Care for Calves in Hot Weather


The extended forecast will put animals well into heat stress. Beyond a reduction in feed intake, calves can become dehydrated, over heated, and their gut lining will be stressed and “leaky”- or open to pathogens. Keep the points below in mind:


Entice Water Consumption

  • Offer WARM water immediately after feeding milk. Cold water requires the calf to expend more energy to bring the water to body temperature.
  • Offer warm water in bottles to calves that do not drink out of pails. Just because they may be younger does not mean they don’t require extra hydration.
  • Add an electrolyte feeding in addition to water – a great option is Land O Lakes electrolyte base. Do this between feedings if possible, or leave in buckets overnight or in a pail in a group pen. This must be cleaned daily.
  • Calves will get up at night to drink water- be sure it is there!


Fly Stress

  • Use a pour on to deter flies away from calves… flies are exploding right now and can rapidly dehydrate calves.
  • Keep the air moving in barns! Fans by the milk area/feeding station will be important to lower flies in high traffic areas. Fans near grain will deter flies from settling in for a calf-grain snack!

Weaned calves

  • Weaning is already considered a significant stress event and stress means high cortisol, which can be a signal to pathogenic bacteria to begin colonization. Add this with a leaky gut and calves are significantly compromised.
  • Fans, see above.
  • Use a stress tub especially if you had preweaning challenges with calves. Leave in the pen 10-14 days.
  • Consider a few days of electrolytes to keep calves hydrated.
  • Delay weaning for any “challenged” calves.


Future Notes

  • Pneumonia for calves can develop following heat stress up to a few weeks. Be on the watch.
  • Because heat stress can depress feed intake, length of time on grain prior to moving to fermented forages may be prolonged by a week or 2 to ensure adequate rumen development.

For more information on electrolytes, stress tubs, and heat stress abatement ideas, please feel free to contact me or the Ag Partners nutritionist you work with!



Rebekah Mathews, M.S.

Calf & Heifer Nutrition Specialist

Ag Partners

(612) 237-0714