Investigating Under-performance in Dairy Herds

Question 1

What age should a heifer first calf and why?

Answer 1

24 months old as if this target isn’t achieved then it is difficult for the cow to catch up in productivity over her life span

Question 2

When should first service of a heifer be?

Answer 2

14-15 months old

Question 3

What should the weight and height of a heifer be at first service?

Answer 3

375kg

132cm

Question 4

Why might weight and height be a better measure for when first service should occur?

Answer 4

To reduce dystocia

To reduce overweight/underweight first time calvers

Question 5

What are the difficulties of height and weight measurements of heifers?

Answer 5

Measuring every 6 weeks is hard to do as requires time
Requires an investment in infrastructure
Consistency is key - always measure at same point (withers/pelvis)

Question 6

What is the calving score?

Answer 6

0 = no hand touches calf
1 = hand touches but no rope
2 = rope is used with a gentle pull
3 = rope is used and a hard pull
4 = Caesarian section

Question 7

What is live birth rate?

Answer 7

The percentage of calves born which are alive and survive for 24 hours

Question 8

What should be the target live birth rate?

Answer 8

97% in cows and 92% in heifers

Question 9

How should records be analysed?

Answer 9

Heifers vs cows
By bull/sire
By sex of calf
By operator

Question 10

What should be done if there seems to be problems around calvings?

Answer 10

Suggest training on routine calvings as discussions can reveal a problem that staff thought was too stupid to ask about

Question 11

What should be done with the calf at birth?

Answer 11

Navel should be dipped immediately in 7% iodine and totally immerse with this repeated again at 24 hours

Question 12

How much colostrum should a new born calf intake?

Answer 12

6 litres in first 12 hours of 6 pints in the first 6 hours

Question 13

When is absorption of colostrum best?

Answer 13

When suckled from the dam or when consumed in the presence of the dam

Question 14

What is the human intervention schedule for colostrum management?

Answer 14

2 litres in first hour, 2 litres in 6 hours, 2 litres in next 6 hours

Question 15

How should colostrum be collected?

Answer 15

From the first and second milkings into a stainless steel bucket which is checked for quality with a colostrometer

Question 16

How should colostrum be stored?

Answer 16

In the fridge at 4C for 24 hours or freeze immediately and thaw in warm water

Question 17

What objective measure can be used to assess colostrum intakes?

Answer 17

Blood sample 2-7 days using clotted red top tube for serum
Send to lab for zinc sulphate turbidity test or total protein
Use a refractometer = 55g/l

Question 18

How is calf milk replacer used?

Answer 18

For 12.5% feed 2 litres twice a day (125x2x2 = 0.5 kg/day)

For 15% feed 2.5 litres twice a day (150x2.5x2 = 0.75 kg/day)

Question 19

What is the objective of concentrate feeding?

Answer 19

Maximise calf concentrate intake by the time of weaning and when weaning occurs must already be eating sufficient concentrate

Question 20

What is a good example of concentrate feeding?

Answer 20

Keep concentrate fresh, changing 2x a day with guideline of 1kg per day intake at weaning

Question 21

What should be the approach to calf diarrhoea?

Answer 21

Look at environment, feeding and immune status of calves

Question 22

What is the calving index target?

Answer 22

365 days interfere at >380 days

Question 23

What is the earliest service date?

Answer 23

50 days and interfere if <42 days

Question 24

What is the calving to first service interval?

Answer 24

65 days and interfere if >75 days

Question 25

What is the calving to conception interval?

Answer 25

85 days and interfere if >95 days

Question 26

What is the conception at first service target?

Answer 26

60% interfere at <55%

Question 27

What is the conception in all services target?

Answer 27

55% interfere at <50%

Question 28

What is the target for 120 day in calf rate?

Answer 28

64%

Question 29

What is the target for 210 day not in calf rate?

Answer 29

<7%

Question 30

How is longevity measured?

Answer 30

Average number of lactations the cow lives before leaving the herd

Question 31

What does longevity indicate?

Answer 31

Significant welfare problem and is a key parameter to look at in any herd

Question 32

Why do planned culls need to occur?

Answer 32

To remove older or less productive cows from the herd to allow other cows in with cows killed due to illness preventing planned culls

Question 33

What should be done if there is a high cull rate?

Answer 33

Obtain a reason for culling data and get workers to rank out of 10 for the reason they were killed

Question 34

How should culls be analysed?

Answer 34

Reason, age, lactation, days in milk

Question 35

What should milk yield be compared to?

Answer 35

Expectation taking into account % fat and % protein