Roundworms Flashcards
General morphology
- 1 mm-1 m
- Elongate, cylindrical, tapering at both ends
- Surface of transparent cuticle chitin
- Tubular digestive tract from mouth and buccal cavity, through oesophagus and intestine (built up of a single layer of cells) to the anus (in females) or cloaca.
- Males: usually smaller, with tesis, leding to vas deferens then to ejaculatory duct and cloaca, accessory copulatory structures at tail end: chitinous spicules (usually paired) and caudal alae/copulatory bursa
- Female: usually paired ovaries, oviduct, paired uteri, vagina opening by vulva
Heterakis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts
-H.gallinarum: domestic and guinea fowl, turkeys, pigeon, pheasant
-H.dispar: duck, goose
-H.isolonche: pheasant, wild birds - Morphology: 0.7-1,5cm long, white
- Predilection site: caecum, occ. LI+SI
- Life cycle: direct
- Clinical signs: not specific, heavy inf.: diarrhea, unthriftiness
- Faecal examination:
• Detection of eggs (65-80μm size, ellipsoidal, thick, parallel sided smooth-shell w. zygote) - flotation method
• eggs similar to A. galli, but smaller (<80 μm) and different in shape - Necroscopy findings: in heavy infections haemorrhages and thickening of the caecal mucosa, verrucous typhlitis with nodules
Strongylidiosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs:
- Examination method
- Necropsy findings
- Species and hosts: equines
•Large strongyles: Strongylus vulgaris, S.equinus, S.edentatus
•Small strongyles (‘cyathostomes’): e.g. Cyathostomum,
Triodontophorus, Cylicocyclus spp. - Morphology:
•Large strongyles: 2.5-5 cm long, greyish-red, developed large buccal capsule in its base w. 2 (S.v.) or 4 (S.eq.) or no (S.ed.) tooth-like projections
• small strongyles: 0.5-2 cm in length, white to dark red, smaller, ring shaped buccal capsule - Predilection site of adults: caecum and colon
- Life cycle: direct
- Clinical signs: inapparent, rarely diarrhoea, unthriftiness, anaemia etc.
- Examination method:
• detection of „strongyle-type” eggs (70-90 μm long, oval, thin-shelled, 8-16 cell stage) - flotation method
• species id. by specialized lab. on morphology of L3 obtained from faecal culture - Necroscopy findings: adults of large/small strongyles in caecum/colon
Oesophagostomum
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
Nodular worm
1. Species and hosts:
-Oe.dentatum+O.quadrispinulatum: pig, wild board
-Oe.radiatum: cattle, buffalo, wild large Ru
-Oe.venulosum: sheep, goat, wild small+large Ru
-Oe.colombianum: sheep, goat
2. Morphology: 1.2-5cm, white, thin, tapered head, shallow buccal capsule, filariform but wide cuticular cephalic vesicle at ant. end
3. Predilection site: caecum, colon
4. Life cycle: direct
5. Clinical signs: not common and typical (fever, inappetence, diarrhea, emaciation, anaemia, edema)
6. Exam. method: detection of “strongyle-type” eggs (70-80um, spherical, thin-shelled, morula) w. flotation
• Pig: eggs not disting. from Hyostrongylus rubidus eggs - fecal culture needed to diff. L3
• Ru: eggs not disting. from GI-nematodes
7. Necropsy findings:
• pig: necrotic-diphteroid or hemorrhagic enteritis
• Ru: cattharal colitis, chronic cases: oedema, anaemia, yellowish-green or >2cm long brownish-red purulent nodules (Ø nodules in Oe.venulosum)
Oxyuriosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
Pinworm
- Species and hosts: horse + donkey
- Oxyuris equi: common pinworm
- Probstmayria vivipara: minute pinworm - Morphology:
- O. equi: female 4-15cm/male 1-2cm, gray-white, gradual tapering towards tail, long and pointed tail
- P.vivipara: 0.2-0.3cm, long and filamentous tail - Predilection site: caecum, colon, rectum
- Life cycle: direct
- Clinical signs: perineal irritation, intense itching around anus, scaling of skin (“rat-tail”),
- grayish-yellow, gelatinous/dried scale-like masses of eggs around perineal skin
- female worms may be seen in fresh feces - Exam. method: rarely found on routine fecal flotation (40x90um, ovoid, yellow, asymmetrical, thick-shelled, operculated, morula)
- Necropsy findings: O.equi adults in colon/rectum
Trichuriosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
Whipworm
- Species and hosts
- T.vulpis: dog/fox, cat
- T.suis: pig
- T.ovis, T.globulosa, T.discolor, T.skrjabini: Ru
