Small Ruminants: Disease of Adult Sheep- GI and Respiratory Flashcards
What dental disease can be in adult sheep?
Incisors- broken mouth
Molar teeth- uneven wear, sharp edges (painful and difficult to eat)
How can sheep be aged using incisors?
Permanent incisors erupt in the order from central to peripheral from 1-4 years
What does this image show?
A ewe with broken mouth
How should a ewes mouth be examined for dental disease?
Palpation externally- jaw, lymph nodes, face, halitosis, external palpation for pain
Gag and torch internally
Radiography
What is quidding a sign of?
Molar teeth disease
What causes dental disease in sheep?
What is the solution?
Ageing, Peridontal disease
(bacteria, maloccluson, diet)
Cull
Sedation-rasp (pet sheep)
What are the agents for the followind diseases?
* Wooden tongue
* Lumpy jaw
* Calf diptheria (necrotic stomatitis)
Wooden tongue- Actinobacillosis lignerisei
Lumpy jaw- Actinomycosis bovis
Calf diptheria- Fusoforum necrophorum
What can cause pharyngeal trauma?
What is the normal history and clinical signs?
Prognosis?
Dosing guns- common
History- few days, weeks after drenching
Clinical signs- dull depressed, inappetant, halitosis, pain
Prognosis- poor
- What is the agent of Johne’s disease?
- How is it spread
- When is the key risk period?
- Where does the disease replicate?
- When does clinical disease affect sheep?
- Mycobacterium avium paratuberculosis
- Spread faecal oral- faeces, colostrum, in utero
- First 3-4 months of life
- Replicates in GI lymph nodes and gut- long incubation
- Typically 3-4 years old
What is the pathology of Johne’s disease?
- Cellular infiltration, thickening of intestines
- Malabsorption and protein losing enteropathy
- Hypoalbuminaemia
What are the clinical signs of Johne’s Disease?
- Weight loss
- Anaemia
- Bottle jaw
- Sheep over 1 yo
- High parasite burdens
- Non-specific- suspicious high culling rate of thin sheep
How is Johne’s disease diagnosed?
- Complex- tests have low sensitivity
- Post mortem- gold standard (enlarged distal mesenteric lymph nodes)
- Serology ELISA antibody- low sensitivity, good specificity
- PCR faeces- intermittent shedding
- Faecal culture- specific, time consuming
What does high/low sensitivity mean?
What does high/low specifcity mean?
High sensitivity- few fale negatives
Low sensitivity- high false negatives
High specificity- few false positives
Low specicifity- high false positives
How would Johne’s be diagnosed with one clinical case or flock testing?
Clinical case with clinical signs- Faecal PCR, ELISA, PM
Flock tests- select older thinner ewes >3 yo, PCR faecal antigen or with PCR
Can Johne’s be successfully be vaccinated against?
Vaccine available Gudair (Virbac)
Does not prevent infection but reduces clinical cases and excretion of bacteria
All lambs 4 and 16w
Repeated anually