ANIMAL HUSBANDRY - Colostrum Management Flashcards
What is the structure of a bovine placenta?
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
Why are calves born in an immunocompromised state?
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
How do calves achieve passive immunity?
Calves need to ingest colostrum to develop passive immunity. Colostral antibodies will be absorbed via the neonatal enterocytes into the bloodstream
What is the main antibody found in colostrum?
IgG antibodies
When so calves begin to develop their own antibodies and active immunity?
Calves begin to develop their own antibodies and active immunity at approximately 1 week old
What are the consequences of failure of passive transfer in calves?
Calves with failure of passive transfer have higher morbidity and mortality rates and have poorer reproductive and productive performance as adults
What are some of the causes of failure of passive transfer in calves?
Cows not standing following calving, preventing the calf from suckling and colostrum collection
Weak calves
Poor quality colostrum
Reduced quantity of colostrum
Mis-mothering
What are the five ‘Qs’ of colostrum management?
Quantity
Quickly
Quality
Quiety
Quantify
What quantity of colostrum should calves be ingesting?
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
How quickly should calves be receiving colostrum?
Calves should be ingesting colostrum within the first 6 to 12 hours after calving
Why is it important for calves to ingest colostrum within 6 hours after calving?
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
Which how many hours should lambs ingest colostrum?
Lambs should ingest colostrum within 2 hours after lambing
How much IgG should colostrum contain for it to be considered quality colostrum?
At least 50g/litre of IgG within the colostrum
What is the gold standard test for measuring colostrum IgG levels?
Radial immunodiffusion
Why is radial immunodiffusion not commonly used?
Radial immunodiffusion is not commonly used as it is an expensive test to run
Which tests are used to measure colostrum IgG levels?
Colostrometer (not as commonly used)
Brix refractometry
How does brix refractometry measure colostrum IgG levels?
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
What total protein percentage on brix refractometry is equivalent to 50g/litre of IgG within the colostrum?
22%
How much bacteria within colostrum is ‘acceptable’?
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
How does bacterial contamination affect colostrum?
Bacterial contamination, especially coliform bacteria, reduces the intestinal absorption of the IgG within colostrum and increases the rate of neonatal enterocyte maturation
Why is it important to reduce stress when administering colostrum?
Stress increases serum cortisol levels, and increased cortisol levels decreases intestinal IgG absorption from the colostrum
How much IgG should be found within calf serum?
At least 10g/litre of serum IgG (however you should aim for at least 15g/litre of serum IgG)
When should calf serum IgG levels be measured?
Calf serum IgG levels should be measured between 24 hours and 7 days post calving
Why should you wait 24 hours post calving before measuring calf serum IgG levels?
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
Why can’t you measure calf serum IgG levels beyond 7 days post calving?
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
What is the gold standard test for measuring calf serum IgG levels?
Radial immunodiffusion
Which tests are used to measure calf serum IgG levels?
Total protein (done in lab)
Brix refractometry
How does brix refractometry measure serum IgG levels?
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
What total protein percentage on brix refractometry is equivalent to 10g/litre of IgG within calf serum?
8.5%
What can be done to compensate for poor quality colostrum?
You can compensate for poor quality colostrum by increasing the quantity of colostrum administered as this will increase the grams of IgG ingested
Why do colostrum feeds often need to be divided into several feeds?
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
What can be done to improve the effectiveness of colostrum?
- Make sure the calves are ingesting first milking colostrum only for the first few feeds
- Minimise time between calving and collecting colostrum from the cow
- Minimise time between calving and the calf’s first feed
- Minimise the time the collected colostrum sits in a bucket
- Appropriate selection of colostrum donors
- Colostrum pasteurisation
Address these issues in this order
Why is it important to minimise the time between calving and collecting the colostrum from the cow?
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
Why is it important to minimise the time the collected colostrum sits in a bucket?
The longer the collected colostrum sits in a bucket, the more bacterial contamination there will be which will reduce IgG absorption
What is colostrum pasteurisation?
Colostrum pasteurisation is the heat treatment of colostrum to reduce the bacterial contamination
How should colostrum pateurisation be carried out?
Colostrum pasteurisation should be carried out at 60°C for 60 minutes, higher temperatures will denature the antibodies
What should be done before resorting to pasteurisation to reduce the bacterial contamination of colostrum?
Other basic hygiene practices should be improved before resorting to pateurisation to decreases the bacterial contamination of colostrum
Which disease cannot be prevented by pasteurisation of colostrum?
Johne’s disease
Which cow factors can influence colostrum quality?
Delayed colostrum collection
Age
Breed
Length of dry period
High yield
Pre-calving nutrition
Vaccination
Disease
Season of calving
How long does the dry period have to be for the cow to produce adequate colostrum at calving?
For the cow to produce adequate colostrum at calving, they have to have had a dry period of at least 60 days
How does a high yield affect colostrum quality?
If a cow has high yield and produces over 8.5 litres of colostrum, this can have a dilutional effect on the colostrum
How does cow vaccination affect the colostrum quality?
Cows are vaccinated for rotavirus, salmonella and cryptosporidium at late gestation to enhance the antibody concentration within the colostrum against those specific pathogens
What should you do if the calf’s own mother’s colostrum is not available?
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
How should you store colostrum?
Colostrum needs to be stored in a lidded drum and stirred regularly, and can be preserved in the fridge, freezer or using potassium sorbate
How long can colostrum be stored in the fridge?
Colostrum should be stored in the fridge within 1 hour after collection and can be stored for 2 to 3 days at 4°C
How long can colostrum be stored in the freezer?
Colostrum can be stored in the freezer for 12 months at -20°C
