Nematodes 1 Flashcards
sexual dimorphism
males are smaller and have an accessory copulatory structure
digestive tract
from mouth and buccal cavity through oesophagus and intestine to anus or cloaca
cell layers of intestine
single layer of cells
female organs
paired ovaries
oviduct
paired uteri
vagina opening by vulva
male organs
testis
vas deferens
ejaculatory duct
cloaca
accessory genitals
weak developed caudal cuticular alae
well developed copulatory bursa
what larval stage is infective
L3
life cycle
either direct or indirect
another name for strongyloidosis
dwarf worms
causes of strongyloidosis
strongyloides ransomi
s. papillosus
s. westeri
s. stercoralis
morphology of strongyloides
2-8mm long
slender
white
genital pore at the middle of the female
predilection sites of strongyloides
prox third part of small intestine
- extraintestinal migration
homogonic development
parasitic cycle with unfavourable external conditions
in young animals
Egg –> L1 –> L2, L3 —> infection —> parasitic adult
what is autoinfection
L3 wont be shed and immediately infects the host
life cycle of strongyloidosis
direct
heterogonic development
a parasitic cycle and free libing reproductive cycles in favourable external conditions
older animals
Egg –> L1, L2, L3 –> free living in males and females —> egg –> L1, L2, L3 –> parasitic adult
s. ransomi host
pig
s. papillosus host
ruminant
rabbit
s. westeri host
horse
donkey
s. stercoralis host
dog
fox
cat
man
clinical signs of strongyloides in 2-4 weeks old piglets =
bloody diarrhoea, anaemia, emaciation, exsiccosis
clinical signs of strongyloides 1-3month old calf =
coughing, dysponea, fever, anorexia, diarrhoea, anaemia
faecal examination of strongyloides
flotation
eggs of strongyloides
ellipsoidal
thin shelled
very small
40-50 um
containing a morula or L1
s. ransomi infection
larval development arrested for a long time therefore mmigrate to the mammary gland and infection is via colostrum and lactogenic
s. papillosus infection
percutan
s. westeri infection
colostal & lactogenic infection
s. stercoralis infection
autoinfection and percutan via rectum
necroscopy of strongyloides
in mucosa or the mucosal scrapings taken from the mucosa of the small intestine - 1m from pylorus
autoinfection of strongyloides
when L3 wont be shed and it will immediately infect the host
causes of strongylidosis
adults of large and small strongyles
small strongyles
cyathostomum
triodontophorus
cylicocyclus
large strongyles
stryongylus vulgaris
s. equinus
s. edentates
s. asini
large strongyles morphology
2.5-5cm long
greyish red
developed large buccal capsule in its base
tooth like projections
number of tooth like projections in s. vulgaris
2
number of tooth like projections in s. equinus
4
number of tooth like projections in s. edentatus
0
small strongyles morphology
0.5 - 2cm in length
white to dark red
ring shaped buccal capsule
predilection site of strongyles
caecum or colon
life cycle of strongyles
direct
prepatent period of s. vulgaris
6 months
prepatent period of s. equinus
9 months
prepatent period of s. edentates
11months
host of strongyles
equines
s. equinus infection route
L3 –> large intestine –> peritoneal cavity –> liver –>pancreas —>lumen of large intestine –>
thrombus formation in mesenteric artery
clinical signs of strongyles
inapparent
rarely diarrhoea
unthriftness
anaemia
faecal exam of strongyles
flotation
strongyles eggs
90um long
oval
thin shelled
length of s. vulgaris
1020um
length of s. edentatus
790um
length of s. equinus
980um
length of small strongyles
800um
body: tail of s. vulgaris
2.5: 1
body: tail of s. edentatus
2: 1
body: tail of s. equinus
2:1
body: tail of small strongyles
1.5:1
no. of gut cells of s. vulgaris
32
no. of gut cells of s. edentatus
20
no. of gut cells of s. equinus
16
no. of gut cells of small strongyles
8
characteristic of s. vulgaris
stumpy short
characteristic of s. edentatus
slender medium
characteristic of s. equinus
slender medium
characteristic of small strongyles
stumpy medium
necroscopy findings of strongyles
adults in caecum and colon
cause of strongylosis
infection of extraintestinal migrating larvae of large strongyles
predilection site of s. vulgaris larva
submucosa and wall of caecum and colon, a. mesenterica cranialis
predilection site of s. equinus larva
subserosa of colon
abdominal cavity
liver
pancrease
predilection site of s. edentatus larva
colon mucosa
vena portae
liver
sub peritoneal haemorrhages
clinical signs of strongylosis
unthriftness in foals
anaemia
colic
intermittent lameness
faecal exam of stronglosis
no eggs
necroscopy findings of s. vulgaris
in the trunk of the a. mesesnteric cranialis
inflammation of the arterial wall
formation of cauliflower like thrombus
colic
strangulation
ileus
aneurysms
abscesses
infact
necroscopy findings of s. equinus
haemorrhagic tracts
rarely hepatits
pancreastits
necroscopy findings of s. edenatus
liver and sub peritoneal haemorrhages
subserosa haematoma
what cyathostominosis
small strongyles larva in mucosa of large intestine
cause of cyathostominosis
large numbers of small strongyle larvae of cyathostomum spp in mucosa of the large intestine
treatment of cyathostominosis
moxidectin
fenbendazole
clinical signs of cyathostominosis
inapparent
rarely diarrhoea
colic
rapid weight loss
faecal examination of cyathostominosis
no eggs
necroscopy of cyathostominosis
catarrhal haemorrhagic enteritis
large number of brihgt red
L4, L5 in diarrhoeic faeces
L4 in mucosa
another name for nodular worm disease
oesophogostomosis
cause of oesophogostomosis
oesophagostomum denatum
oe. radiatum
oe. venulosum
oe. columbianum
oe. quadrispinulatum
charbertia ovina
morphology of oesophagostomum
1-2.5cm in length
thin
white worms with tapered head
shallow buccal cavity
inflated cuticular cephalic vesicle at anterior end
predilection site of oesophagostomum
caecum
colon
ileum in Ru
life cycle of oesophagostomum
direct
hosts of oe. denatum
pig
wild boar
hosts of oe. quadrispinulatum
pig
wild boar
hosts of oe. radiatum
cattle
buffalo
wild large ru
hosts of oe. venulosum
sheep
goat
wild small and large ru
hosts of oe. columbianum
sheep
goat
clinical signs of oesophagostomum
not common
fever
inappetence
diarrhoea
anaemia
oedema
emaciation
faecal exam of oesophagostomum
flotation
eggs of oesophagostomum in pigs
eggs arent distuingishable
eggs of oesophagostomum in ru
eggs not distinguishable from gi nematodes
necroscopy of oesophagostomum in pig
necrotic diphtheroid or haemorrhagic enteritis
necroscopy of oesophagostomum in ru
catarrhal colitis
oedema
anaemia
yellowish -green or up to 2cm sized brownish red purulent
no nodules in which oesophagostomum
oe. venulosum
cause of charbertiosis
charbertia ovina
another name for charbertiosis
large mouthed bowel worm
morphology of charbertiosis
large buccal capsule
strognyle type egg
direct life cycle
hypobiosis L4