10/08/2025                                                                            
                                    
                                                                            
                                            Why Fine Ground Limestone Matters for Milk Fever Prevention â and How MineralBoost Delivers It Best
Milk fever (hypocalcaemia) is one of the most costly metabolic issues for New Zealand dairy farmers, with each case estimated to cost around $500 when factoring in lost production, treatment costs, and increased risk of follow-on diseases. But hereâs the thing â preventing clinical milk fever alone isnât enough. Subclinical hypocalcaemia (SCH) affects far more cows, especially older and high-producing animals, and quietly chips away at production, reproduction, and cow health.
Calcium â the Cornerstone of Prevention
Calcium is essential for muscle function, nerve signaling, and milk production. At calving, demand for calcium skyrockets. Without adequate supply and availability, cows risk going down, suffering difficult calvings, or facing slower recoveries. Even cows that never âgo downâ can still be underperforming due to low blood calcium levels.
Thatâs why the quality and availability of your calcium source matters just as much as the quantity.
The OmyaFeed Fine Lime
In 2018, Omya Australia tested its OmyaFeedÂŽ superfine limestone (20 microns) against common coarse limes in an in-rumen digestibility trial at the NSW Department of Primary Industries, Wagga Wagga. The results were striking:
OmyaFeedÂŽ digested 240% more efficiently than the coarse alternatives.
At a standard feeding rate of 150g/head/day, OmyaFeedÂŽ could release 54g of calcium into the rumen â compared to just 22g from coarse lime.
The key is particle size and availability. Superfine limestone offers vastly more surface area for rumen microbes to work on, meaning faster and more complete calcium release when the cow needs it most. And unlike raw fine powders, OmyaFeedÂŽ is bound into a granule with molasses, making it dust-free, palatable, and easy to handle.
Why This Matters for Milk Fever
When you feed a coarse lime, much of the calcium passes through unused â a hidden waste that can cost you in production losses and cow health. With Omyaâs fine lime in MineralBoost, you get maximum bioavailability, ensuring that your cows are actually absorbing the calcium youâve invested in.
Better calcium absorption means:
* Reduced risk of clinical and subclinical milk fever
* Improved muscle tone for calving and faster recovery
* Lower incidence of retained membranes and post-calving infections
* Higher feed efficiency and production during early lactation
MineralBoost â All She Needs
MineralBoost uses Omyaâs high-grade fine lime within its patented rumen-dispersible granules. This eliminates the dust, handling, and segregation problems of powdered minerals while ensuring every mouthful of feed delivers exactly the right mineral balance.
With Calcium, Magnesium, and Sodium as the foundation â plus optional trace minerals and additives â MineralBoost ensures your herd gets the best start to lactation, setting them up for strong peak production and fewer metabolic setbacks.
Bottom line: 
Fine ground limestone isnât just a detail â itâs the difference between preventing milk fever effectively and just ticking the box. With MineralBoost, youâre not only giving your cows more calcium, youâre giving them calcium they can actually use.
Contact your local MineralBoost representative today to discuss how to get Omya fine lime working for your herd.
0800 466 736                                        
                                    
                                                                        
                                        MineralBoost is a Rumen Dispersable Granule designed to balance dairy cattle feed rations. Available from all leading Rural Merchants and Stockfeed companies.