The bitter cold is a challenge for cattle ranchers who need to ensure animals are getting enough nutrition to generate the extra energy needed to stay warm.

Agriculture experts and ranchers know that when the temperature dips below -20 C, cattle need to eat more.

"Most years the average hay out there is good enough to maintain a cow in wintertime," according to Murray Feist, a ruminant nutrition specialist with Saskatchewan Agriculture. However, when there are extra demands on the body, the animal will need extra food.

Cows that are pregnant or are providing milk for a calf will need more food. As will all animals facing very cold weather.

"Once we get into these really cold, cold days, we have to add a different form of energy into the diet," Feist says. For most, the choice is a grain feed. "It's got a considerable amount more energy per pound than what you would get from a feed like a hay."

Feist says there are other factors to consider, such as shelter from the wind.

The general rule of thumb is to feed an extra pound of grain for every five degrees below -20 C.

Much of Saskatchewan was in a deep freeze Monday with temperatures near or below -30 C and wind chills colder than -40 C. At one point in Regina, it felt like -47 C with the wind chill.

"When we get down to temperatures of the -30s, and you know -50 with the wind chill, those cattle feel the cold pretty quick, so you really have to be able to adjust and accommodate for those temperatures by feeding a certain amount of grain," said Feist.

But getting cattle through the frigid weather is not as simple as just feeding more grain. Ranchers also need to be careful to avoid "grain overload," known as acute acidosis, said Feist.

"They have to split it up into a morning and an afternoon [feeding]," he said. "That can help them avoid getting into some digestive upsets by overfeeding too much grain."