Low potassium grasses reduce health problems in dairy cows
Soil testing, choosing the right grasses and proper storage can keep dairy cattle healthier and encourage higher production
Early lactation cows often experience low blood calcium due to the demands of the onset of lactation. The resulting hypocalcemia can result in milk fever, retained placenta and mastitis as well as other metabolic disorders. High concentrations of potassium (K) in forages fed to dry cows can have a large influence on the incidence of hypocalcemia in early lactation cows.
Implementation of a separate management group for dry cows that are from three to four weeks pre-calving to calving, enables the feeding of a special transition diet. A primary goal is to reduce the concentration of K consumed by the cows before calving. The purpose of this article is to provide information on managing K levels in the diet of transition cows.
Low K Rations
There are several methods for managing dietary K concentrations in transition cow diets. Inclusion of significant amounts of low K corn silage and/or straw can lower ration K. A second approach utilizes the addition of blood acidifying anionic salts to the ration. Low K grains or other feedstuffs also may be employed to dilute the K concentrations in transition rations. A fourth method is to produce and feed low-K hay forage specifically for the group of transition cows on the farm.
Keys to producing low K dry-cow grass hay
- Choose timothy or reed canary grass and avoid orchardgrass
- Soil test to select and monitor low K fields for growing transition cow hay
- Apply 100 lb actual N at spring green up and after first cutting
- Avoid K fertilizers and manures until demonstrated as needed
- Take 2 cuttings per year harvested as dry hay if possible
- Store low K hay separately for feeding to transition cows
- Utilize wet chemistry feed analysis to balance rations and monitor forage K concentrations