ANIMAL HUSBANDRY - Colostrum Management

Question 1

What is the structure of a bovine placenta?

Answer 1

Bovines have a syndesmochorial placenta which is characterised by the invasion of the foetal chorion into the maternal tissues, with partial loss of the materal epithelium to allow for efficient nutrient and waste exchange

Question 2

Why are calves born in an immunocompromised state?

Answer 2

Due to the syndesmochorial structure of the bovine placenta, there is no transplacental transmission of maternal antibodies to the foetus, and thus the calft is born in an immunocompromised state and very vunerable to pathogenic challenge

Question 3

How do calves achieve passive immunity?

Answer 3

Calves need to ingest colostrum to develop passive immunity. Colostral antibodies will be absorbed via the neonatal enterocytes into the bloodstream

Question 4

What is the main antibody found in colostrum?

Answer 4

IgG antibodies

Question 5

When do calves begin to develop their own antibodies and active immunity?

Answer 5

Calves begin to develop their own antibodies and active immunity at approximately 1 week old

Question 6

What are the consequences of failure of passive transfer in calves?

Answer 6

Calves with failure of passive transfer have higher morbidity and mortality rates and have poorer reproductive and productive performance as adults

Question 7

What are some of the causes of failure of passive transfer in calves?

Answer 7

Cows not standing following calving, preventing the calf from suckling and colostrum collection
Weak calves
Poor quality colostrum
Reduced quantity of colostrum
Mis-mothering

Question 8

What are the five ‘Qs’ of colostrum management?

Answer 8

Quantity
Quickly
Quality
Quiety
Quantify

Question 9

What quantity of colostrum should calves be ingesting?

Answer 9

Calves should be ingesting 10 - 12% (or 10 - 15%) of their body weight in colostrum

They keep switching between 10 - 12 and 10 - 15% in lectures

Question 10

How quickly should calves be receiving colostrum?

Answer 10

Calves should be ingesting colostrum within the first 6 to 12 hours after calving

Question 11

Why is it important for calves to ingest colostrum within 6 hours after calving?

Answer 11

It is important for calves to ingest colostrum within 6 to 12 hours after calving as the neonatal enterocytes are only permeable to antibodies within the first hours of life

Question 12

Within how many hours should lambs ingest colostrum?

Answer 12

Lambs should ingest colostrum within 2 hours after lambing

Question 13

How much IgG should colostrum contain for it to be considered quality colostrum?

Answer 13

At least 50g/litre of IgG within the colostrum

Question 14

What is the gold standard test for measuring colostrum IgG levels?

Answer 14

Radial immunodiffusion

Question 15

Why is radial immunodiffusion not commonly used?

Answer 15

Radial immunodiffusion is not commonly used as it is an expensive test to run

Question 16

Which tests are used to measure colostrum IgG levels?

Answer 16

Colostrometer (not as commonly used)
Brix refractometry

Question 17

How does brix refractometry measure colostrum IgG levels?

Answer 17

Brix refractometry provides an indirect estimate of colostrum IgG levels by measuring the total protein within the colostrum. This is very useful for herd evaluation but less so for individual cases

Question 18

What total protein percentage on brix refractometry is equivalent to 50g/litre of IgG within the colostrum?

Answer 18

22%

Question 19

How much bacteria within colostrum is ‘acceptable’?

Answer 19

Less than 100 000 CFU/ml total bacteria count (TBC)
Less than 10 000 CFU/ml total coliform count (TCC)

CFU stands for colony forming units

Question 20

How does bacterial contamination affect colostrum?

Answer 20

Bacterial contamination, especially coliform bacteria, reduces the intestinal absorption of the IgG within colostrum and increases the rate of neonatal enterocyte maturation

Question 21

Why is it important to reduce stress when administering colostrum?

Answer 21

Stress increases serum cortisol levels, and increased cortisol levels decreases intestinal IgG absorption from the colostrum

Question 22

How much IgG should be found within calf serum?

Answer 22

At least 10g/litre of serum IgG (however you should aim for at least 15g/litre of serum IgG)

Question 23

When should calf serum IgG levels be measured?

Answer 23

Calf serum IgG levels should be measured between 24 hours and 7 days post calving

Question 24

Why should you wait 24 hours post calving before measuring calf serum IgG levels?