- T.leporis: rabbit, hare - Morphology: 3-8cm, white, ant.part tapered, post. part broad, female tail curved - male coiled
- Predilection site: caecum, colon
- Life cycle: direct
- Clinical signs: light inf. sympt., heavy inf. diarrhea, emaciation, anaemia, inappetence
- Exam. method: detection of eggs (40-80um, lemon-shaped, thick-shelled, operculated on both sides, yellowish-brown, with zygote - flotation method
- Necropsy findings: catarrhal-hemorrhagic typhlitis and colitis, hemorrhagic w. ulceration and formation of cropous-diphteric COLITIS
Flotation method
- Hyostrongylus rubidus - pig GI worm
- Amidostomum - goose gizzard worm
- Trichostrongylydiosis
- Ancylostoma, Uncinaria - Ca hookworm
- Bunostomum - Ru hookworm
- Strongyloides - dwarf worms
- Parascaris equorum
- Ascaris suum
- Ascaridia
- Toxocara, Toxoscaris
- Heterakis
- Strongylidiosis (adults only)
- Oesophagostomum
- Trichuriosis
- Syngamus trachea
- Metastrongylus - Pig lungworm
- Dictyocaulus arnfieldi
- Capillaria aerophila
Baermann technique
- Dictyocaulus viviparus + arnfieldi
- Crenosoma - Canine lungworm
- Angiostrongylus - Car lungworm
- Aelurostrongylus - Fe lungworm
No fecal examination possible
- Strongylosis (Ø eggs, but transrectal US or X-ray)
- Cyathostomes (Ø eggs, but transrectal US or X-ray)
- Oxyuris (rarely w. flotation)
- Osleris, Filaroides (less reliable, but endoscopy of trachea)
Has paratenic host
- Syngamus (earthworms, slugs, snails, beetles)
- Capillaria (earthworms)
Has intermediate host
- Metastrongylus (earthworms)
- Oslerus rostratus (snails, slugs)
- Crenosoma (molluscs)
- Angiostrongylus (snails, slugs)
- Aelurostrongylus (snails, slugs)
Host: Ru
a) Cattle
b) Sheep, goat
c) Deer
- Strongyloides papillosus: SI
- Toxocara vitulorum: cattle, buffalo, sheep, goat - SI
- Trichuris - whipworm: T.ovis, T,globulosa, T.discolor, T.skrjabini - caecum and colon
a) CATTLE: - Trichostrongylid:
• Abomasum: Haemonchus placei, Ostertagia ostertagi, Trichostrongylus axei
• SI: Cooperia punctata, C.oncophora, Nematodirus helvetianus - Bunostomum phlebotomum: SI
- Oesophagostomum radiatum: LI, ileum (+ buffalo, wild large Ru)
- Dictyocaulus viviparus (+deer, buffalo, camel): trachea+bronchi
b) Sheep, goat: - Trichostrongylid:
• Abomasum: H. contortus, Teladorsagia circumcinta, Tr.axei
• SI: Tr.colubriformis, C.oncophora, C.curticei, N. filicollis, N.spathiger, N.battus - Bunostomum phlebotomum: SI (+wild Ru)
- Oe. venulosum (+wild small+large Ru), Oe. colombianum: LI, ileum
- Dictyocaulus filaria: trachea+bronchi
c) Deer: - Dictyocaulus viviparus , D. filaria, D. eckerti: trachea+bronchi
Host: Equine
- Trichostrongylus axei: horse+donkey - stomach
- Strongyloides westeri - thred worms: horse, donkey - SI
- Parascaris equorum: horse, donkey - SI
- Strongylidiosis: Adults, colon, caecum
•Large strongyles: Strongylus vulgaris, S.equinus, S.edentatus
•Small strongyles (‘cyathostomes’): e.g. Cyathostomum,
Triodontophorus, Cylicocyclus spp. - Strongylosis: Larvea, colon, caecum, other
• S. vulgaris larvae: caecum, colon, A. mesenterica cranialis
• S. equinus larvae: colon, abd. cavity, liver, pancreas
• S. edentatus larvae: colon mucosa, V.portae, liver, subperitoneal haemorrhages - Oxyuris equi, Probstmayria vivipara - pinworm: Horse, donkey - LI
- Dictyocaulus arnfieldi: trachea+bronchi
Host: pig
- Hyostrongylus rubidus - red stomach worm
- Strongyloides ransomi - thred worms: SI
- Ascaris suum: pig, wild boar - SI
- Oesophagostomum dentatum, Oe. quadrispinulatum - nodular worm - caecum, colon
- Trichuris suis - whipworm - caecum, colon
- Metastrongylus apri, M. pudendotectus, M. salmi: pig - lungworm
Host: Carnivores
a) Dog
b) Cat
- Ancyclostoma braziliense: dogs, cats in tropics - SI
- Uncinaria stenocephala: dogs, cats, wild - SI
- Strongyloides stercoralis - thred worms: dog, fox, cat - SI
- Toxascaris leonina: dog, fox, cat - SI
- Trichuris vulpis - whipworm (fox, dog, cat) - caecum, colon
- Capillaria aerophila (fox, dog, cat) - lungworm
- Angiostrongylus vasorum (fox, dog, cat) - lungworm
a) Dogs: - Ancyclostoma caninum: SI
- Toxocara canis: SI
- Oslerus osleri dog, wild canids, Filaroides milksi, F. hirthi - lungworm
- Crenosoma vulpis - lungworm
b) Cat: - A. tubaeforme: SI
- T. cati - SI
- Oslerus rostratus - lungworm
- Aelurostrongylus abstrusus - lungworm
Host: rabbit and hare
- Trichuris leporis - whipworm
Host: birds (and which birds?)
