Betaine, also known as trimethylglycine, is a multifunctional compound that occurs naturally in plants and animals and is also available in various forms as a feed additive. The metabolic function of betaine as methylone is well known to most nutritionists.
Choline, methionine, and betaine are involved in the metabolism of methyl groups. Therefore, the addition of betaine can reduce the need for other methyl group donors.
You can get more information about natural and synthetic betaine at www.feedworks.com.au/betafin-comparing-natural-to-synthetic/.
Therefore, one of the known uses of betaine in animal feed is to replace (part of) choline chloride and add methionine to the diet. Depending on market prices, these substitutions generally save on feed costs while maintaining productivity yields.
When betaine is used to replace other methyl donors, betaine is used more as raw material, which means the dosage of betaine in feed formulas can vary and depend on the price of related compounds such as choline and methionine. But betaine is more than just a methyl contributing nutrient, and the inclusion of betaine in the diet should be seen as a means to increase productivity.
Betaine as an osmoprotectant
In addition to its function as methylone, betaine also acts as an osmoregulator. When betaine is not metabolized by the liver in the metabolism of methyl groups, it is available to cells for use as organic osmolytes.
As an osmolyte, betaine increases intracellular water retention but also protects cellular structures such as proteins, enzymes, and DNA. This osmoprotective property of betaine is very important for cells that are exposed to stress (osmotic).