Effect of malic acid in dairy cow diets

Summary

Fernando Diaz

Malic acid is a four-carbon dicarboxylic acid intermediate in the succinate–propionate pathway of ruminal bacteria. Research has shown that malic acid can stimulate the growth of Selenomonas ruminantium, improving the ruminal environment and increasing propionate production. This microorganism is the predominant specie in the rumen, representing from 21 to 51% of the total viable rumen bacteria.

In vitro, malic acid has increased concentrations of propionate and total volatile fatty acids, increased pH, decreased methane production and lactate concentration, and increased digestibility of dry matter (DM), organic matter, neutral detergent fibre (NDF).

Malic acid can be added to the diet either as the free acid, or as a salt (for example, calcium malate or sodium malate). Studies conducted in vitro showed that the effect of the free malic acid in the rumen is similar to the effect of disodium malate, although malic acid supplies the ruminal fluid with protons, which contributes to decrease ruminal pH.

Continue reading this article published in All About Feeds.