Production diseases: HypocalcaemiaHypomagnesaemiaHypophosphatemia

Question 1

Why is hypocalcaemia a gateway for other conditions during transition period

Answer 1

HypoC causes reduced SM function

Question 2

Normal calcium level for cow

Answer 2

2-2.5mmol/l

Question 3

When is the typical onset of hypoc

Answer 3

12-24h post partum

Question 4

T/F 50% of older cows have subclinical hypoc

Answer 4

Yes. 1.38-2.0mmol

Question 5

How to monitor calcium level

Answer 5

LAQUA twin device measures ionised calcium level

Question 6

What is typical ionised calcium level

Answer 6

> 1.0mmol/l

Question 7

At what level of calcium level is the clinical syndrome ‘milk fever’ and the cows go down

Answer 7

<1.4mmol/l

Question 8

What breed is more susceptible to milk fever

Answer 8

Jersey/Guernsey

Question 9

C/S of stage 1 milk fever

Answer 9

Excitability/Nervous
Weak
Shift weight and shuffle hind feet

Question 10

C/S of stage 2 milk fever

Answer 10

Sternal recumbency
Moderate-Severe depression
Partial paralysis

Question 11

C/S of stage 3 milk fever

Answer 11

Lateral recumbency
Completely paralyzed
Bloated
Severe depression to coma

Question 12

Milk fever treatment for Stage 1

Answer 12

Oral calcium and SC calcium

Question 13

Milk fever treatment for Stage 2 and 3

Answer 13

IV calcium through jugular vein
400ml of 40% calcium borogluconate (12g calcium)
Follow up with oral and SC calcium

Question 14

What is important to note during milk fever treatment

Answer 14

Slow administration over 5-10 min
Sudden increase in HR/Arrhythmia

Question 15

Outline 5 ways to prevent hypoC with regards to nutrition

Answer 15

1. Low calcium diet pre partum 3 weeks
2. Clay based binder of calcium
3. Vitamin D supplement
4. Assurance dietary magnesium supply
5. Dietary Cation Anion Difference DCAD diet to increase PTH activity

Question 16

Other ways to prevent HypoC besides nutrition

Answer 16

Calcium supplementation at calving
Avoid stress and overcrowding
No group mixing
Feed management

Question 17

T/F Magnesium levels are moderated by hormones

Answer 17

False. Purely based on dietary intake

Question 18

Hypomagnesemia is more common in beef or dairy?

Answer 18

More common in beef

Question 19

T/F Hypomagnesemia is a risk factor for milk fever

Answer 19

Yes

Question 20

Suggest reasons for hypomagnesemia

Answer 20

Lush grass
Low fibre
Older cows
Weather (rain leaching)
Inadequate supply

Question 21

Normal level of magnesium in plasma and CSF

Answer 21

Plasma: 0.8-1.0mmol
CSF: ¬1.0mmol/l

Question 22

Treatment option for Hypomag

Answer 22

Mg IV/SC/Oral
Mg SC is first choice. Sometimes calcium supplement contains Mg
IV Mg is dangerous if seizing. Sedate animal first. Slow admin of Mg

Question 23

Hypomag control and prevention

Answer 23

Pottasium and sodium content in diet
Molasses based stick buckets
Concentrates with Mg and Na
Water medicated with Mg salt
Intraruminal boluses containing Mg

Question 24

Normal phosphate level in cow

Answer 24

1.4-2.6 mmol/l
Higher in growing animal

Question 25

Considerations when blood sampling for phosphate

Answer 25

Difference in levels between jugular and tail Haemolysed sample increases phosphate level Sample collection and processing

Question 26

What is hallmark clinical sign of acute hypophosphataemia

Answer 26

Muscle weakness/Recumbency Periparturient haemoglobinuria

Question 27

HypoP treatment

Answer 27

Oral supplementation 150-250g if anorexic Slow IV injection sodium phosphate salts