Is MetaSmart® better than Smartamine® M?

MetaSmart and Smartamine M are often compared to one another because they both supply methionine to the cow, but it is important to note that they are different products. MetaSmart is the isopropyl ester of HMB (methionine analog) and Smartamine M is based on a coated, true dl-methionine. The mode of action of the two products differs:

A) MetaSmart benefits rumen function and provides metabolizable methionine to the cow.
B) Smartamine M is solely a source of metabolizable methionine to the cow.

A trial with 70 cows was conducted at the University of Wisconsin with several objectives in mind. One of them was to compare (head-to-head) the impact each product would have on milk production and composition when fed to high-producing cows.¹

The cows were fed the same diet and either MetaSmart or Smartamine M was added to provide the estimated grams of required metabolizable methionine to maximize milk production and composition according to the NRC. This meant that 40 grams of dry MetaSmart or 15 grams of Smartamine M were added such that:

A) MetaSmart delivered 9 grams of HMB for ruminal use and 9 grams of HMB as a metabolizable methionine source to the cow.
B) Smartamine M delivered 9 grams of metabolizable methionine to the cow.

The cows fed MetaSmart produced 0.9 lbs. extra milk with .16% extra fat and .04% extra protein. To facilitate interpretation of those results, we recommend integrating these changes into a single number by calculating the Energy Corrected Milk (ECM). The cows fed MetaSmart produced 1.8 extra lbs of ECM; furthermore, they had lower Milk Urea Nitrogen than the cows fed Smartamine M.

a,b: Values with a different superscript are statistically different (P < 0.05)

The results from this research show that MetaSmart is just as good as Smartamine M as a metabolizable methionine source with the added benefit of improving rumen function.

¹Effect of feeding different sources of rumen-protected methionine on milk production and N-utilization in lactating dairy cows Chen et al., 2011 - J. Dairy Sci. 94:1978–1988