Low propane supplies and high propane prices have caused concerns among U.S. poultry farmers who rely on the fuel to keep their poultry houses warm amid the cold winter months.

Poultry producer Jeremy Brown, Ramer, Ala., told the Montgomery Advertiser he uses heaters fueled by propane to keep temperatures around 90 degrees in his six poultry houses, which each house about 28,500 chicks. Should that source of heat not be available, Brown said, the chicks would not survive.

The tight supplies have pushed prices to about $4.50 per gallon from the $.80 range they were at during the summer of 2013. "It's the highest I've seen them, possibly ever," Mason Hamilton, an analyst with the Energy Information Administration said of propane prices during a January 24 USDA radio report.

One of the reasons cited for the shortage of propane in the U.S. is that a larger-than-normal amount of propane was used in 2013 in an effort to dry grain during a late harvest.