Lecture 18 strongyles of ruminants

Question 1

what is the family and 2 genera of the strongyles of ruminants

Answer 1

family: chabertiidae
genera: chabertia and oesophagostomum

Question 2

what are two features of chabertia and what are the hosts

Answer 2

bell shaped buccal capsule with NO teeth
1.5-2 cm 
tiny leaf crown
holds onto chunks of mucosa- tissue feeder
sheep, goats, cattle

Question 3

where are chabertia located in the host

Answer 3

colon (LI)

Question 4

what is the life cycle of chabertia

Answer 4

• L3 exsheaths in small intestine
• enters mucosal glands
• moults to L4
• L4 returns to lumen
• migrates to large intestine
• final moult in large intestine
- NO EXTRA INTESTINAL MIGRATION

Question 5

what is the PPP of chabertia

Answer 5

8 weeks

Question 6

what is the species of chabertia and what effects does it have on the host

Answer 6

ovina

• feed on mucosa
• cause hemorrhage
• excess mucus production
• diarrhea

Question 7

what climate will chabertia occur in

Answer 7

chabertia ovina will be in temperate areas

Question 8

how many worms of chabertia ovina are pathogenic and what is the fecundity of female worms

Answer 8

200 are pathogenic and females lay 3000 eggs a day (high fecundity)

Question 9

what is the common name for oesophagostomum

Answer 9

nodule worms- large nodules in the small intestine

Question 10

what are the 4 species of oesophagostomum, what host do they occur in and where in the host

Answer 10

Oe. radiatum, cattle, cecum
Oe. columbianum, sheep, colon
Oe. venulosum, sheep, cecum
Oe. dentatum, pig, colon

Question 11

what is the lifecycle of oesophagostomum

and what is the PPP

Answer 11

L3 migrates into glands in small &/or large intestine L4 emerges and migrates to large intestine
- PPP is 5-6 weeks

Question 12

what are the features of Oe. radiatum and what is its common name

Answer 12

cylindrical buccal capsule
small leaf crown (basically none)
no external leaf crown
cervical collar in 2 parts
- common name- the nodule worm of cattle

Question 13

what are 3 effects on the host of Oe. radiatum and what is the host

Answer 13

• susceptible (young) host, no reaction
• resistant animals, intense reaction
• nodule filled with eosinophils, larva killed, caseous lesion calcifies
“pimply gut”
• nodules cause Hb & plasma proteins to leak into gut
• interfere with gut motility
• anorexia, reduced weight gains
• adults cause diarrhoea
• strong immunity by 12 months of age- no reaction after this therefore low pathogenicity
- host is cattle

Question 14

what is the effect on the host of Oe. dentatum and what is the host

Answer 14

• common parasite of pigs; more prevalent in northern states
• life cycle as for Oe. radiatum; nodules much smaller
• less pathogenic than Oe. radiatum
• can cause unthriftiness in pigs

Question 15

what are the two oesophagostomum of sheep and which one is more pathogenic, where are they found geographically

Answer 15

Oe. columbianum (more pathogenic)- northern NSW and Queensland
Oe. venulosum- VIC

Question 16

what is a strongyle of the pig that has the eggs passed in the urine

Answer 16

stephanurus dentatus- kidney worm of the pig

Question 17

where are stephanurus dentatus worms found in the body of the host and what is the host

Answer 17

attached to the ureter or in the perirenal fat

pig

Question 18

what is the distribution of the stephanurus dentatus

Answer 18

limited to warm, moist areas in Australia

tropical and subtropical areas worldwide

Question 19

what is the lifecycle of stephanurus dentatus

Answer 19

• egg passed in urine****->L3 in 3-5 days
• L3 ingested or can penetrate skin
• migrate to liver via portal system (3
days) or aorta (8-40 days)
• migrate in liver for 2-3 months
• migrate to perirenal area
• may migrate anywhere in body

Question 20

what is the PPP of stephanurus dentatus

Answer 20

9 months

Question 21

what is the pathogenesis of stephanurus dentatus

Answer 21

• migrating larvae can produce lesions, or abscesses anywhere in carcass
• liver migration causes elevation in liver enzyme concentrations (AST)- diagnostic
• affected pigs lose weight
• organs condemned at slaughter

Question 22

what is the one important strongyle of birds

Answer 22

sygamus trachea- the gape worm

Question 23

where is syngamus trachea located in the host and what is the host

Answer 23

located in the trachea in birds (poultry)

Question 24

what are the features of syngamus trachea

Answer 24

cup shaped buccal capsule
up to 10 teeth
L1-L3 OCCUR IN THE EGG
and oh yeah…THE MALE AND FEMALE ARE ATTACHED- y-shaped, male is tiny

Question 25

what is the lifecycle of syngamus trachea

Answer 25

• eggs coughed up and swallowed, passed in faeces
• 2 moults occur within egg (L1-L3 within the egg)
• egg or infective larvae (L3) may be ingested by birds, or slugs, snails and earthworms may act as
  paratenic (no development) hosts
• larvae penetrate intestinal wall and are carried in the blood via the liver to the lungs, then
  break out into alveoli and migrate to trachea
• prepatent period 2 weeks

Question 26

what is the pathogenesis of syngamus trachea

Answer 26

• cause excess mucus production
• block airways
• respiratory distress - birds stand “gaping”
• blood feeders

Question 27

how do you diagnose syngamus trachea

Answer 27

eggs (L1-L3) in feces

eggs are ellipsoidal and thin shelled with a thick operculum on both sides