Spiruroids Flashcards
Spirurida features
2 lateral lips, muscular oesohpagus with posterior glandular section, indirect LC, eggs with L1 or L1 viviparous
Split into which groups?
Filarid and non-filarid worms
Horse spirurids?
Draschia + Habronema
Lifecycle of Habronema and Draschia?
Which horse spirurids have musca as their IH vector?
Draschia megastoma
Habronema muscae
Lesions caused by Draschia megastoma?
Chronic eosinophilic granulomatous nodules and ulcers.
- may cause obstruction if near the pyloric opening
Which horse spirurid has Stomoxys as their IH?
Habronema microstoma
Gastric lesions of Habronema?
No nodules
small ulcerations, catarrhal gstritis (hyperplasia/hypertrophy of the mucus secreting cells)
Habronemiosis?
Multiple abcesses filled with necrotic debris containing part of the nematode larvae + eosinophilic inflammation around the lesioin.
What are these gorse spirurids?
L - Draschia megastoma
R - Habronema spp.
What solution for a faeces or gastric lavage floatation of spirurid eggs?
They have heavier eggs so use SG > 1.2 (salt and glucose)
NB: eggs may not shed if the adult is in a nodule
methods to diagnose spirurids
Cutaneous lesion biopsy
faecal float
Gastric lavage float
Drug treatment of Habronema
Adults: oxfendazol, moxidectin
Treatment of cutaneous lesions of habronemiosis (L3)
- ivermectin, abamectin, moxidectin
- surgical debridement, cryotherapy, corticosteroids + MLs
Other management for horses?
Control the vector
- dispose and compost manure, IGRs
- Face and eye masks, fans + fly screens in stables
Stomach worms of dogs and cats
Spirocerca lupi
Physaloptera praeputialis
Cylicospirura felineus, C. ubequalis
Gnathostoma spinigerum
Lifecycle of Spirocerca lupi
Pathogenesis and clinical signs of Spirocerca lupi
- common in tropical/subtropical regions
- sudden death due to haemothorax caused by ruptured aortic aneurism
- Granuloma may become neoplastic -> fibrosarcoma
- regurgitation, vomiting, weight loss
Diagnosis of Spirocerca lupi
- There may be no eggs n the faeces if no fistula in to lumen
- eggs are heavy
- endoscopy
- radiography
Treatment of Spirocerca lupi
- moxidectin for prophylactic use
- off label use of doramectin, moxidectin and milbemyin up to 6 months
- surgical removal of sarcoma
- Aid feeding to avoid mega oesophagus
- disallow scavaging/free roaming
Features of Cyclospirura felineus
Arthropod is beetle
common in feral cats
-> cysts with 1-40 worms
Features of Physaloptera praeeputialis
- Beetles, cockroaches + PH (lizard)
- small teeth cause ulcers on mucosa
- catarrhal gastritis +/- melena
Lifecycle of Gnathostoma
Gnathostoma pathogenesis and clinical signs
(feral cats and dogs)
- adults embedded in submucosal gastric nodules with tract leading to gastric lumen
- subclinical or gastritis, vomiting, anorexia
- peritonitis - perforated gastric wall
Diagnosis of Gnathostoma
- uni plugged eggs on faecal float
- adults 2-3cm with hooked cephalic bulb
How to treat Gnathostoma?
Ivermectin?
Gnathostamiasis in humans
- Fish born zoonosis
- L3 penetrate stomach and undergo larva migrans
- highly pruritic sub cutaneous swellings
Spirurid of pigs
Gnathostoma hispidum
Ascarops strongylina
Physocephalus sexalatus
What are these pig spirurids?
L - Ascarops (spiral rings)
R - Physocephalus (annular rings)
What causes these eye lesions?
Thalezia spp
What causes these lesions in cattle?
- non pathogenic
Gonylonema pulchrum (L - oesophagus)
Gonylonema verrucosum (rumen)
Spirurids of birds
Gonylonema spp (crop; IH cockroach)
Acuaria spp Tetrameres spp (stomach worms; IH grasshoppers, bettles)
Oxyspirura mansoni (conjunctival sac; IH cockroach)
Effects of Acuaria (Dispharyx) + Tetrameres
Larvae burrow under gastric mucosa and koilin of gizzard -> inflammation -> can’t grind food well -> vomiting and anorexia
Adults; hypertrophy, fibrous nodular growths in proventriculus, vomiting, anorexia
