Canine/Feline Cestodes Flashcards Preview

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Flashcards in Canine/Feline Cestodes Deck (59):
1

Dipylidium caninum-Common Name

Common tapeworm, cucumber tapeworm, double pored dog tapeworm, "creeping seeds", flea tapeworm

2

Dipylidium caninum-Hosts

DH: dogs, cats
IH: Fleas (Ctenocephalides spp.) and louse (Trichodectes canis)
*Zoonosis

3

Dipylidium caninum-Identification

Adults: max length 50cm
Proglottid is elongate, has 2 sets of repro. organs with bilateral genital pores. Single segments passed
Eggs: packets 230 x 170 um containing 10-20 eggs 35-40 um

4

Dipylidium caninum-Life Cycle

Indirect. PPP = 21 days
Passed segments are active→egg packets expelled by active segment→IH ingests egg (oncosphere L1) (flea must be larval stage to ingest, louse in any life stage can ingest)→ oncospheres develop into cysticercoids in the abdominal cavity of IH→DH eats the IH

5

Dipylidium caninum-Site of Infection

Adults: in small intestine
Larval stage (cysticercoid) in flea/louse

6

Dipylidium caninum-Pathogenesis and Lesions

Adults are largely non-pathogenic
Crawling segments may be uncomfortable

7

Dipylidium caninum-Clinical Signs

Excessive grooming of perineum, scooting anus on floor

8

Dipylidium caninum-Diagnosis

Presence of segments around perineum,
Adhesive tape or Scotch tape method: stick tape to perianal area, stick tape to slide and examine for eggs

9

Dipylidium caninum-Treatment and Prevention

Cestocide, flea control important.
Treatment of environment with insecticides to eliminate fleas/lice

10

Echinococcus granulosus-Common Name

Hydatid tapeworm

11

Echinococcus granulosus-Hosts

DH: Dogs
IH: herbivores and humans
*Zoonosis

12

Echinococcus granulosus-Identification

Adult: 6mm long with 3-4 segments, scolex with 4 suckers and 2 rows of hooks
Hydatid cyst (w/in IH): brood capsules and scolices, fluid filled, 5-10cm but up to 50cm in diameter
Eggs: 25-40 um in diameter, brown color, radial striations on shell, presence of 6 embryonic hooks

13

Echinococcus granulosus-Life Cycle

Indirect. PPP = 45-60 days
Adult sheds 1 gravid segment with eggs into feces→ develop into oncospheres that are viable in ground for up to 2 yrs.→IH ingests egg→ egg hatches→ hexacanth larva penetrates the intestine, migrates to liver and lungs of IH→ forms hydatid cyst→ grows and matures in 6-12 mths→ DH ingests infected IH→scolices evaginate and attach to the mucosa of the small intestine and mature in DH

14

Echinococcus granulosus-Site of Infection

Small intestine in DH.
Unilocular hydatid cysts in liver, lungs and other organs in IH and humans

15

Echinococcus granulosus-Pathagenesis and Lesions

Nonpathogenic within DH.
Within human IH, hydatid develops in pulmonary or hepatic site causing pathogenesis

16

Echinococcus granulosus-Clinical Signs

No clinical signs in DH.
In humans, respiratory symptoms and with many hydatids in the liver may cause gross abdominal distension

17

Echinococcus granulosus-Diagnosis

Eggs in fecal flotation or with Adhesive/Scotch tape method

18

Echinococcus granulosus-Treatment and Prevention

Anthelmintic treatment, removal of stray dogs, prohibition against feeding uncooked offal

19

Echinococcus multilocularis-Common Name

Alveolar hydatid tapeworm

20

Echinococcus multilocularis-Hosts

DH: Dogs and Cats
IH: Cows, equines, swine and rodents
*Zoonosis

21

Echinococcus multilocularis-Identification

Adult: 6mm long with 4-5 segments, scolex with 4 suckers and 2 rows of hooks
Hydatid cysts (w/in IH): Alveolar hydatid cyst, not confined by a capsule, exogenous budding
Eggs: taeniid type, brown, 25-40 um, radial striations in shell, 6 embryonic hooks

22

Echinococcus multilocularis-Life Cycle

Indirect. PPP = 28 days
Adult sheds 1 gravid segment with eggs into feces→ develop into oncospheres that are viable in ground for up to 2 yrs.→IH ingests egg→ egg hatches→ hexacanth larva penetrates the intestine, migrates to liver and lungs of IH→ forms hydatid cyst→ grows and matures in 6-12 mths→ DH ingests infected IH→scolices evaginate and attach to the mucosa of the small intestine and mature in DH

23

Echinococcus multilocularis-Site of Infection

Adults: Small intestine
Hydatid cysts: Liver

24

Echinococcus multilocularis-Pathogenesis and Lesions

Usually non-pathogenic.
In IH, alveolar or multilocular cyst grows large and can cause pressure necrosis of the liver and surrounding tissues. Alverolar hydatid is slow growing and eventually fatal

