Lecture 35 - Strongyles Flashcards
describe small strongyles
- most common and important parasites of horses
- small, red worms
T/F: cyanthostominosis affects horses of any age
TRUE
describe the life cycle of small strongyles
- L3s migrate to mucosa and either arrest or directly develop
- encysted L4s are triggered for various reason
- adult worms in lumen of cecum/large intestine
what is the cause of pathology in small strongyle infections
L4s
why may strongyle count be low on a FEC during pathology
due to arrested L4s in mucosa not passing in feces
what are the forms of pathology for small strongyles
- granulomatous colitis
- larval cyanthostominosis (sudden eruption of large numbers of arrested larvae)
what is a serious concern when treating small strongyles
loss of premunition as eruption can occur post deworming
how is larval cyanthostominosis addressed in treatment
include anti-inflammatories while deworming
what are the clinical signs of small strongyles infections
- persistent D+
- ventral edema
- hypoproteinemia
- weight loss, poor BCS
what diagnostic test should be used when small strongyles is a differential
McMasters
what is the control program for small strongyles
- target arrested L4s in treatment
- focus treatments during seasons of peak transmission
- utilize FECRT
what are the 3 species of large strongyles
- S. vulgaris
- S. equinus
- S. edentatus
T/F: S. vulgaris was previously (pre-ivermectin) the most important helminth of horses
TRUE
_____ and _____ from S. vulagris infections may have accounted for both fatal and nonfatal colic cases
verminous thrombi; emboli
what is the life cycle of S. vulgaris
- L3s ingested while grazing
- patent period of 6 months
- L4s penetrate intima, migrate, develop and enlarge of 4 months
- L4s molt to L5 and migrate into blood stream
- L5s form abscesses which rupture
- adult worms in lumen of cecum/colon
when is pathology apparent in S. vulgaris infections
caused by migrating L4s in the mesenteric arterial system
how is S. vulgaris diagnosed
- presents as peritonitis
- signs of colic, fever, etc.
- exploratory laparotomy
- non strangulating intestinal infarction
T/F: FEC can be helpful in S. vulgaris diagnosis
FALSE
how is S. vulgaris treated
- surgical correction (severe)
- deworm with larvicide 1-2x/year
describe the issue of S. vulgaris reemergence
dewormers are being underused
Oesophagostomum infect what species
ruminants and swine
describe the life cycle of Oesophagostomum
- L3s ingested while grazing
- PPP of 1-2 months
- L4s develop in gut wall
- return to lumen and develop to adults
what is the pathology of Oesophagostomum
- adults and older juveniles
- encysted L4s in sensitized host are the cause of pathology
- watery, dark D+
- pus-filled or caseous nodules in serosa of gut
T/F: dewormer resistance to Oesophagostomum is present in swine only
TRUE
how is Oesophagostomum targeted
- general pasture management
- in-feed dewormers for L3s