- Heterakis: caecum, occ. S+LI
H.gallinarum: domestic and guinea fowls, turkey, pigeon, pheasant
H.dispar: duck, goose
H.isolonche: pheasant, wild birds - Syngamus trachea: domestic and guinea fowls, esp. chicks (<2-3m.), turkey, pheasant, patridge
Parasites found in stomach
- Hyostrongylus - pig
- Amidostomosis - gizzard of goose
- Trichostrongylus:
• Abomasum of cattle: H.placei, O.ostertagi, Tr.axei (stomach of horse+donkey too)
• Abomasum of sheep+goat: H.contortus, Teladorsagia circumcinta, Tr.axei - Ostertagia/Teladosargia
- Cooperia
- Nematoderus
Parasites found in small intestines
- Trichostrongylus:
• Cattle: C. punctata, C.oncophora, N.helvetianus
• Sheep+goat: Tr.colubriformis, C.oncophora, C.curticei, N. filicollis, N.spathiger, N.battus - Ancyclostoma caninum: dogs, wild
- A. tubaeforme: cats, wild
- A.braziliense: dogs, cats in tropics
- Uncinaria stenocephala: dogs, cats, wild
- Bunostomum phlebotomum: cattle
- B.trigonocephalum: sheep, goat, wild Ru
- Strongyloides - thred worms:
• pig: S. ransomi
• Ru, rabbit: S. papillosus
• horse, donkey: S. westeri
• dog, fox, cat: S.stercoralis, man (distinct strain of S.stercoralis) - Parascaris equorum: horse, donkey
- Toxocara vitulorum: cattle, buffalo, sheep, goat
- Toxocara canis, T. cati, Toxascaris leonina (dog, fox, cat)
- Ascaris suum: pig, wild boar
(- Ascaridia galli, A. columbae, A. dissimilis: birds intestines)
(Heterakis gallinarum, H. dispar, H. isolonche: birds occasionally, mainly caecum) - Oesophagostomum: ileum (+ LI)
• Oe. radiatum: cattle, buffalo, wild large Ru
• Oe. venulosum: sheep, goat, wild small+large Ru
• Oe. columbianum: sheep, goat
Parasites found in caecum
- Heterakis gallinarum, H. dispar, H. isolonche (+occ. S+LI)
- Strongylidiosis: Equine
•Large strongyles: Strongylus vulgaris, S.equinus, S.edentatus
•Small strongyles (‘cyathostomes’): e.g. Cyathostomum,
Triodontophorus, Cylicocyclus spp. - Strongylosis: Larvea, Equine
• S. vulgaris larvae: submucosa and wall of caecum and colon, A. mesenterica cranialis - Oesophagostomum
• Oe. dentatum, Oe. quadrispinulatum: pig, wild boar
• Oe. radiatum: cattle, buffalo, wild large Ru
• Oe. venulosum: sheep, goat, wild small+large Ru
• Oe. columbianum: sheep, goat - Oxyuris equi, Probstmayria vivipara: Horse, donkey
- Trichuris - whipworm
• T. vulpis: dog/fox, cat
• T. suis: pig
• T. ovis, T. globulosa, T. discolor, T. skrjabini: Ru
• T. leporis: rabbit, hare
Parasites found in colon
- Strongylidiosis: Adults, Equine
•Large strongyles: Strongylus vulgaris, S.equinus, S.edentatus
•Small strongyles (‘cyathostomes’): e.g. Cyathostomum,
Triodontophorus, Cylicocyclus spp. - Strongylosis: Larvea, Equine
• S. vulgaris: submucosa and wall of caecum and colon, A. mesenterica cranialis
• S. equinus: subserosa of colon, abd. cavity, liver, pancreas
• S. edentatus: colon mucosa, vena portae, liver, subperitoneal haemorrhages - Oesophagostomum - nodular worm
• Oe. dentatum, Oe. quadrispinulatum: pig, wild boar
• Oe. radiatum: cattle, buffalo, wild large Ru
• Oe. venulosum: sheep, goat, wild small+large Ru
• Oe. columbianum: sheep, goat - Oxyuris equi, Probstmayria vivipara: Horse, donkey
- Trichuris - whipworm
• T. vulpis: dog/fox, cat
• T. suis: pig
• T. ovis, T. globulosa, T. discolor, T. skrjabini: Ru
• T. leporis: rabbit, hare
Parasites found in liver
• Strongylosis equinus larvae, S. edentatus larvae
Parasites found in trachea
- Syngamus trachea - gapeworm: birds
- Dictyocaulus
• cattle, deer, buffalo, camel (D. viviparus)
• sheep, goat, moufflon, other wild small Ru (D. filaria)
• fallow deer (D. eckerti)
