October 10, 2016
We have been warned for a week now that the approaching weekend is going to be scorching hot with dangerously high heat indexes close to 110. Heat stroke in the cow occurs when body temperature exceeds 106. Once body temperature climbs above 108, permanent brain damage will occur from which the cow will be unable to recover. When you find an animal suffering from heat stroke, immediate treatment is necessary. We need to rapidly move heat away from the cow through continuous flow cool water and fan. Run a hose continuously over the cow for 30 minutes while blowing a high velocity fan over her. The flow of water will move heat away from her body and a fan will provide evaporative cooling. A deep bed sand pack is cooler than a straw/sawdust bed pack. Always provide fresh feed and water.
To minimize the affects of heat stress, Provide sprinklers and fans along the feed line and milking parlor holding area (the area of greatest heat stress). Provide 4″ of water trough space per cow with water access provided as cows exit the parlor. If you do not have sprinklers, soak the cows in the holding area or as they exit the parlor. Provide fresh TMR at night or first thing in the morning when the cows are more comfortable and intakes are higher. Sand bedded freestalls or bedpacks are also beneficial. The same concepts are critical for dry cow management as well. The dry cow and developing calf are affected by heat stress. Provide fresh free choice water to calves, increase fluid/energy intake (heat stress increases energy demands by 30%), and increase ventilation in calf hutches.
And…Do not forget to take care of yourself! Exertion heat stroke or exhaustion can occur in hours with body temperature exceeding 104F. Dizziness and delirium, excessive sweating changing to no sweating, rapid heart rate and breathing are typical symptoms. Rest. Drink fluids and electrolyte solutions. Cool yourself with a fan and water. Rub cool water and/or rubbing alcohol on your arms and legs and neck. Jump in a pool, water trough, or other water sources.