Young dairy calves especially susceptable to heat

The heat wave is causing some real problems for young dairy calves in hutches. The Wisconsin Veterinary Diagnostic Lab (WVDL) says a number of dairy herds have reported calf losses and all involve calves 2 to 7 days old in hutches. Officials at the lab say the calves are either weakened by heat stress and die from a bacterial infection or they become dehydrated and die from heat stroke.  Donald Sockett DVM says calves under ten days of age tend to not drink enough water and suggests some preventative measures.

“Dairy operators who are expecting calves or who have very new calves are advised to follow some of the same procedures used in high heat areas of the country, like Arizona, where it is common practice to hose down 1-7 day-old calves with cool water in the late afternoon.”

Likewise, he advises dairy operators to configure calf hutches to take advantage of prevailing winds by orienting them in an east-west direction, with the front facing east and preferably in the shade. Hutches should not be placed in gullies or next to buildings that restrict access to prevailing winds and ventilation vents in the hutch should be open at all times. Ideally, the rear of the hutch should be elevated 16 inches, but a minimum of 12 inches is acceptable. Finally, Sockett advises that the hutches be bedded with sand or wood shavings and be separated by at least four feet.

“In hutches that are not set up for summer, veterinarians are finding that the ambient temperature inside is often 5 to 10 degrees higher than the outside temperature, which elevates the calf’s core body temperature to between 103 and 105 degrees,” Sockett says. Core body temperature consistent with heat stroke is 108 to 110 degrees.

Finally, water or electrolytes should be available to the calves at all times and calf managers should monitor the temperature inside the occupied hutches. If the hutch ambient temperature is the same or warmer than the outside temperature, there may be something wrong with the heat abatement procedures and steps must be immediately taken to correct the problem.