Lecture Quiz 2 - Exam 1 - Nematodes - Strongyloidea

Front 1

Describe Chabertia ovina.

Back 1

1. Strongyloidea
2. Non-equine strongyle - ruminant (sheep/goats)
3. Large mouthed bowel worm
4. Prepatent period ~ 6 weeks
5. 13-20 mm long
6. Characteristic large buccal capsule: plug-feeder

Front 2

What are some clinical signs of Chabertia ovina?

Back 2

1. Usually subclinical
2. Large numbers of plug-feeding adults can cause mucosal ulcerations: local hemorrhage, protein loss into the gut, diarrhea with blood and mucus, weight loss, possible anemia, and decreased wool quality.

Front 3

What is the diagnosis for C. ovina?

Back 3

1. Detection of typical strongyle-type egg
2. Coproculture and ID of L3 needed for definitive diagnosis.

Front 4

What is the treatment and control for C. ovina?

Back 4

Same as other related parasites.

Front 5

What is Oesophagostomum spp?

Back 5

1."Nodular worm" - reflects lesions produced in large intestinal wall
2. Adults only 3/4 inch long
3. Eggs = strongyle type

Front 6

What is the life cycle of Oesophagostomum?

Back 6

Adults in large intestine are surface feeders; Eggs in feces ( L1 --> L3 in environment)

L3 is ingested --> mucosal encystment --> migrate to colon in submucosa --> emerge to become adults

Prepatent period is 6-7 weeks

Front 7

What is the pathology - primary infection of Oesophagostomum?

Back 7

Relatively harmless

Enteritis if large number larvae emerge from mucosal cysts = diarrhea

Adult feeding activities: inflammation +/- thickening of mucosa

Front 8

What is the pathology - re-infections of Oesophagostomum?

Back 8

Produce lesions, possible clinical signs

Localized immune-mediated reaction around larvae in mucosa: formation of nodules or "mini-abscesses"

Front 9

What are the lesions or nodules of Oesophagostomum?

Back 9

Larvae persist in nodule for < 3 months

Nodule contents eventually caseate and calcify: larvae either leave or become trapped and die

Front 10

What are the clinical signs of Oesophagostomum?

Back 10

Nodules interfere with function of large intestine

Most common signs are anorexia, weight loss, diarrhea, poor wool quality, etc...Rarely do nodules rupture

Front 11

What is the diagnosis of Oesophagostomum?

Back 11

Detect typical strongylid eggs on fecal exam

No eggs during pre-patent period when larval emergence can cause diarrhea etc...

Necropsy: detection of nodules

Front 12

What is Stephanurus dentatus?

Back 12

Swine kidney worm

Adults: stout, 1-1.5 inches long, cream colored; males have poorly developed bursa and thick-walled "squarish" buccal capsule

Eggs = typical strongyle type and will be in urine sediment

Front 13

What is the life cycle of Stephanurus dentatus? (Prepatent period = 9-16 months)

Back 13

Direct cycle: earthworms can serve as paratenic hosts

Infection acquired by: ingestion of L3; skin penetration by L3; ingestion of L3 in earthworms that can serve as paratenic hosts

L3 migrate from gut to liver (2-9 months) and can cause extensive liver damage --> exit liver capsule --> retro-peritoneally to kidney wall, ureters (mature to adults in cysts); Cysts communicate with ureter --> eggs passed in urine

Front 14

What kind of lesions occur from Stephanurus dentatus and what are the signs?

Back 14

Skin lesions
Liver fibrosis, cirrhosis, abscesses, adhesion

Vague signs: unthriftiness, emaciation, death

Adults in renal tissues = nonpathogenic

Front 15

How do you diagnosis Stephanurus dentatus?

Back 15

Clinical signs develop in hogs in endemic area (mainly SE US)

Detects eggs in URINE sediment (pigs be 2 years old)
Detect worms at necropsy

Front 16

What is Syngamus trachea?

Back 16

1. "Gapeworm" or "Y-worm"
2. Adults in tracheal lumen
3. Fairly common in game birds
4. Bright red = suck blood
5. Males are small (2-6 mm); females are larger ( <20 mm)
6. Male and female in permanent copulation = Y form

Front 17

Explain the structure of Syngamus trachea eggs.

Back 17

1. Atypical strongylid eggs
2. Bipolar opercula
3. Shaped like a hybrid of Nematodirus and trichuris eggs

Front 18

What is the life cycle of Syngamus trachea?

Back 18

1. Adults in trachea produce eggs: eggs coughed up and swallowed; passed in feces in non-embryonated stage

2. Infective L3 develops within egg in 1-2 weeks

3. Infection acquired by ingestion of L3: liver-lung-tracheal migration --> gut mucosa --> hepatic portal vein --> liver --> vena cava --> heart --> lungs --> trachea

Mature and copulate in trachea: attach to tracheal mucosa and suck blood (prepatent period ~ 17-20 days)

Front 19

What are the signs and lesions of Syngamus trachea?

Back 19

Larval migration: hemorrhage, edema, possible pneumonia in heavy infections

Adults in trachea: obstructive tracheitis - males deeply embedded in mucosa cause nodules; catarrhal tracheitis with excess mucus; spasmodic dyspnea: head shaking, neck extension, gaping, open-mouth breathing

Front 20

How can you diagnosis Syngamus trachea?

Back 20

Definitive diagnosis based on: detect eggs in feces (differentiate from smaller, brownish Capillaria eggs also with polar plugs) and detect adults attached to lower trachea surrounded by blood streaked mucus

Front 21

How can you control the spread of Syngamus trachea?

Back 21

1. Avoid keeping birds on same ground for long periods of time

2. Keep pens dry: L3 and paratenic hosts survive in moist areas

3. Minimize cross-transmission among birds

Front 22

What are clinical signs of Cyathostoma variegatum?

Back 22

Severe respiratory distress: dyspnea, head shaking

Front 23

What is this?

Back 23

Syngamus trachea egg