Easy as 1, 2, 3!
If you've ever raised a calf, you've probably heard the 1-2-3 rule of colostrum management: feed from the 1st milk, within the first 2 hours of life, and at least 3 litres.
Why is this important?
Colostrum provides not only nutrition, but also essential immunity to the newborn calf. This immunity helps protect them against common infections such as scour and pneumonia, and can make the difference between a strong healthy calf that never sees a vet, and an ill-thrifty calf that requires numerous costly vet visits and antibiotics.
Following the 1-2-3 rule maximises the benefit of this immunity. Using the cow's first milk and giving at least 3 litres ensures that the calf's first feed is packed with strong immunity and nutrition. It is essential that they receive this as soon as possible, always within the first 2 hours of life, because their ability to absorb this immunity starts to decline almost immediately after birth.
But wait, there's more!
Following the 1-2-3 rule has lifelong benefits. Not only do calves with good colostrum management thrive better, they are proven to be healthier and more productive adult cows.
Not all colostrum is created equal.
What exactly makes colostrum 'high quality?'
* Immunity content - IgG is an immune protein which can be measured as an indication of the overall level of immunity contained within the colostrum. The higher the IgG, the stronger the immunity the calf receives. Good colostrum should contain at least 50g/L of IgG.
* Nutritional content - colostrum should contain a complete and balanced diet for the newborn calf, including vitamins and minerals.
* Free from contaminants and pathogens - Colostrum is of little use if it exposes the calf to potentially serious infection. Colostrum should contain as little bacterial contamination as possible. Colostrum from cows with diseases which are transmittable through milk (such as mastitis, Johne's disease, Mycoplasma, or Salmonella) should not be fed.
Colostrum quality varies significantly between cows for a variety of reasons
* Breed - Though the quality of the colostrum itself does not vary predictibly between breeds, the large volume of milk produced by dairy breeds means that if there is any delay between birth and the first feed of colostrum, the concentration and therefore the level of immunity the calf receives is rapidly reduced. For this reason dairy cows have a reputation (though perhaps an unfair one) of having poorer colostrum than beef cowsd, and dairy calves a weaker immune system.
* Age - Like a good wine, colostrum gets better with age. Older cows generally produced better quality colostrum than heifers.
* Overall health - Cows with better nutritional status and which are free from illness will produce better quality colostrum as they are able to devote more resources to it. Cows with nutritional deficiencies, particularly selenium or vitamin E deficiency which are often seen in the Wicklow area, will produce smaller quantities of lower quality colostrum. Colostrum from cows which are in any way ill should never be fed to calves as this can transmit disease.
* Vaccination - The value of the immunity provided by colostrum is maximised if it is tailored to the diseases the calf is likely to be exposed to - vaccinations are a great way to achieve this. Vaccines given around 3-6 weeks pre-calving, usually for causes of scour such as Rotavirus, Coronavirus, E. coli, and Salmonella, stimulates the cow to produce specific immunity against these diseases which is transfered in the form of IgG into colostrum and on to the calf.
* Dry period - The dry period should be at least 3-4 weeks, any less than this doesn't allow the mammary glands sufficient time to rest and recover before the demanding process of making colostrum, and does not allow enough time for response to vaccines and transfer of IgG. A dry period of at least 40 days will maximize the volume of colostrum produced.
What else do I need to know?
How to feed - Don't rely on the calf! Even if you see them stand to suck, you can never be sure what volume they have taken. Calves should always be stomach tubed or bottle fed so there is no doubt as to exactly how much they have recieved.
Colostrum storage and thawing - Colostrum from healthy cows (rather than heifers) should be frozen and stored in 1L containers which can be gently and evenly thawed in warm water (temp no greater than 50C). Colostrum should never be microwaved or placed in boiling water. It can be safely stored for up to 12 months at -18 to -25C, or up to 24 hours in a refridgerator. Colostrum from neighbouring farms should be avoided due to risk of introducing disease.
Artificial colostrum - There is absolutely no comparison to the real thing. Colostrum from the cow has richer nutrition, stronger immunity, and is absorbed much better. Replacement colostrum can be used in an emergency, but products are variable so make sure to ask your vet for advice.
How do I know I'm getting it right?
* RID - The gold standard of measuring colostrum quality, but expensive and samples must be sent to a lab, so it's not a very practical test.
* Brix Refractometer (Optical or Digital) - A small sample of colostrum is applied and a digital reading is given. A brix reading of >22% correlates to >50g/L of IgG and therefore an adequate level of immunity.
* Colostrometer - A glass float which is placed in room temperature colostrum. The higher the IgG content the more dense the colostrum, and the higher the colostrometer floats above the surface. They are generally marked to indicate good, adequate, and poor colostrum quality.
Measuring calf immunity (Calves 1-3 days old)
* Total Protein Refractometer - A small blood sample can be taken and the serum separated out. A drop of serum is applied to the refractometer and reading taken of the total protein, which can be used as an indicator of the level of IgG in the calf's bloodstream. This value should be at least 5.5g/dL to indicate adequate transfer of immunity, <5.0g/dL indicates complete failure of immune transfer. This is not a reliable test in sick or dehydrated calves.
* Brix refractometer - Uses calf serumm very similarly to a total protein refractomer, however the measurement is taken on the Brix scale. The exact cutoff hasn't been firmly established, but a reading of at least at least 8-10% suggests adequate transfer of immunity.
* ZST - A lab test run on a small blood sample. Results of 16-20 are acceptable, but should be at least 24 to confirm successful transefer of immunity.