STRONGYLIDS LECTURE 4 & 5 Flashcards
Name the 4 major super families of the strongylids
1) Trichostrongyloideas
2) Strongyloidea
3) Ancylostomatoidea
4) Metastrongyloidea
What’s the most important superfamily for ruminants?
Trichostrongyloidea
What kind of mouths do Trichostrongyloidea have?
simple mouths – no teeth since they do only feed on liquids
How do Trichostrongyloidea feed?
Feed on liquid and mucus. Minority are blood suckers
Trichostrongyloidea always have an __ infective stage
L3
Trichostrongyloidea have a ___ life cycle
direct
Trichostrongyloidea PPP is how many weeks?
2-4 (from infection to the complete end of lifecycle)
Where do Trichostrongyloidea reside in the ruminant?
Stomach or small intestine
Do Trichostrongyloidea generally migrate?
no, not generally
The Trichostrongyloidea burrow into the ____ as ___ and emerge as ____ or immature adults
in the mucosa as L3 and emerge as L4
3 parasites of the abomasum of ruminants; what are they?
1) Haemonchus
2) Teladorsagia (sheep) /Ostertagia (cattle)
3) Trichostrongylus
Where does Ostertagia ostertagi reside?
abomasum of cattle ** VERY COMMON & IMPORTANT NEMATODE
Ostertagia ostertagi are considered what kind of feeders?
they have simple mouths and are mucus browsers
Where do Ostertagia ostertagi reside in abomasum?
Tucked away in the mucus layer in the lining of the stomach
Where do Teladorsagia circumcincta reside?
abomasum of sheep and goats
Life cycle of the Ostertagia / Teladorsagia:
(L3) ingested → exsheath in rumen → move to abomasum → penetrate in mucosal glands → moult to L4 → moult to adult → emerge from gland and lie in mucus layer on the surface
Ostertagia / Teladorsagia PPP?
~18 days
Whats the inhibition of development of Ostertagia / Teladorsagia?
1) incoming L3 pushing into tissue and glands
2) developing L3
3) developing L4
4) can be inhibited as L4 (early L4) so they can stop and sit there waiting for a later time so it can be longer than 18 day PPP
5) can continue again as developing L4
6) become an adult
Why does Ostertagia / Teladorsagia inhibit their development?
L3 sense the season is changing and knows the eggs wont have a chance because it’s too cold out so enters a period of inhibition
How does Haemonchus feed?
blood sucking
What does their feeding habits lead to?
Severe anemia
True or False: Haemonchus is highly pathogenic
TRUE
What kind of climate does Haemonchus like?
warmer climates
True or false: Haemonchus is very prolific?
True lays around ~10,000 eggs per day