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Flashcards in Nematodes Part 2 Deck (78)
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1

Thelazia californensis
- adult and egg characteristics

Adult
- males and females

Eggs
- embryonated, hatch in uterus of female worm
- larvae L1

2

Thelazia californensis
Lifecycle
Infective stage

1. First stage larvae (L1 in tears) ingested by face fly
2. Molts to L3 in fly
3. L3 larvae are deposited when teh fly feeds around the eye
4. Mature to adults in conjunctiva/lacrymal duct

- L3 larvae are the infective stage

3

Thelazia californensis
What pathology/Clinical signs looks like

Lesions result only from large number of worms
- conjunctivitis, keratitis
- photophobia
- excessive tearing

4

Thelazia californensis
Diagnosis

Observe parasits on eye surface, conjunctival sac

Lachrymal secretions may contain L1 larvae

5

Thelazia califonrnesis treatment

Remove parasites
- manual; brush or irrigation

Ivermectin

Control musca autumnalis (face fly)

6

Diotophyme renale
- common name
- where its found and in what species
- who is the DH
- IH and paratenic hosts if any

- giant kidney worm
- found in the kidney of dogs, wolves, mink, foxes, rarely found in cats, humans, pigs, cattle
- the DH = minkes
- IH = annelid, they live on the surface of crayfish
- paratenic hosts = fish, frogs

7

Dioctophyme renale
- adult and egg characteristics

Adults
- large

Eggs
- barrel shaped, bipolar plugs, rough shell
- nonembryonated
- found in urine

8

Dioctophyme renale
Lifecycle
Infective stage

1. Eggs leave DH via urine - viable up to 5 years in environment
2. Ingested by annelid=IH and develop to an L3
3. Paratenic host may ingest annelid/crayfish where the L3s encyst
4. DH ingests the annelid/crayfish or paratenic host
5. L3 excysts and leaves the intestine, migrates to the kidney and matures

Infective stage = L3

9

Dioctophyme renale
- clinical signs and pathogencitiy

Clinical signs
- typically no clinical signs
- though adults can block the ureter, cause peritonitis and renal failure

Pathology: usually the right kidney only

10

Dioctophyme renale
Diagnosis and treatment

Diagnosis
- urine sedimentation - they sink
- adults (laparotomy, hysterectomy)

Treatment
- none
- remove adults or kidney?

11

Pearsonema plica and pearsonema feliscati
- common name
- where its found and in what species
- IH and paratenic hosts if any

- urinary bladder worm
- found in the urinary bladder and pelvis of kidney. P. Feliscati is found in cats, and p. Plica is found in dogs, wolves and foxes
- paratenic host = earthworm

12

Pearsonema spp.
Adult and egg characteristics

Adults are slender and filamentous
Eggs have bipolar ends

13

Pearsonema spp.
Lifecycle and infective stage

1. Eggs leave DH via urine - larvate to L1
2. Eggs with L1 ingested by earthworm - L1 in tissues of earthworm. So its a partentic host bc it does not develop within the earthworm
3. DH ingests earthworm - larvae released in intestine
4. L1 excysts - penetrates intestine, matures in mucosa of urinary bladder.

14

Pearsonema sp. clinical signs

- mostly asymptomatic
- irritation of bladder mucosa, cystitis

15

Pearsonema spp.
Diagnosis and treatment

Diagnosed in urine

Treatment: non approved
Febendazole, ivermectin, may need to repeat

16

Eucoleus aerophilus and eucoleus boehmi
- common name
- which worm is found where and in which species
- IH?

- lungworm
- E. Aerophilus found in respiratory tract of dogs, cats, foxes
- E. Boehmi found in the nasal cavity, paranasal sinuses of dogs and foxes
- direct lifecycle = no IH

17

Eucoleus spp.
- adult and egg characteristics

Adults: male and female

Eggs: main difference is aerophilus looks netted while boehmi shell looks pitted, there are little dots everywhere

18

Eucoleus spp.
Lifecycle and infective stage

1. Adults in lungs, eggs leave DH via feces
2. Eggs larvate to L2 once in environment
3. DH ingests egg with L2 larvae released into intestine and penetrat mucosa of either a fox or a dog.
4. Larvae migrate to lungs, mature in bronchioles, bronchi and trachea

19

Eucoleus spp.
Clinical signs and pathogenicity

- usually asymptomatic
- severe infections: coughing, nasal discharge, bronchitis, pneumonia, anorexia, dyspnea. Secondary infections possible
- mucosa edema, inflammation, hemorrhage

20

Eucoleus spp.
Diagnosis and treatment

Diagnosis
- fecal exam bc they are coughed up then swallowed
- differentiate from similar eggs

Treatment
- fenbendazole treat very well
- ivermectin

21

Identifying trichuris v. Pearsonema/eucoleus

Trichuris
- Much larger
- smooth shell
- very symmetrical plugs
- at 40x mag you will find rings on trichuris plugs and pearsonemas wont have that.

Pearsonema
- smaller
- slightly off-centered plugs

22

Filaroides hirthi and filaroides osleri
- common name
- which worm is found where and in which species
- IH?
- geographic distribution

- lungworm
- F. Hirthi found in lung parenchyma of dogs and coyotes
- F. Osleri is found in nodules at the bifurcation of the trachea also in dogs and coyotes
- direct lifecycle = no IH
- F. Osleri found in western, midwestern US and Canada

23

FIlaroides hirthi and filaroides osleri
Characteristics of adult and larva

Adults - filamentous
Larva - "kinky" tail, lacks dorsal spine

24

Filaroides spp. Lifecycle

1. L1 larvae leave DH - feces, saliva, respiratory secretions
2. new DH ingests L1
3. Migrate to lungs via lymphatics or venous system

25

Filaroides spp.
Diagnosis

Can find in fecal floatation and fecal sedimentation
Can also do baermann on saliva material

-rads
- endoscope
- often misdiagnosed as kennel cough

26

Filaroides spp.
Treatment

- fenbendazole
- ivermectin
- inj. Doramectin
- remove nodules

27

Aelurostrongylus abstrusus
- common name
- where its found and in what species
- IH and paratentic hosts?

- feline lungworm
- found in the lung parenchyma of cats
- IH: land snails and slugs
- paratenic hosts: rodents, birds, amphibians, reptiles

28

Aelurostrongylus abstrusus
Adult and egg characteristics

Adults
- filamentous

Eggs
- ellipsoid in lungs, larvated
- "hatch" in lungs with a kindy tail and have a dorsal spine at the end of the tail

29

Aelurostrongylus
Lifecycle
Infective stage

1. Eggs in nests in lung nodules - L1 hatch and leave DH via feces (coughed up and swallowed)
2. L1 is ingested by land snail - IH develop to L3
3. Paratenic host may ingst snail or slug and have the L3s encyst.
4. DH ingests snail or slug or paratenic host. Usually its a paratenic host (roden or reptile) since cats dont eat snails often
5. L3 excysts - leaves intestine, migrates to lungs, matures

30

Aelurostrongylus spp.
Clinical signs and pathogenicity

Clinical signs
- light infections: asymptomatic
- mod. Infections: coughing, anorexia
- heavy infections: chronic cough, dysnpea, diarrhea, wasting

Nodules on lung surface - milk fluid, eggs, larvae