• horse, donkey (D. arnfieldi) - Oslerus osleri: canines
- Capillaria aerophila: fox, dog, cat
- Crenosoma vulpis: fox, dog
Parasites found in bronchi/bronchioli
- Dictyocaulus
• cattle, deer, buffalo, camel (D. viviparus)
• sheep, goat, moufflon, other wild small Ru (D. filaria)
• fallow deer (D. eckerti)
• horse, donkey (D. arnfieldi) - Metastrongylus apri, M. pudendotectus, M. salmi: pig
- Oslerus osleri, O.rostratus: dog, cat, wild
- Capillaria aerophila: fox, dog, cat
- Crenosoma vulpis: fox, dog (+bronchioli)
- Aelurostrongylus abstrusus (bronchioli): cat, wild cats
Parasites found in lung lobes
- Metastrongylus apri, M. pudendotectus, M. salmi: pig
• Oslerus rostratus: dog, cat, wild cat
• Filaroides milksi, F. hirthi: dog, wild dog - Capillaria aerophila: fox, dog, cat
- Aelurostrongylus abstrusus: cat, wild cats
Parasites in frontal sinus
- Capillaria aerophila: fox, dog, cat
Parasites in heart, pulmonary artery and its branches
Angiostrongylus vasorum: fox, dog and other canids, rarely cat
Major morphological differences
- Hyostrongylus: red, filariform oeso., bursa copul.
- Amidostomosis: red, shallow buccal capsule
- Trichostrongylus: male; spiculum + bursa copul.
- Haemonchus: female; red/white barber-pole+pied+valvular flap to cover vulva
- Ostertagia, Teladorsagia: divided spiculums w. holes at the end
- Trichostrongylus: has gabernaculum
- Cooperia: ring-like structure on neck + swollen area on spiculum + “shoe”-like structure on spiculum
- Nematodirus: ant. part much thinner than post. part. v.long spicules,
- Hookworms: Ancylostoma, Uncinaria, Bunostoma: large buccal capsule w. paired teeth - don´t need to distinguish
- Strongyloidosis: long, thin, GO in middle of female
- Parascaris: 20-40 cm, white
- Bovine toxocara: 15-30 cm, white
- Ascaridiosis: 15-40 cm, white
- Car toxocara: 3 lips, curly tail in male+spiculum, lateral wings ant.,
- Heterakis: pre-anal sucker
- Strongylidosis: large buccal capsules w. 2(S.v)/4(S.eq)/0 (S.ed) teeth, ant. part rounded, many gut cells
- Strongylosis: ring-shaped buccal capsule, few gut cells
- Oseophagostomosis: shallow buccal capsule, swollen veisicle (but still filariform), bursa copulatoris
- Chabertiosis: large buccal capsule, sometimes broken, Ø teeth
- Oxyuris: gradual tapering towards tail, long and pointed tail
- Probstmayria: long and filamentous tail
- Trichuris: whip-like, head is female: curved/male; curly (“hair”) and tail bigger and coiled, one spiculum
- Syngamus: permanent copulation, male large and shallow buccal capsule
- Dictyocaulus: Ø buccal capsule, just small opening, female has genital pore in midle, male; bursa cop.+spiculum
- Protostrongylus: Ø dist.
- Metastrongylus: 6 lips, male; long bursa cop.+spiculum, female; bulb on end
- Osleris/Filaroides: Ø bursa cop.
- Capillaris: cross section of bronchi?
- Crenosoma: striated surface of neck, bursa cop+spiculum
- Angiostrongylus: female; red/white barber-pole+pied, male has spiculum
- Aeulriostrongylus: very slender
Hyostrongylus
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: Hyostrongylus rubidus (red stomach worm) - pigs, wild boar, occasionally rabbit, guinea pig
- Morphology: 0.4-1.0 cm long, thin, reddish, w. small cephalic vesicle
- Predilection site: attached to gastric mucosa, embedded in catarrhal exudate
- Life cycle: direct
- Clinical signs: often asymptomatic, not specific (inappetence, anaemia, weight loss, agalactia, diarrhoea, vomitus)
- Faecal examination:
• Flotation („strongyle-type” eggs: 60-80 μm long, ovoid/elliptic, colourless, thin-shelled, 16-32 cell stage (4-8 in vomitus!)