25

Echinococcus multilocularis-Clinical Signs

None in DH.
Invasive growth in humans/IH can be fatal

26

Echinococcus multilocularis-Diagnosis

Eggs in fecal flotation.
Eggs from Adhesive/Scotch tape method
Morphologically indistinguishable from Taenia eggs

27

Echinococcus multilocularis-Treatment and Prevention

Anthelmintic treatment, removal of stray dogs, prohibition against feeding uncooked offal

28

Taenia crassiceps-Hosts

DH: Foxes, dogs
IH: Small rodents
*Zoonosis-Abdominal cavity and the eye

29

Taenia crassiceps-Identification

Adult: scolex with 4 suckers up to 2 m long, rectangular segments with unilateral genital pores
Cysticerci: in abdominal cavity of IH, asexual budding
Eggs: brown color, radial striations in the shell, 6 embryonic hooks, indistinguishable from Echinococcus spp.

30

Taenia crassiceps-Life Cycle

Indirect. PPP 6-9 wks.
Taeniid segments shed from DH in feces→segments release eggs in environ.→eggs develop to oncospheres→oncosphere ingested by IH→enter to small intestine and go to abdominal cavity w/in IH→develops to second-stage larva (cysticercus)→buds into multiple cysticerci→DH ingests IH→develop into adult in small intestine

31

Taenia crassiceps-Site of Infection

Small intestine

32

Taenia crassiceps-Pathogenesis and Lesions

Zoonosis→in humans it can infect the eye and cause blindness

33

Taenia crassiceps-Clinical Signs

Usually asymptomatic

34

Taenia crassiceps-Diagnosis

Eggs in fecal flotation
Echinococcus and Taenia eggs are indistinguishable

35

Taenia crassiceps-Treatment and Prevention

Cestocidal drugs
Prevent eating offal

36

Taenia pisiformis-Hosts

DH: Dogs
IH: Rabbits

37

Taenia pisiformis-Identification

Adults are several meters

38

Taenia pisiformis-Life Cycle

Indirect. PPP = 56 days
Taeniid segments shed from DH→segments release eggs into environ.→develop into oncospheres→oncosphere ingested by IH→enters small intestine and migrates to liver and peritoneum in IH→develops into second-stage larva (cysticerus)→DH ingests cysticercus→develops into adult in small intestine of DH

39

Taenia pisiformis-Site of Infection

Adults: Small intestine of DH
Cysticerci: Liver and peritoneum of IH

40

Taenia pisiformis-Pathogenesis and Lesions

Non-pathogenic

41

Taenia pisiformis-Clinical Signs

Asymptomatic

42

Taenia pisiformis-Diagnosis

Eggs on fecal flotation

43

Taenia pisiformis-Treatment and Prevention

Cestocidal drugs
Prevent eating offal

44

Taenia taeniaeformis-Hosts

DH: Cats
IH: Rodents, humans
*Zoonosis

45

Taenia taeniaeformis-Identification

Adults: 60cm
Eggs: 25-40 um

46

Taenia taeniaeformis-Life Cycle

Indirect. PPP = 6 wk.
Taeniid segments shed from DH→segments release eggs into environ.→develop into oncospheres→oncosphere ingested by IH→enters small intestine and migrates to liver→develop into second-stage larva (strobilocercus)→DH ingests strobilocercus→develop into adult in small intestine of DH

47

Taenia taeniaeformis-Site of Infection

Adults: Small intestine in DH
Strobilocercus: Liver of IH

48

Taenia taeniaeformis-Pathogenesis and Lesion

Non-pathogenic

49

Taenia taeniaeformis-Clinical Signs

Asymptomatic

50

Taenia taeniaeformis-Diagnosis

Eggs on fecal flotation

51

Taenia taeniaeformis-Treatment and Prevention

Cestocidal drugs
Prevent eating offal

52

Diphyllobothrium latum-Common Name

Broad Fish Tapeworm

53

Diphyllobothrium latum-Hosts

DH: Dogs, cats, pigs, humans
IH: Copepod crustacean, Freshwater fish
*Zoonosis

54

Diphyllobothrium latum-Identification

Adults: 12m long, scolex without suckers, 2 slot-like grooves called bothria for attachment, square segments shed in groups
Eggs: Operculate, light brown, 60 um

55

Diphyllobothrium latum-Diagnosis

Fecal sedimentation
Egg can be confused with Fasciola hepatica (130 um) but are half the size

56

Spirometra spp.-Common Name

Zipperworm
Causes Sparganosis in humans

57

Spirometra spp.-Hosts

DH: Dogs, cats
IH: Crustaceans (host procercoid), Water snakes, frogs, rodents, birds (host plerocercoids)
*Zoonosis

58

Spirometra spp.-Identification

Adults: 2 m in length, scolex without suckers, but with 2 bothria, segments shed in groups
Plerocercoids: 4-10 cm in length
Eggs: Operculate, light brown, 60 um

59

Spirometra spp.-Diagnosis

Fecal sedimentation
Egg can be confused with Fasciola hepatica (130 um) but are half the size