Metabollic Diseases Of Cattle

Question 1

What deficiencies does a cow with milk fever have?

Answer 1

Hypocalcaemia

+/- Hypophosphataemia

Question 2

What is the common signalment of a cow with milk fever?

Answer 2

Dairy cow after calving

Increasing parity - 3rd gestation onwards

Question 3

What element is important in parathyroid hormone function?

Answer 3

Magnesium

Question 4

What factor reduces calcium binding in the blood?

Answer 4

Acidic pH eg ketoacidosis

Question 5

What is the clinical presentation of acute hypocalcamia?

Answer 5

Shortly after calving
Initial excitability and tremors
Recumbency 
S bend neck - typical
No faeces or urine
Dry nose
Bloat 
Bradycardia

Question 6

What is the first thing you should do with a recumbent cow?

Answer 6

Put her in sternal to prevent bloat

Question 7

List some differentials for a recumbent cow following calving?

Answer 7

Milk fever
Acute coliform mastitis - high HR, pyrexia, congested mm, D+
Botulism
Other acute disease eg salmonellosis
Injury at calving - femoral / obturator n. ligament trauma

Question 8

What clinical signs are seen if hypophosphataemia is complicating milk fever?

Answer 8

Peri-parturient haemoglobinuria

Unable to rise fully after calcium (but responds after foston)

Question 9

How should you treat hypocalcaemia in the downer cow?

Answer 9

Put in sternal
1 bottle of calcium borogluconate 40% IV
Foston IV

Subcut is too slow to be absorbed if she is already down

Question 10

What diseases are cows predisposed to when there is sub clinical hypocalcaemia?

Answer 10

Coliform Mastitis

Endometritis / metritis

Question 11

How can a farmer prevent hypocalcaemia?

Answer 11

Low calcium / high magnesium diet pre calving
Maximise DMI pre calving
Calcium boluses at calving
Ensuring a dietary cation-anion difference
= negative difference - calcium mobilisation

Question 12

What is the presentation of hypocalcaemia in sheep?

Answer 12

Occurs pre lambing, due to a stressor causing a reduced dry matter intake
It presents as recumbent ewes

Question 13

How should you treat hypocalcaemia in sheep?

Answer 13

20ml of calcium borogluconate IV

Or 80ml subcut

Question 14

How does grass staggers (hypomagnesaemia) occur?

Answer 14

There are no body stores of Mg, relies totally on dietary intake

Anorexia - no magnesium intake

High potassium in the diet reduces Mg absorption -
lush pasture / fertilisers

Question 15

What are the clinical signs of grass staggers?

Answer 15

Peracute / acute - often found dead
Acute - initially muscle fassiculations and hyperaesthesia
- progressing to convulsions and recumbency

Question 16

What factors predispose to hypomagnesaemia?

Answer 16

Lush pasture
High milk output
Stress

Question 17

What groups of animals are affected with hypomagnesaemia in relation to the seasons?

Answer 17

Spring - seen in dairy cows and twin bearing ewes

Autumn - suckler cows with a large calf at foot

Question 18

How should you treat hypomagnesaemia?

Answer 18

1. Be quiet
2. Control convulsions - 5-7ml of xylazine IV
3. Calcium borogluconate 40% IV
4. Slowly give up to 200ml MgSO4 IV

If not you can give MgSO4 sc in multiple sites to aid absorption

Question 19

How can a farmer prevent hypomagnesaemia?

Answer 19

Move the cows off the affected pasture
Dairy Cows - high magnesium cake
Beef cows - magnesium supplements or boluses, wean calves, give straw to slow gut transit time

Question 20

What is the pathogenesis of fat mobilisation syndrome and ketoacidosis?

Answer 20

A negative energy balance leads to fat mobilisation and the use of acetate and butyrate to form ketone bodies
= energy source for the muscles but not for the brain
- leads to neurological signs as the brain is starved of nutrients

Question 21

What are the clinical signs of ketoacidosis?

Answer 21

Reduced milk yield
Refuses concentrates
Ketotic smell to the breath
Rothera’s reagent turns the milk purple (ketoacidosis)
Using ketosis ticks to measure ketone bodies
Firm, shiny faeces
Clinical signs of nervous ketosis - hyperexcitable, muscle fasiculations, maniacal licking

Question 22

What are some differentials for nervous ketosis?

Answer 22

Hypomagnaesaemia
Listeriosis
BSE

Question 23

How should you treat clinical ketoacidosis?

Answer 23

Propylene glycol
Corticosteroids
Glucose 40% IV
Vitamin B12

Question 24

What is the main clinical presentations of sub clinical ketoacidosis?

Answer 24

Reduce milk yield

Increased incidence of disease eg LDA, lameness, mastitis

Question 25

When do the 2 types of sub clinical Hypomagnaesaemia occur in cattle?

Answer 25

Type 1: 5-21 days post calving

Type 2: 22-50 days post calving

Question 26

How can you diagnose sub clinical ketoacidosis?

Answer 26

Beta hydroxybutyrate test
Test cows post calving - less than 10% above 1.4mmol/L

Non-essential fatty acids
Test dry cows in the last 14 days before calving
Less than 10% above 0.4 mmol/L

Milk recording - low protein in milk, very high butterfat %

Question 27

How can a farmer monitor his heard and prevent further sub clinical ketoacidosis?

Answer 27

Regular body condition scoring
Cows should be entering dry period BCS 2.5-3
Should not lose more than 0.5 of BCS in a lactation

DONT LET COWS GET FAT

Question 28

What should a farmer so to prevent sub clinical ketoacidosis occurring again?

Answer 28

Improve dry cow management 
Maximise DMI and feed a low energy density feed (8.5-9)
* maximise comfort 
* palatable diet 
* provide food at all times
Monitor condition score 
Don't let cows get fat