• Diff. from Oesophagostomum spp.: L3 from faecal culture - Necroscopy findings:
- Hypertrophic, ulcerative acute gastritis
- Chronic catarrhal, croupous- diphteritic gastritis leading to excess production of tenacious mucus, ulceration
- Mucosa of the stomach is thickened, lenticular, flat nodules
- Tiny red worms can be recognized in the glass-like, tenacious mucus covering the gastric mucosa
Amidostomosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: A.anseris - gizzard worm disease of goslings, ducklings and young aquatic fowls
- Morphology: 1-2.5 cm, bright red, shallow “buccal capsule” - mouth opening
- Predilection site: under the horny (keratinoid) lining of gizzard, on mucosa, close to junction of proventriculus and gizzard
- Life cycle: direct
- Clinical signs: not specific, apathy, anaemia, emaciation, diarrhoea in heavily infected 1-2 month old goslings
- Exam. method: Flotation - 100 μm, ellipsoidal, thin-shelled, 32 cell or morula stage
- Necropsy findings: often loosened horny lining, dark-red folds or cream-like catarrhal inflammation and haemorrhages on mucosa of gizzard
Trichostrongylidiosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: GI-nematodes of Ruminants
• Abomasum of cattle: H.placei, O.ostertagi, Tr.axei (stomach of horse+donkey too)
• Abomasum of sheep+goat: H.contortus, Teladorsagia circumcinta, Tr.axei
• SI of cattle: C. punctata, C.oncophora, N.helvetianus
• SI of sheep+goat: Tr.colubriformis, C.oncophora, C.curticei, N. filicollis, N.spathiger, N.battus - Morphology
• Haemonchus: 1-3 cm long, females are pied w. “barber’s pole”
• Ostertagia, Teladorsagia (brown stomach worm): 1 cm long, reddish-brown, tiny cervical papillae
• Trichostrongylus (bankruptworm): <1 cm long, porus excretorius (notch) anteriorly, gabernaculum
• Cooperia: < 1 cm long, pinkish, ring-like stricture of neck
• Nematodirus (thread-necked worms): 1-2.5 cm long, the ant. half thinner, small striated cephalic vesicle, extremely long spicules, their tips are fused together and doubled bursal rays in the male - Predilection site: Abomasum/SI
- Life cycle: direct
- Clinical signs: not specific
• acute haemonchosis: anaemia, dark coloured faeces, submandibular oedema, weakness
• summer ostertagiosis: profuse, watery diarrhoea with putrid smell, dehydration, loss of appetite,
weight and production, weakness
• winter ostertagiosis: submand. oedema
• tricho., cooperia, nemato: severe, black, haemorrhagic diarrhoea - Exam. method: Flotation - ”trichostrongyle-type” eggs (60-110 μm long, thin- shelled in 8-16(32) cell stage; eggs of Nematodirus twice x size and at 4-8-cell stage)
- Necropsy findings:
• haemorrhagic gastritis (haemonchosis)
• hyperaemic abomasal- and SI-mucosa,
• tricho., cooperia, nemato: villous atrophy and erosion of mucosa
• nodules (ostertagiosis)
• worms in the abomasum and/or SI
Strongyloidosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: Thredworms/Dwarfworms
-S.ransomi: pig
-S.papillosus: Ru, rabbit
-S.westeri: horse, donkey
-S.stercoralis: dog, fox, cat, hu (distinct strain) - Morphology: 2-8 mm, slender, white, genital pore at middle of female
- Predilection site: SI
- Life cycle: direct
- Clinical signs: mild infections usually asymptomatic; heavy infections in:
• 2-4 weeks piglets: bloody diarrhoea, anaemia, emaciation, exsiccosis
• 1-3 months calves, 2-6 weeks lambs/kids: coughing, dyspnoe, fever, anorexia, diarrhoea, anaemia - Faecal exam.: Flotation - eggs (ellipsoidal, thin-shelled, very small: 40-50 μm, containing L1) (except Ca, Hu: ca. 300μm larvae pass w. faeces)
- Necroscopy: worms in of SI mucosa (at ca. 1 m distance from pylorus)
Parascariosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: Equine - Parascaris equorum
- Morphology: 20-40 cm in length rigid, whitish
- Predilection site: SI
- Life cycle: direct (ascaroid type)
- Clinical signs: mild infections are inapparent; in young, heavily infected foals coughing, nasal discharge, anorexia, dullness, sometimes colic, dull coat, weight loss, occ. nervous signs, diarrhea; spontaneous discharge of worms in the faeces
- Faecal exam.: Flotation - eggs (90-100 μm sized, almost spherical, yellowish-brown, thick-shelled with pitted surface; atypical eggs appear as smooth- and thick-walled, colourless, translucid)
- Necroscopy: catarrhal enteritis, occ. invagination, mechanical occlusion of SI, rupture of intestinal wall, peritonitis; hemorrhages, inflammatory foci, nodules containing dead larvae in liver+lungs
Bovine toxocarosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: Toxocara vitulorum - cattle, buffalo, occ. sheep, goat
- Morphology: 15-30 cm long, white, slightly transparent
- Predilection site: SI
- Life cycle: direct (toxocaroid type)
- Clinical signs: in young calves (<4-5 month) changing appetite, decreased growth-rate, abdominal spasm, diarrhea, strong butyric or aceton-like odour, spontaneous discharge of worms in faeces
- Faecal exam: Flotation method in less than 4 month old calves - eggs (70-90 μm sized, brownish, thick- shelled with outer pitted coat)
- Necroscopy findings: catarrhal enteritis, acetone smelling meat
Porcine ascariosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: Ascarosis suum - pig, wild boar
- Morphology: 15-40 cm long, rigid, white
- Predilection site: SI
- Life cycle: direct (ascaroid type) - PP: 2 months!
