Calf gastrointestinal health and function result from the intersection of three things:

• The nutrients the calf consumes
• The microbiota in the gastrointestinal tract
• The gastrointestinal tissue of the calf

Not all microbes are harmful, and keeping a healthy balance of commensal, or good bacteria, in the gut will help support this system. Finding ways to help promote a balance of all three parts above will ultimately result in a healthy calf.

Probiotics are “foods or supplements that contain live microorganisms that maintain or improve the ‘good’ bacteria (normal microflora) in the body,” according to the Mayo Clinic. A common probiotic you may have seen in the grocery store is kefir, a fermented milk beverage most easily described as drinkable yogurt. Kefir contains large amounts of probiotic bacteria, including lactic acid bacteria. Kefir has been shown to have antimicrobial properties and helps promote normal gut microflora and function. While you can buy it in the grocery store, kefir is relatively easy and inexpensive to prepare on a farm and feed to calves in milk or milk replacer.

At the Miner Institute, we recently completed a project funded by the Northern New York Agricultural Development Program that evaluated the effect of feeding kefir once daily to calves in the milk-fed phase (first three weeks of life). We made kefir on the farm with whole milk as needed, and one-quarter cup was fed to calves once daily.

An exciting result of this study was not what happened during the supplementation period but what happened closer to weaning. Calves supplemented with kefir had higher starter intake during weaning. Potentially, the kefir supplementation may have improved the balance of good bacteria in the gut, which helped calves eat more starter around weaning. We plan to follow up on this work to see if we can further improve the benefits of kefir feeding in calves and expand our understanding of how kefir supplementation promotes starter intake and calf development.