Nutrition and GI: Metabolic Disease in Ruminants Flashcards
What are the different diseases that can affect the dairy cow post natally?
‘post natal depression’
- Milk fever
- RFM, metritis, Endometritis
- Mastitis
- Displaced abomasum
- Ketosis
- Fertility
- Lameness
What risk factors of calving add to metabolic diseases?
- Reduced DMI
- Negative energy balance
- Immunosuppression
- What is milk fever?
- When does it affect dairy cows?
- Why?
- Hypocalcaemia ± hypophosphataemia
- At/after calving
- Drain on Ca2+ due to colostrum/milk demands
What controls Ca in the body?
Parathyroid hormone
* Mobilisation of Ca from bone
* Increased absorption from gut- Mg2+ required
Calcitonin- reduced Ca2+ absorption and availability
Vit D3= increases absorption from gut
What is generally the role of Ca2+ in the body?
- Muscle function
- Nerve impulses
- Immune response
What are the clinical signs of acute milk fever?
At/After calving
* Initial hyperexitation then recumbent
* Guts/glands stop
* No faeces
* No urination
* Dry noses
* Postural bloat
* Slow pulse/HR
What are the differential diagnosis for recumbent cow after calving?
- Milk fever- no faeces, slow/normal/fast HR
- Acute coliform mastitis- high pulse rate/HR, variable temp, endotoxaemic- mms conjested
- Botulism
- Acute disease- salmonella
- Injury at calving- nerve damage, femoral head
How is hypocalcaemia treated?
- I/V Ca Borogluconate 40% calcium- care with rapid infusion
- Place in sternal recumbency- bloat
What can be used for hypophosphataemia treatment?
Phosphorous containing products used for ketosis now used
* Vigophos solution injection- organis phosphorus, vitamin B12 supplementation
* Calciject 40CM for treating milk fever has 5% magnesium hypophosphite
How is milk fever prevented?
- Low Ca diet pre-calving
- High Mg pre-calving
- Boluses/drench/stomach tube at calving
- Maximise DMI pre-calving
- Aim for negative DCAD
- Zeolite- calcium binder
- What is DCAD?
- How can DCAD be monitored?
- Dietary anion/cation difference
DCAD = Na + K - C- S - Aim for negative DCAD before calving- reduce blood pH, monitor by urine pH below 6
Generally does not work easily in UK- grass high K
What can be done for a partial DCAD?
- Control diet for 14 days pre calving
- Housing therefore easiest
- Low potassium forages, no slurry on land used to harvest grass
- Magnesium chloride orally- flakes/water
When does hypocalcaemia affect sheep?
- Pre-lambing stress
- Movement back from ‘tack’
- Inadequate feed barrier space
- Often many recumbent ewes
Treatment
* 20ml Ca Borogluconate IV- diagnostic
* Farmer- 80ml CaBG S/C
- What is grass staggers?
- What causes it?
- Hypomagnesia
- No storage so when Output > input
Output- milk
Input- diet
* absorbed in rumen, retiuculm, omasum
* High K+ reduced absorption- lush grass, fertilisers
What are the clinical signs of grass staggers?
Peracute- often found dead
Early- twitchy and hypersensitive
Recumbent and convulsive
What effects epidemiology of staggers?
- Lush pastures
- High output of milk
- Stress- weather, movement, handling
Spring- dairy cows, twin bearing ewes
Autumn- suckler cows with large calf
How is staggers treated?
- Emergency
- Be quiet
- Control convulsions- xylazine, pentobarbitone
- Give Ca 40% IV
- Slowly give upto 200ml MgSO4 IV
How is staggers prevented?
- Move off affected pasture
- Give additional Mg
Dairy cows- high mag cake
Beef- minerals, bolus, wean calves, straw
What are ketone bodies function?
Energy sourve for muscle- not milk/brain
Feedback regulator for lipolysis
What causes ketosis?
- NEB
- Excessive mobilisation of fat for energy
- Insufficient prioprionate from rumen
- Insufficient oxalo-acetate
- Acetyl CoA from fat mobilisation cannot enter krebs cycle
- Acetyl CoA metabolised to ketones
What are the clinical signs of ketosis?
- Reduced milk yield
- Selective appetite- refuse concentrates
- Ketone bodies in blood
- Firm faeces- shiny
- Nervous ketosis
How is it treated?
- Propylene glycol
- Corticosteroids- dexameth
- Glucose 40% IV
- combination of above
- Vitamin B12
- Thiamine B1
- Kexxtone- monensin bolus
What is the function of a kextone bolus?
- Monensin- ‘antibiotic’
- Inhibits growth of gram +ve bacteria- produce most of the acetate, lactate and hydrohen
- Increase proprionate and glucose production
- 3-4 weeks prior to expected calving
- Target use- high or low BCS, twins, lame etc
When does sub-clinical ketosis occur?
How is it diagnosed?
How is it treated?
5-50 days in milk
Diagnosis
* BOHB in blood- 1.2-2.9mmol, > 3mmol- clinical
* NEFA in blood- >0.4mmol/l
Treatment- assess rations and dry cow managment
What are the BCS targets for:
1. Dry period
2. Early lactation
3. Drying off
4. Mid lactation
- 2.5-3
- 2-2.5
- 2.5-3
- 2.5-3
How can metabolic and nutritional status be monitored?
- Observation- BCS, DMI, rumen fill etc
- BHB
- NEFA
- Glucose
- Fat
- Protein
- Urea
- Calcium
How can milk quality be used for nutrition?
Both bulk tank and individual cow
* Milk protein- low MP, energy defecit
* Butterfat- low (lack of fibre), high (high fibre diet)
Urea- blood urea/milk urea will rise with excess ERDP or insufficient ME
How can rumen function be examined?
Faecal sieving
* Mucus
* Fibre length
* Grain processing
Rumen pH and protozoa
pH measuring boluses
How is fat metabolisation syndrome/ketosis prevented?
Feeding in dry period
* Low energy
* Maximise DMI in dry cows- comfort, palatable diet
Monitor CS
Avoid fat cows
