GI Flashcards
In which breed of sheep is there an autosomally recessive congential holoprosencephaly? What does this look like?
Border Leicester. Cyclops
How does Veratrum californium exposure cause congenital orpharyngeal abnormalities?
Interferes with Sonic Hedgehog signalling
Which breed of sheep has an inherited porphyrinism? What oropharyngeal signs does this cause?
German Blackhead. Grey mucosae and discoloured teeth.
List risk factors for incisor loss (3).
Sandy soils. Acid soil. Oral dysbiosis.
In what age of sheep have odeontogenic cysts been reported?
2-4 years old.
What signs are seen on histopathology of wattle cysts. Are they clinically significant?
Staritified squanmous epithelium with mature hair follicles. Not significant.
Which bacteria is associated with necrotic stomatitis in lambs? Name a risk factor.
Fusobacterium necrophorum. Poor milk replacer/teat hygeine.
Which bacteria is associated with oral/facial abscesses. Name a risk factor.
Actinobacillus lignieresii. Thorny feed.
Which virus causes orf?
Parapox
How long do clinical orf lesions persist?
3-6 weeks
How does orf predispose to mastitis? How else does it suppress the host immune system?
Reduction in mammary lymphoid follice size. Produces viral-IL-10 and chemokine binding protein.
How soon to lambing can orf virus scarification be performed
> 7 weeks
Is orf virus host species specific?
No, but caprine and ovine strains exist (with reduced cross-immunity between them).
Which bacteria has been assocaited with high prevalence (c.30%) of osteomyelitis of the jaw in some flocks? Name a risk factor.
Pseudomonas aeruginosa. Harsh feed.
How can clover cause ptyalism? Name the toxin
Infection with Rhizoctonia leguminicola. Slaframine.
How can salivary mucocoeles be corrected? Why is the drainage location important?
Cannulation or marsupialisation. Bicarbonate lost if not draining into oropharynx.
How should the two layers of a rumenostomy be sutured?
Serosa to muscle, muscosa to skin.
Which protozoal parasite has been associated with megaoesophagus?
Sarcocystis
In which species have congenital oesophageal divericula been reported?
Goats
Name two forage plants associated with frothy bloat. Why are they risky? Why are trefoil and sainfoin less risky?
Alfalfa, clover. Rich in soluble proteins. Tannins reduce foam formation.
How soon after acute grain intake will signs of acidosis be seen?
12-36h
What rumen pH is acidotic?
<5.5
How long would methylene blue reduction tkae in a a case of rumenal acidosis?
> 9mins
Which gram stain group predominate in an acidotic rumen. How does this affect clincial signs?
Gram positive predominate. These produce less thiamine and more thiamiases. Death of gram negatives releses endotoxin.
What is the maxmimum wieght of concetrate that should be fed to a small ruminant in a single feed?
500g
What trough space do lowland ewes need for concentrate?
50cm/ewe
What fibre to starch ratio is recommended in diary goats?
1.43:1
What is the risk of feeding rumen buffers to small ruminants?
Counteract urinary acidiers
Name four bacteria that can cause abomasitis.
Clostridium sordelli. C. ventriculi. C. septicum (braxy - older animals in winter). Sarcina spp.
How do Sarcina spp. appear on cytology?
Gram positive cuboidal packets.
What age of animals are affected by watery mouth?
<72h
How much colostrum should neonates receive?
50ml/kg in first 4h, 200ml/kg in first 24h
How does neontal physiology allow watery mouth? How do bacteria exploit it?
Pinocytosis for absorption of large molecules allows bacterial uptake. Aerobactin-mediated iron transport system expands this.
Which group of rotavirus can cause neonatal diarrhoea? What age is it seen? How is it identified?
Group B. <2 weeks. Chromatographic lateral flow device or virus isolation.
What age of lambs/kids suffer from ETEC diarrhoea? What antigens are used for identification? Name two other causative E coli.
<10 days (often <5d). Fimbrial antigens K99 and F41. STEC and EPEC.
Describe the pathology seen in C. perfringens type A & C infection. What other syndrome can type A cause
Haemorrhagic enterotoxaemia with necrotic foci and ulceration. Yellow Lamb disease (haemolysis)
What bacteria causes lamb dysentery? What toxins does it produce? Why is infection only seen in neonates?
C. perfringens type B. Produces αβε toxins - but mostly β which cuases the intestinal pthology. β-toxin is degraded by trypsin but this process is inhibited by presence of colostrum (to protect antibodies from digestion).
Name 4 Saomonella enterica serovars associated with diarrhoea. What other clinical sign is often seen. What changes are seen in bloodwork?
Enterica, Arizonae, Dublin, Tymphimurium. Fever. Leukopaenia or leukocytosis.
How long does it take Cryptospridium oocysts to become infectious after passing? Name three treatment options? Are they effective?
They are immediately infective (sporulate in gut). Halofuginone (reduce shedding and death rate). In-milk/feed deccoquinate or paramomycin (reduce shedding only).
Name the two most pathogenic coccidia in sheep
Eimeria crandallis and Eimeria ovionoidalis.
What pathology does Eimeria bakuensis cause?
Localised polyps.
Name the five most pathogenic coccidia in goats
Eimeria ninakohlyakimovae, E. caprina, E. christenseni, E. hirci. E. arloingi
What temperature limits can cocciian oocysts survive? What other two environmental variables affect survival?
-30C min 63C max. Strong sunlight and dessication kill.
In coccidiosis how many rounds of schizogony occur before gametogenesis? How long after infection is peak excretion?
2 rounds. 2-4 weeks p.i. (often aged c.6 weeks)
Which is more effective against clinical coccidiosis, Diclazuril or Toltrazuril? Is decoquinate feeding helpful?
Toltrazuril (greater efficacy and duration). Feeding to lambs can act as preventative but feeding to ewes has minimal impact on lamb infections.
What age is campylobacter diarrhoea seen?
2 weeks +
What age is intestinal giradiasis seen?
2-4 weeks
The cause of terminal ileitis is not known, but name two pathogens it is associated with
Campylobacter, Border Disease Virus
What modification must be made to culture media to grow S-type Mycobacterium avium paratuberculosis
Removal of pyruvate
Infeciton with C-type and S-type MAP are assocaited with which cytokines respectively?
IL-10 (C-type), TNFα (S-type)
Where are the first granulomas seen after MAP infection? How is this related to age-related risk?
Peyer’s patches. Number decline with age, therefore less infection in older animals.
Which cytokine and macrophage type are associated with MAP resilience?
IFNγ and type-1 macrophages
List 4 immunological variations associated with MAP susceptibility
Deficient MHC-II expression, decreased NO synthesis, increased TGF-β, increased IL-10
Which region of the gut provides most reliable johnes identification on histopathology?
ileo-caecal valve
What is the sensitivity of pooled faecal culutre for MAP? (What is the downside?)
92%. Very slow
Is MAP PCR more sensitive in faeces or milk? why?
Milk. Faecal PCR inhibitors.
What technique provides greatest sensitivity for MAP identification?
qPCR
What is the sensitivity of MAP ELISA in different clincial categories?
Clinical animals: 50-87%. Subclinical shedders: 24-64%. Non-shedders: 7-22%
What is the sensitivity of the IFNy assay for Johne’s? Which clinical class is it useful for? Name a downside to the test.
51%. Better than ELISA for identifying sub-clinical animals. Less specific in young animals
