Nematodes- Superfamily Trichostrongyloidea

Question 1

Superfamily Trichostrongyloidea

Answer 1

-direct life cycle, L3 infective
-thin bodied
-arrested development
-Eggs: thin shell, oval, avg size (strongylid egg)
-males have bursa
-Dx: differentiating eggs is difficult but combined with CS and seasonality can tell
-age related immunity: cattle>sheep>goats
PPR: sheep, goats, swine (not cattle bc eggs can survive better in cattle poop)
PPP: 3-4 weeks for most

Question 2

Ostertagia ostertagi

Answer 2

Brown stomach worm
Host: #1 parasite in cattle everywhere
Adults and larvae: abomasal mucosal lining
PPP: 3-4 wks
L3 can survive on pasture over winter, but die during spring
Path: caused by L3 emerging from hypobiosis as immature adults in gastric glands–> destroy them, replaced w mucosa that can’t produce needed acids for digestion. this ^ plasma pepsinogen & leads to Moroccan leather appearance of thickened gastric mucosa; raised nodules
CS: d+, bottle jaw
Type I: summer, calves DURING 1st grazing szn, high morbidity, low mortality, eggs and adults are seen, tx w/in 2-3 days, dz occurs mid to late summer. continual buildup of L3 in pasture–> damage outweighs what animal can repair
Type II: winter, calves AFTER 1st grazing szn, L4 arrest @ end of summer. low morbidity, high mortality, few eggs seen. dz occurs during late winter/early spring–>massive synchronized emergence in spring. intermittent d+, more bottle jaw
*exposure needed to acquire immunity
Dx: use CS, grazing history (good for type II), egg counts (type II will be neg), necropsy (moroccan leather)
Tx: anthelmintics effective against arrested L4, larvae, adults, pasture management

Question 3

Teladorsagia circumcincta

Answer 3

Stomach worms
Hosts: sheep and goats
-same as ostertagia but in shoats, CS not as bad
Source of infection: PPR- L3 can’t survive as well in feces
Dx and Tx same as ostertagia except LOTS more resistance

Question 4

Hyostrongylus rubidus

Answer 4

Stomach worm
Host: pigs
Adults: slender, reddish, slightly smaller
Location: stomach
Same as other stomach worms (PPR, PPP, L4 hypobiotic)
Young outdoor pigs mostly affected (A. suum can be both but this is more common outdoors)
Path: hemorrhage–> causes anemia instead of d+
Dx: poor sow syndrome (like Oesoph), eggs in fecal
Tx: anthelmintics effective against hypobiotic larvae…same as ostertagia
“Poor me dropped my hydroflask on my foot now im bleeding”

Question 5

Haemonchus contortus

Answer 5

Barber pole worm
Hosts: #1 parasite for shoats
Adults: 2-3 cm (biggest in abomasum) on abomasal surface, females are candy canes
PPP, PPR, hypobiosis
FAMACHA–> used to ID which shoats are suffering, NOT FOR DX
Path: BIG bloodsuckers–> cause hemorrhagic tracts
Hyperacute haemonchosis: lambs die of hemorrhagic gastritis (massive hemorrhaging)
Acute hemorrhagic anemia: bottle jaw, lathargy
Chronic haemonchosis: wt loss, weakness
Dx: szm- usually mid to late summer when # accumulate on pasture…hx, CS, high FEC, necropsy
MASSIVE resistance

Question 6

Haemonchus placei

Answer 6

Host: cattle

• more present in tropics, less cold resistance
• same as H. contortus
• more acute and chronic cases vs hyperacute
• resistance

Question 7

Zoonotic

Answer 7

A. caninum
A. tubaeforme
A. braziliense
Uncinaria stenocephala

Question 8

Bottle jaw parasites

Answer 8

Bunostonum–> anemia and d+ in YOUNG ruminants
Ostertagia–> just d+ in cattle
Teladorsagia–> just d+ in shoats
Haemonchus spp. –> just anemia