Omya, the global producer of industrial minerals, has launched OmyaFeed® C MgO, a compacted feed material for ruminants which buffers rumen pH to an optimal level whilst providing essential calcium and magnesium nutrition. 

OmyaFeed C MgO is manufactured from finely ground (micronized), high purity calcium carbonate (CaCO3) and magnesium oxide (MgO). It is a highly palatable feed which protects dairy herds from sub-acute ruminal acidosis (SARA) by maintaining optimal rumen pH. 

David Bonsall, Technical Sales Manager for Animal Nutrition, Omya UK & Ireland, explains the issues caused by SARA. “To maximise milk yields, dairy herds are fed a high starch, low fibre diet. This puts them at risk of acidosis caused by the accumulation of volatile fatty acids in the rumen and its effect on gut biology. SARA is very common in the UK and can have a huge impact on both herd health and milk production. Fortunately, it can be alleviated by maintaining the correct pH in the rumen and by providing sufficient readily available calcium and magnesium. OmyaFeed C MgO does both these things.”

Independent trials undertaken by the Institute of Agrifood Research and Technology (IRTA) in Spain demonstrated the efficacy of OmyaFeed C MgO at much lower rates than other ruminal buffers. Only 130g/cow/day of OmyaFeed C MgO is required for effective rumen health, as opposed to more than double that amount for alternative buffers. This creates space in the ration, enabling farmers to enhance the feed formulation with additional materials or reduce the overall cost of the feed.

“OmyaFeed C MgO is a low dust, compacted product which mixes easily in the ration without segregation or settling,” continues Mr Bonsall. “This means it can be fed as part of a concentrated feed mix or added to silage. Because it is made from micronized minerals, it has a large surface area which improves solubility and enables rapid absorption. As calcium and magnesium are so important in dairy production, fast absorption and high bioavailability are key to herd health and high yields.”

OmyaFeed C MgO is produced using compaction technology and is certified under Feed Chain Alliance (FCA) standards.

To learn more about OmyaFeed C MgO and to review trials results, visit