weeks and older flukes

Rafoxanide, closantel, nitroxynil

Drug for adult flukes

Niclofolan, Albendazole, Oxyclozanide, Brotianide, Clorsulon, Netobimin

Large liver fluke

F. gigantica

"more common in Africa, Asia (including the Phils.),

Hawaii and tropical and subtropical regions"

F. gigantica

most important helminth of livestock

F. gigantica

IH of F. gigantica

"Lymnaea auricularia

rubiginosa (Southeast Asia,

Philippines), L. natalensis

(Africa), L. viridis (China,

Hawaii, Japan), L. rufescens

(Indian subcontinent), L. acuminata (Malaysia)"

"causes anemia, loss of weight,

hypoproteinemia, submandibular edema and

sometimes death in Asian elephants"

F. jacksoni

"Large

American liver fluke, giant deer

fluke

in bile ducts and or liver tissue

of white-tailed deer, other

Cervidae (roe deer, moose,

elk, fallow deer) wapiti, cattle,

bison, sheep, goat, pig, horse,

etc. of North America, central

Europe, Mexico and South

America"

F. magna

"excretory system produces large amount of this pigment (black iron porphyrin pigment); the pigment accumulates in

liver, omentum, kidneys and other internal organs of hosts"

Melanin

"in small intestine, rarely

the stomach and colon,

of humans, pigs and

dogs in the Orient

(South and East Asia

such as China,

Indonesia, Vietnam,

India and Thailand)

ceca not branched"

Fasciolopsis buski

IH of F. buski

"flat, spiralled freshwater snails (Planorbis,

Hippeutis and Segmentina)"

F. buski metacercaria are formed in what vegetation

water chestnut Eliocharis tuberosa), water calthrop (Trapa natans, T. bicornis), lotus and bamboo

Pathogenesis of F. buski

"heavy infection – diarrhea, ulceration and abscessation

of intestinal mucosa, anemia, and hypersensitization in

humans"

Treatmend for F. buski

Albendazole and Praziquantel

parasite in gall bladder and digestive tract of elks and wild goats in the former USSR and Poland

Parasfciolopsis fasciolaemorpha

IH of P. fasciolaemorpha

Planorbis corneus

Superfamily Paramphistomoidea commonly known as

Amphistomes

"in rumen of domestic

animals throughout the

world, conical and pink

when fresh"

Paramphistomum cervi

Paramphistomids in European cattle

P. daubneyi

Paramphistomids in Australia

P. ichikawai

Paramphiostomids in rumen and reticulum of ruminants

Calicophoron, C. calicophorum, C. crassum

Paramphistomids in rumen and abomasum

Gigantocotyle formosanum

Paramphistomids in bile ducts and liver

Explanatum: E. explanatum, E. bathycotye, E. anisocotylea

in rumen and reticulum, testes – horizontal

Gastrothylax

"ventral pouch – very large, extending over

the whole ventral surface to posterior sucker"

G. crumenifer

"in rumen of bovids, testes – tandem

· uterus – runs forward in midline"

Fischoederius

"most common amphistome in cattle and

water buffaloes in the Philippines"

F. elongatus

IH of F. elongatus

Gyraulus convexiusculus, Lymnaea philippinensis

Carmyerius sp.

C. synethes, C. spatiosus, C. gregarius

"in rumen of water buffaloes

in the Philippines"

Velasquezotrema brevisaccus

Gastrodiscid flukes

"Gastrodiscus aegypticus

Homologaster paloniae

Gastrodiscoides hominis "

Life cycle of amphistomes

similar to F. hepatica

IH of amphistomes

freshwater or amphibious snails

Pathogenesis of amphistomes

"acute or intestinal amphistomosis

chronic amphistomosis

hepatic amphistomosis"