Answer 24

You should wait 24 hours post-calving before measuring calf serum IgG levels as this will allow enough time for intestinal absorption of the antibodies within the colostrum into the bloodstream

Question 25

Why can't you measure calf serum IgG levels beyond 7 days post calving?

Answer 25

You cannot measure calf serum IgG levels beyond 7 days post-calving as at this point, calves will have started to produce their own antibodies and develop active immunity

Question 26

What is the gold standard test for measuring calf serum IgG levels?

Answer 26

Radial immunodiffusion

Question 27

Which tests are used to measure calf serum IgG levels?

Answer 27

Total protein (done in lab) Brix refractometry

Question 28

How does brix refractometry measure serum IgG levels?

Answer 28

Brix refractometry provides an indirect estimate of serum IgG levels by measuring the total protein within the plasma. This is very useful for herd evaluation but less so for individual cases

Question 29

What total protein percentage on brix refractometry is equivalent to 10g/litre of IgG within calf serum?

Answer 29

8.5%

Question 30

What can be done to compensate for poor quality colostrum?

Answer 30

You can compensate for poor quality colostrum by increasing the quantity of colostrum administered as this will increase the grams of IgG ingested

Question 31

Why do colostrum feeds often need to be divided into several feeds?

Answer 31

Colostrum feeds often need to be divided into several feeds as the neonatal abomasal capacity is approximately 2 - 3 litres and often calves will require a larger volume of colostrum than the abomasal capacity

Question 32

What can be done to improve the effectiveness of colostrum?

Answer 32

1. Make sure the calves are getting first milking colostrum 2. Minimise time between calving and collecting colostrum from the cow 3. Minimise time between calving and the calf's first feed 4. Minimise the time the collected colostrum sits in a bucket 5. Appropriate selection of colostrum donors 6. Colostrum pasteurisation | Address these issues in this order

Question 33

Why is it important to minimise the time between calving and collecting the colostrum from the cow?

Answer 33

The longer the colostrum sits in the udder, the increased risk of the IgG concentrations declining as the cows will begin to produce milk which will dilute the colostrum within the udders

Question 34

Why is it important to minimise the time the collected colostrum sits in a bucket?

Answer 34

The longer the collected colostrum sits in a bucket, the more bacterial contamination there will be which will reduce IgG absorption

Question 35

What is colostrum pasteurisation?

Answer 35

Colostrum pasteurisation is the heat treatment of colostrum to reduce the bacterial contamination

Question 36

How should colostrum pasteurisation be carried out?

Answer 36

Colostrum pasteurisation should be carried out at 60°C for 60 minutes, higher temperatures will denature the antibodies

Question 37

What should be done before resorting to pasteurisation to reduce the bacterial contamination of colostrum?

Answer 37

Other basic hygiene practices should be improved before resorting to pateurisation to decreases the bacterial contamination of colostrum

Question 38

Which disease cannot be prevented by pasteurisation of colostrum?

Answer 38

Johne's disease

Question 39

Which cow factors can influence colostrum quality?

Answer 39

Delayed colostrum collection Age Breed Length of dry period High yield Pre-calving nutrition Vaccination Disease Season of calving

Question 40

How long does the dry period have to be for the cow to produce adequate colostrum at calving?

Answer 40

For the cow to produce adequate colostrum at calving, they have to have had a dry period of at least 60 days

Question 41

How does a high yield affect colostrum quality?

Answer 41

If a cow has high yield and produces over 8.5 litres of colostrum, this can have a dilutional effect on the colostrum

Question 42

How does cow vaccination affect the colostrum quality?

Answer 42

Cows are vaccinated for rotavirus, salmonella and cryptosporidium at late gestation to enhance the antibody concentration within the colostrum against those specific pathogens

Question 43

What should you do if the calf's own mother's colostrum is not available?

Answer 43

Use fresh colostrum from another cow from the same farm Use frozen colostrum from another cow from the same farm Use artifical colostrum Use colostrum from another farm

Question 44

How should you store colostrum?

Answer 44

Colostrum needs to be stored in a lidded drum and stirred regularly, and can be preserved in the fridge, freezer or using potassium sorbate

Question 45

How long can colostrum be stored in the fridge?

Answer 45

Colostrum should be stored in the fridge within 1 hour after collection and can be stored for 2 to 3 days at 4°C

Question 46

How long can colostrum be stored in the freezer?

Answer 46

Colostrum can be stored in the freezer for 12 months at -20°C