- Clinical signs: mild infections are inapparent; in young, heavily infected animals coughing, dyspnoea, anaemia, anorexia, spontaneous discharge of worms in faeces
- Faecal exam: Flotation - eggs (50-70 μm sized, ovoid, brownish, thick-shelled which is irregularly mamillated) (false-pos. due to coprophagy)
- Necroscopy findings: catarrhal enteritis, roundworms in the gut, cloudy whitish spots („milk spots)” on surface of liver, haemorrhages in lung, pneumonia
Ascaridiosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts:
- A.galli: domestic and guinea fowl, turkey, duck, game birds
- A.columbae: chicken
- A.dissimilis: turkey - Morphology: 5-12 cm (A. galli), 3-7 cm long (A. columbae, A. dissimilis)
- Predilection site: SI
- Life cycle: direct (ascaridioid type)
- Clinical signs: moderate infections freq. inapparent, heavier inf: (mainly 2-3 months chickens with predisposing factors) dull feather-coat, curtailment of food, catarrhal enteritis, occ. intestinal occlusion, decreased egg prod., nervous signs
- Faecal exam: Flotation - eggs (90 μm sized, ellipsoidal, colourless, with smooth thick- shelled) (similar to Heterakis eggs, but bigger and sides are not parallel)
- Necroscopy findings: catarrhal-haemorrhagic-croupous enteritis
Toxocarosis, Toxoscarosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: carnivores
- T.canis: dogs, fox
- T.cati: cats
- Toxoscaris leonina: dogs, fox, cats - Morphology: 10-18 cm (T. canis), 3-10 cm (T. cati), 6-10 cm (T. leonina) long, has 3 lips, wide lateral wings at head, male has spiculum+curly tail
- Predilection site: SI
- Life cycle: direct (T. canis is ascaroid <1 month of age if infection prenatal or with egg containing L3; toxocaroid >4 months) (PE-2 of T. cati is ascaroid, toxocaroid) (PE-2 of T. leonina is ascaridioid)
- Clinical signs:
- mild infections: intermittent diarrhoea, changing appetite, pot-belly, anaemia, loss of weight, dull coat
- severe infection (puppies, kittens): coughing, changing appetite, dull coat, extended and sensitive belly (pot-belly), diarrhoea, vomitus (worms in it), nervous signs, epileptoid attacks, etc., spontaneous discharge of worms in the faeces - Exam. method: Flotation - eggs (T. canis: 75-90 μm sized, subglobular, brownish with thick, pitted shell, T. cati: 65-75 μm in size, subspherical, brownish, T. leonina: 70-85 μm in size, subspherical-oval, light, colourled, surface of eggshell is smooth, the zygote does not fill it)
- Necropsy findings: SI packed with worms, enteritis, obturation, invagination, haemorrhages and inflammation in the lungs; adults of Toxocara and Toxascaris are grossly indistinguishable
Life cycle types
- ascaroid type: small intestine-liver-lungs-trachea-pharynx-small intestine
- toxocaroid type: small intestine-liver-lungs-blood circulation (somatic migration, hypobiosis)
- ascaridioid type: moults in the mucosa of the small intestine (histotropic phase), mature in lumen
Syngamus
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: Syngamus trachea - Gapeworm disease - domestic fowl and game birds, esp. imp. in chicks (younger than 2-3 m.), turkey, pheasant and partridge
- Morphology: female (0.5-3 cm long, reddish) and male (0.5 cm long, whitish with large and shallow buccal capsule) live in permanent copulation forming a Y-shape
- Predilection site: trachea
- Life cycle: direct, but paratenic hosts: e.g. earthworms, slugs, snails, beetles
- Clinical signs: head shaking, sneezing, dyspnoea (gasping for air), asphyxia or suffocation; subscutaneous emphysema may occur along neck of 3-4 weeks old chick; worms may be seen in trachea of living birds
- Exam. method: Flotation - eggs 70-100 μm long, ellipsoidal, thin-shelled, operculum at both ends, 8-16-cell stage
- Necropsy findings: worm pairs, granulomas in the trachea, tracheitis with excess of bloody, foamy mucus; petechiae, haemorrhages, edema, vicariant emphysema, bronchopneumonia in the lungs
Dictyocaulosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts:
-D.viviparus: cattle, deer, buffalo, camel
-D.filaria: sheep, goat, mouflon, small wild animals
-D.eckerti: deer
-D.arnfieldi: horses, donkeys - Morphology: 3-8 cm long, slender, white worms, genital pore at the middle of the female
- Predilection site: lumen of bronchi and trachea
- Life cycle: direct
- Clinical signs: from late summer in young, grazing
