Heat-stressed dairy cows should be fed adequate amounts of trace minerals and vitamins, particularly antioxidant nutrients. At this time, research trials where additional trace minerals or vitamins have been added to diets of cows under heat stress have not consistently shown a benefit. More research is needed before additional amounts and sources of trace minerals are recommended to be added to diets of heat-stressed dairy cows.
Rations for dairy cows should be formulated for dairy cows before heat stress occurs and should contain:
- 1.4 percent to 1.6 percent potassium
- 0.35 percent to 0.45 percent sodium
- 0.22 percent to 0.35 percent magnesium (readily available source)
- +25 to 30 or greater DCAD balance