Lecture 5 1/29/24 Flashcards
What are the general characteristics of the Strongylida subfamily Stryongyloidea?
-males with caudal copulatory bursa
-males and females with buccal capsule
-large, heavily sclerotized buccal capsule
-corona radiata/leaf crown of cutting teeth around mouth
What are the characteristics of subfamily Strongyloidea eggs?
-thin-shelled
-morula stage
What are the characteristics of subfamily Strongyloidea general life cycles?
-live in large intestine
-direct lifecycles
-species with both migratory and nonmigratory life cycles
What are the two subfamilies of importance for the Strongyloidea?
-Strongylinae
-Cyathostominae
What are the characteristics of Cyathostomes/small Strongyles species?
-DH is horses
-6-22 mm adult size
-PPP of 6-12 weeks
-eggs 70-100 x 40-50 um*
What are the charactersitics of Cyathostominae/small Strongyles life cycle?
-adults in cecum and colon
-direct life cycle
-non-migratory in body
-develop in nodules in mucosa
-arrest as early L3 in submucosal nodules
-can remain in nodules up to 2 years
-resume development with outside stimulus
What are the characteristics of Small Strongyle Disease/Larval Cyathostominosis?
-large numbers of worms in otherwise healthy horses
-occurs during prepatent period
-predisposition in young horses and those recently dewormed
-often seen in the fall
-death in 50% of cases
What is the infectious stage for Cyathostominae/small Strongyles?
L3
What clinical signs are seen with Small Strongyles Disease?
-diarrhea
-cachexia
-colic
-anorexia
-protein-losing enteropathy
-ventral edema
What leads to clinical signs in Small Strongyles Disease?
mass emergence of encysted larvae
What findings on a CBC can help indicate a small strongyles infection?
-neutrophilia
-anemia
-eosinophilia
What findings on a chemistry panel can help indicate a small strongyles infection?
-hypoalbuminemia
-hyperglobulinemia
-elevated total protein
How can ultrasound be used in diagnosing small strongyles infection?
it can reveal a thickened large intestinal mucosa
What are the large strongyles species of importance?
-Strongylus vulgaris
-Strongylus edentatus
-Strongylus equinus
What are the characteristics of Strongylus vulgaris?
-females 11-16 mm
-males 20-24 mm
-PPP of 6 months
What are the characteristics of Strongylus edentatus?
-females 23-35 mm
-males 33-44 mm
-PPP of 11 months
What are the characteristics of Strongylus equinus?
-females 26-35 mm
-males 35-50 mm
-PPP of 9 months
How does the life cycle of large strongyles differ from that of small strongyles?
-large strongyles have extensive larvae migration within the host before maturation
-in small strongyles, larvae go straight to the intestine and do not migrate
What are the steps of the Strongylus vulgaris life cycle?
-enters wall of distal small intestine, cecum, and ventral colon
-penetrates to submucosa and molts to L4
-L4 penetrates adjacent arterioles and migrates to anterior mesenteric artery
-L4s continue to grow and migrate through vessels
-return to small and large intestine carried by the blood
-occlude arteries, leading to inflammation and arterial wall destruction
-enter submucosa and encapsulate in nodule to molt into adult
-immature adults enter cecum and colon lumen and mature
What clinical signs are seen due to Strongylus vulgaris migration?
-peritonitis
-arteritis
-thrombosis
-embolism
-ischemia
-infarction
-verminous aneurysms
What is the clinical significance of Strongylus vulgaris?
-seen in young horses
-disease occurs during PPP
-pathology associated with larval stages
-most pathogenic of the large strongyles
What are the characteristics of Strongylus edentatus larval migration?
-larvae go to liver first
-from there, migrate through abdominal tissues
-return to colon
What are the characteristics of Strongylus equinus larval migration?
-larvae go to liver first
-migrate through abdomen, primarily pancreas
-return to colon
What are the pathologic characteristics of Strongylus equinus?
-causes pancreatic dysfunction
-associated with peritonitis
-liver pathology occurs
-extremely rare in US
What are the pathologic characteristics of Strongylus edentatus?
-associated with peritonitis
-liver pathology occurs
-very rare in US
How are equine strongyles species diagnosed?
-detection of eggs on fecal float
-ELISA testing to identify previous infection
What can fecal egg counts be useful for?
-monitoring drug effectiveness
-pasture contamination evaluation
-identification of high egg shedding animals
What is coproculture?
putting eggs in a warm, damp environment to promote hatching/culture and be able to differentiate Strongylus spp.
Which Strongylus species can be ID’d using PCR?
S. vulgaris
What are the characteristics of order Chabertiidae nodular worms?
-host are ruminants, swine, and primates
-live in large intestine
-larvae encapsulate in intestinal wall
What are the pathologic characteristics of order Chabertiidae?
-encapsulated larvae cause inflammation, diarrhea, and emaciation
-nodules can caseate and calcify
-clinical disease due to larvae, not adults
What are the characteristics of Chabertia spp.?
-aka large-mouthed bowel worm
-DH is ruminants
-females 17-20 mm
-males 13-14 mm
-PPP of 6-8 weeks
-large sub-globular buccal capsule
-corona radiata with small sawtooth elements
What are the characteristics of Oesophagostomum spp.?
-DH are cattle, sheep, goats, pigs, primates, rodents
-females 13-22 mm
-males 12-17 mm
-PPP of 40 days
-shallow buccal capsule
-corona radiata and cervical groove/collar present
What pathology is seen with Oesophagostomum spp.?
fibrotic nodules left behind by larvae
What are the characteristics of Syngamus spp.?
-aka gapeworm
-DH is birds
-direct life cycle
-earthworms as paratenic host
-females 5-40 mm
-males 2-6 mm
-eggs 80-110 x 40-50 um
-PPP of 2 weeks
-exception to large intestine rule for Strongyles
What are the characteristics of Syngamus trachea?
-male and female live in trachea in permanent copulation
-earthworms/mollusks/insects are paratenic hosts
-controlled by raising birds off soil
What are the clinical signs of Syngamus trachea in poultry?
-pneumonia
-hemorrhagic tracheitis
-mucus plugging air passages
-asphyxiation/blockage of air
What do Syngamus spp. eggs look like?
have double plugs like whipworm eggs
How do Syngamus spp. eggs get into the feces?
eggs are coughed up and swallowed
