Cows need amino acids to maximise milk protein output as both litres and solids. Litres have always been king, yet increasingly milk companies are looking for higher milk protein levels and contracts are being implemented to encourage this. In order to ‘milk the contract’, we need to understand how milk protein levels can be increased, one way is to better understand the relationship between crude protein and the amino acid profile. Amino acid balancing has the potential to improve milk component and milk production, improve protein utilization and lessen dairy’s environmental impact.
Building Blocks of Protein
Protein is one of the key nutrients dairy cows need for optimal growth, milk components and milk production, reproduction and immunity.
Amino acids are the building blocks of peptides which are formed to create proteins and therefore one of the best ways to improve protein utilisation efficiency is by effective management of the amino acid profile.
The cow absorbs and uses individual amino acids rather than protein. She does not have a protein requirement but rather an individual requirement for each of the 20 amino acids at certain levels. Think of it like money – those annoying times when you have a tenner but need a pound coin for a car park machine. The pound coin is like the essential amino acid, you must have the correct one to proceed, and protein production by the cow is limited by the particular amino acid that is in shortest supply in the same way.
How do we know which Amino Acid is limiting?
Lots of research has helped direct good amino acid nutrition, this science has well established that the first limiting in milk production are the essential amino acids Methionine and Lysine. Lots of this work has been done at Cornell University so powering the rationing tools making this science practically and economically effective in our hands on farm.
Amino Acid Good Sources
Methionine Rapeseed meal, Rumen Protected Methionine, Fish meal when that was available.
Lysine Hi Pro Soya, Rumen Protected Lysine, again Fish meal was a good source
These essential amino acids cannot be synthesized by the cow, and consequently they must be delivered in the diet. Inadequate levels of these two essential building blocks for protein synthesis mean that milk components and milk production suffer.
So just put lots in then?
Often in an attempt to ensure that neither methionine or lysine is limiting in the diet crude protein is overfed to ‘flood’ the diet with amino acids blunderbuss style. Not only is this expensive, it can fail if the choice of feeds does not supply the amino acid balance that is required, so limiting production and wasting the non-limiting amino acids fed in excess. When urea is fed to increase the crude protein of the diet it must be known that it contains zero amino acids. All excess protein in diets ends up in the slurry pit as essentially expensive fertiliser, and this is the environmental concern of high protein feeding.
Accurate ration formulating matches supply with requirements, using directed amino acid nutrition where the balance of proteins is rationed for, and a favourable outcome is much more reliable. That outcome is maximising milk protein output through both litres and percentage solids. The tools to do this are available so please speak to us to find out more.