Genetics suppliers have done a great job selecting for a high-lean gain rates in pigs today. As a result pigs produce much more heat, which poses greater risk in the event of ventilation failure. What’s more, it’s been estimated that every 10 years or so pigs’ heat production increases by about 15 percent.

“Muscle deposition generates more heat than fat deposition,” says Mike Brumm, Brumm Swine Consultancy, Mankato, Minn. A 220-pound pig generates about 900 BTUs per hour, and nearly 1,000 BTUs from a market-weight pig.

In the event of a ventilation failure, the heat produced can rapidly become deadly for pigs.  “Air temperature in the barn can rise faster than one degree per minute,” Brumm says. “Death loss will result from organ failure due to heat.”

With heavy pigs, it’s critical that heat removal begin within 30 minutes of a ventilation failure to prevent pig deaths, Brumm notes, which is why curtain drops are so critical.

With 50-pound pigs in a nursery, death can result in as little as one hour if ventilation failure occurs. Protection against heat build-up with override thermostats, curtain drops and generators is critical. “Be sure to place override devices in a location that ensures an accurate reading and not in some dark corner,” Brumm says.

Written records are important when making insurance claims on losses. “If you use curtain drops as emergency heat relief, test the drops at least times several a year,” Brumm says. “Also, be sure to record the tests you perform on emergency equipment and sign and date them for records.”  In the event of a loss, it will provide proof that the system was maintained.