Diet formulation for lactating dairy cows requires a thorough understanding of ruminant biology. Their unique digestive system makes them susceptible to disfunctions of the pre-stomachs when departing from their requirements. Successful nutritionist understand that they need to feed two interdependent systems, the host itself (the cow), and the microorganisms populating the rumen.
Supplying the reticulum and rumen with energy, nitrogen/protein, minerals and even vitamins, maximizes the growth of the microbial population and allows the fine-tuning of this symbiotic relationship. Different microbial groups within this population have specific needs and are specialized in their ability to degrade different substrates.
Folic acid and betaine activity on rumen microbiome and mammary gland
Recent studies for example have indicated that folic acid (FA) addition to the diet stimulated DNA synthesis in dairy cows and upregulated the gene expression related to protein synthesis in the mammary gland. Folic acid is reduced to tetrahydrofolate which is essential for the growth of Ruminococcus (R.) flavefaciens.
Dietary rumen-protected folic acid addition has increased cellulolytic bacteria population and the activity of its enzymes, α-amylase and protease. It has also had a positive effect on milk and milk protein yields. Betaine, the trimethyl derivative of glycine, arises from choline oxidation and is used in osmoregulation and transmethylation reactions.
Betaine donates a methyl group to regenerate methionine from homocysteine and is then converted to dimethylglycine. The methyl groups of the latter are split-off through oxidation and transferred to tetrahydrofolate to generate 5,10-methylene- tetrahydrofolate. Dietary betaine supplementation has been shown to increase intestinal microbes, digestive enzyme activities and nutrient digestibility in single-stomached animals and helped maintain the structure and activity of the mammary gland cells in dairy cows.