animals in cattle and small ruminants:
• prepatent phase: tachypnoea, dyspnoea, dry coughing
• patent phase: fever, resp. distress, tachypnoea, dyspnoea, ‘air-hunger’ position (head and neck outstretched), deep harsh (dry to moist) cough, anorexia, loss of weight, emaciation, cachexia
in horse and donkey:
• frequently inapparent in foals, however, coughing, nasal discharge, resp. distress due to massive infections - Exam. method: L1 with Baermann technique - except in D.filaria: differentiation from protostrongylid L1
-In D.arnfieldi also flotation - eggs (100um, ellipsoidal, thin-shelled and w. L1) - Necropsy findings:
in cattle and small ruminants:
• prepatent phase: pulmonary edema, alveolitis, bronchiolitis, bronchitis, detection of larvae from small pieces of lungs
• patent phase: worms can be seen in the opened airways, chronic bronchitis and peribronchitis; worms and abundant purulent mucus plug the bronchial lumen, interstitial emphysema (dark-red atelectatic and pale emphysematic areas), peribronchial fibrosis, purulent secondary inflammation in horse and donkey
• in the caudal lung lobes raised, circumscribed areas of inflated tissue, central, bronchus with mucopurulent exudate, hyperplastic epithelium
Metastrongylidiosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: Pig lungworm: wild boar, pig, guinea pig
-Metastrongylus apri
-M. pudendotectus
-M. salmi - Morphology: 1.5-5.5 cm long, greyish-white
- Predilection sites: in the lumen of the bronchi, mainly in the diaphragmatic lobe of the lung
- Life cycle: indirect (intermediate hosts: earthworms)
Hosts: wild boar, pig, guinea pig - Clinical signs: not typical, in young pig (coughing, dyspnoea, nasal discharge, fever, anorexia)
- Faecal exam: Flotation - eggs (5-9 weeks after infection (about 50-60 μm sized, ellipsoidal, rough- and thick-shelled, containing L1)
- Necroscopy: lesions in diaphragmatic lobes, formation of small, greyish, consolidated nodules, muco-purulent bronchitis, compact areas of inflammation and soft areas of emphysema
Protostrongylidosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: Nodular lungworm in sheep and goat:
-Protostrongylus rufescens
-Cystocaulus ocreatus
-Muellerius capillaris
-Neostrongylus linearis - Morphology: all are thin, hair-like worms, 0.5-3 cm in length, colourless except P.rufescens; brown and Cystocaulus; dark brown
- Predilection site:
-P.rufescens: small bronchi
-The others: lung parenchyma - Life cycle: indirect, PP: 5-6 weeks, IM hosts (terrestrial
snails, slugs) - Clinical signs:
• prevalence increases with age, may reach 100% in sheep and goats >3 years
• worms in small bronchioli - inflammation of the terminal air passages and lobular pneumonia
• usually chronic and may lead to spontaneous recovery
Clinical signs: coughing, anorexia, retarded development, depressed production, anaemia - Examination method: Disease history and detection of L1 - umbrella rod like appearence
- Necropsy findings:
(1) brood nodules: cone-shaped, granuloma-like areas of affected lung tissue, which contain sexually active worms and masses of eggs and larvae; usually in diaphragmatic lobe
(2) wormknots: glass pinhead-shaped, mostly subpleural, gray (Muellerius) or dark-brown to black (Cystocaulus) cysts which contain sexually inactive, viable, adult worms only
Oslerosis, Filaroidosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: Lungworms in Car
• O. osleri: dog, wild canids
• O. rostratus: cats and wild felids
• Filaroides milksi, F. hirthi: dog, wild canids - Morphology
• O. osleri: small, pale worms, 0.5 to 1.5 cm
• O. rostratus: male 3-4 cm, female 5-6 cm long, slender
• Filaroides milksi, F. hirthi: 0.5-1 cm long, slender - Predilection sites:
• O. osleri: fibrous nodules on tracheal mucosa at the region of bifurcation and in the adjacent bronchi
• O. rostratus: sub-mucosa of bronci or in lung parechyma
• F. milksi, F. hirthi: lung parenchyma - Life cycle: direct; O. rostratus indirect (intermediate hosts snails or slugs)
- Clinical signs: usually remains inapparent; dry, paroxysmal coughing, respiratory distress, loss of appetite
- Faecal examination: detection of L1 is less reliable - endoscopy of the trachea in anaesthesia
- Necroscopy findings: chronic tracheo-bronchitis, characteristic nodular lesions at the region of bifurcation (O. osleri)
Capillariosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: Capillaria aerophila - fox, occ. dog, cat
- Morphology: 2.0-3.0 cm long, whitish and filamentous
- Predilection sites: in the mucosa of the bronchi, trachea/nasal passages, frontal sinuses
- Life cycle: direct (paratenic hosts: earthworms)
- Clinical signs: usually remains inapparent; coughing
- Faecal exam.: Flotation - detection of zygote - containing eggs (60-75 μm in length, barrel- shaped, asymmetry of bipolar plugs with absence of thickening at the basis)
- Necroscopy findings: finding the worms and/or detecting of eggs from the tracheal fluids
Crenosomosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: Crenosoma vulpis - fox, occ. dog and other canids
- Morphology: 0.5-1.5 cm long
- Predilection site: trachea, bronchi, bronchioli
- Life cycle: indirect (intermediate hosts: molluscs)
- Clinical signs: usually remains inapparent; coughing, sneezing, nasal discharge
- Faecal exam: detection of L1 with Baermann technique
- Necroscopy findings: rhino-tracheitis, bronchitis
Angiostrongylosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Species and hosts: Angiostrongylus vasorum - French heartworm - fox, occasionally dog and other canids, rarely cat
- Morphology: 1.4-2.5 cm long pied, white ovaries being spirally wound around the red intestine
- Predilection site: right ventricle, pulmonary artery and its branches
- Life cycle: indirect (intermediate hosts: snails, slugs)
- Clinical signs:
• respiratory signs (coughing, dyspnea, tachypnea)
• petechiae, ecchymoses, scleral hemorrhage, sublingual hemorrhage, hematomas
• neurologic signs ranging from seizures, circling, ataxia, to paresis
• ocular signs - Exam:
-Baermann technique - detection of L1 (310-400 μm in length with a characteristic kinked tail and a dorsal spine and notch)
-Detection of antigen/antibody: ELISA, western blot technique
-Diagnostic imaging: radiography, CT, MR - Necroscopy findings: rhino-tracheitis, bronchitis, endarteritis, endocarditis, pulmonary thromboangiitis, hemoabdomen, hemothorax; granulomatous interstitial pneumonia with thrombosis, fibrosis, adult worms in blood vessels and eggs/larvae in the pulmonary arterioles and capillaries
Aelurostrongylosis
- Species and hosts
- Morphology
- Predilection site
- Life cycle
- Clinical signs
- Examination method
- Necropsy findings
- Aelurostrongylus abstrusus - lungworm in cat, wild felids
- Morphology: 0.5-1.0 cm long, very slender worms
- Predilection site: bronchioli and lung parenchyma
- Life cycle: indirect (intermediate hosts: snails, slugs)
- Clinical signs: not specific, openmouthed abdominal breathing, dyspnea, intense coughing, sneezing, muco-purulent discharge
- Faecal examination: detection of L1 with Baermann technique
- Necroscopy findings:
• rhino-tracheitis, bronchitis
• in the lung parenchyma multiple small, greyish, translucid foci or bigger consolidated granulomas, muscular hypertrophy and hyperplasia
• eggs and L1 in squeeze preparation from the cut surface of the lung
• in heavy infection
Which are zoonotic?
- Oesophagostomum
Which eggs are strongyle-type?
Thin-shelled, ovoid/elliptic, colourless, morula stage – Flotation
- Hyostrongylus
- Amidostomum
- Strongylidiosis
- Oesophagostomum
- Hookworms: Ancylostoma, Uncinaria, Bunostomum
Eggs with thick shell
-Parascaris: yellowish-brown, pitted and sticky surface, Z inside
-Avian ascarosidiosis: ellipsoidal, colourless, smooth and thick-shelled
similar to Heterakis but bigger
-Heterakis: ellipsoidal, parallel-sided smooth, with Z
-Ascariosis suum: ovoid, brown, outer irregularly mamillated surface and Z inside
-Toxocara, Toxoscara:
o T.vitulorum subglobular, brown, outer pitted surface – Flotation - similar to T.cati and T.canis
o T. canis: subglobular, brownish, pitted shell
o T. cati: 65-75 μm, subspherical, brownish
o T. leonina: 70-85 μm, subspherical-oval, light, colourled, smooth surface, zygote does not fill the egg!
-Oxyuris: ovoid, yellow, slightly flattened on one side, thick-shelled, operculated on one side, morula stage
-Trichuris: lemon-shaped, yellow, operculated on both sides, similar to Capillaria but darker colour,
-Capillaria: barrel-shaped, asymmetry of bipolar plugs, w. zygote
Trichostrongyle-type eggs
60-110um, thin-shelled, 8-16 morula stage – Flotation
-Nematodirus spp. twice the size and 4-8 blastomer stage