Metabolic disease in ruminants Flashcards
1
Q
What can cause post natal depression in the dairy cow?
A
- Milk fever.
- RFM / Metritis / Endometritis.
- Mastitis.
- Displaced abomasum.
- Ketosis.
- Fertility.
- Lameness.
2
Q
What is homeostatic control of Ca2+?
A
- Parathyroid Hormone PTH
– mobilisation of Ca2+ from bone “stores”
– increased absorption from gut (Requires Mg2+ to function) - Calcitonin – reduces Ca2+ absorption and availability
- Vitamin D3 – increased absorption from gut
- blood Ca2+ in two forms (50:50 – 60:40):
– Bound (chiefly to albumin)
– Ionised - Ca2+ - active
– pH dependant – reduced binding with reduced blood pH
3
Q
What is the role of Ca2+ in the body?
A
- Muscle function**
- Nerve impulses
- Immune response
4
Q
What is seen with acute milk fever?
A
- At/after calving =
- Initial hyper excitation – tremor etc
- RECUMBENT – muscles stop working
- Guts/glands etc stop working
- No faeces
- No urination
- Dry noses
- Postural bloat
- SLOW PULSE/HEART-RATE
- can be complicated by concurrent hypomag. and/or, hypophos
5
Q
What are Ddx for a recumbent cow?
A
- Milk fever - no faeces, normal/low temp
- Acute coliform mastitis - high pulse + HR, endotoxaemic
- Botulism
- Other acute diseases - salmonella
- Injury at calving - nerve damage (femoral + obturator), femoral head (ligament trauma)
6
Q
How can you treat downer cows?
A
- Milk fever - respond to Ca alone
- MF + hypophosphataemia = Ca + Phos
- Trauma / nerve damage = poor prognosis
7
Q
What is hypocalcaemia a risk factor for?
A
- Immune function depressed
- Coliform mastitis
- Metritis / endometritis
- Post partum depression
8
Q
How can you prevent hypocalcaemia?
A
- Feed low Ca diet pre-calving
- Feed high magnesium pre-calving
- Boluses / drench / stomach tube at calving
- Maximise DMI pre-calving
9
Q
When do you get hypocalcaemia in sheep?
A
- NOT after lambing
- Pre lambing = stress = movement back from tack, bad weather, inadequate feed barrier space
10
Q
What is grass staggers? How does it occur?
A
- Hypomagnaesemia - no body stores of Mg
- Output = milk, higher than input (diet)
- High K+ reduces Mg absorption = lush grass, fertilisers
11
Q
What are clinical signs of hypomagnesaemia?
A
- Peracute / acute = sudden death
- Early = twitchy + hypersensitive
- Recumbent + convulsive (emergency)
12
Q
What animals are predisposed to hypomagnesaemia?
A
- Stress = weather, movement, handling
- Spring = dairy cows + twin bearing ewes
- Autumn = suckler cows with large calf at foot
13
Q
How would you treat hypomagnesaemia?
A
- Control convulsions = xylazine, pentobarbitone
- Give Ca 40% IV
- Slowly give up to 200ml MgSO4 IV
- If not recumbent = bottle of MgSO4 SC
14
Q
How can you prevent hypomagnesaemia?
A
- Move off affected pasture
- Give additional Mg =
- Dairy cows - high Mag cake
- Beef cows - mineral supplements, Mag blouses, wean calves, give straw (slow gut transit time)
15
Q
What is fat mobilisation syndrome + ketosis?
A
- Energy deficit - NEB
- Excessive mobilisation of fat for energy
- ‘all cows develop NEB but not all develop ketosis/FMS’
