Additional Methionine for the Transition Phase

Claudia Parys

No one can deny that the vital role of rumen protected methionine, but the main challenge of using protected amino acids are very costly. I think that if the ration are balanced for amino acids and covered for limited amino acids, it will be decreased the feed costs.

Hazem,

You are right, protected amino acids are costly and there must be justifiable return on investment. I probably would not use it for cows yielding less than 8000lt. In any case, if you can determine the amount of yield of rumen microbial protein and compare that will milk output you tell whether or not the cow needs rumen protected amino acids. You also need to look at the whole diet and the RUP supply.

Hazem,

Cows do have a requirement for nitrogen in the rumen and for metabolizable amino acids in the intestine, the art of formulating a diet is precisely to cover these requirements in the most profitable possible way.

Mepron or any other protected amino acid is an amino acid, it is not a protein and it is not NPN, and it does not need to be, and it is intended to deliver its payload in the intestine, not to have an effect in the rumen (therefore, the word "protected").

A high producing cow rumen is just not capable of producing enough Methionine to cover its needs. Here it is the point where it comes RUP as Joe Magadi very rightly says, and the use of protected amino acids can be profitable at this stage.
Apart from the pure milk production (kgs, and fat and protein content) Methionine has other metabolic roles than can be very important in the transition stage.