“Generally, energy intake must increase by 1 percent for each degree of cold below the LCT.”
Lower critical temperature is influenced by an animal’s size, age, breed, nutrition, housing conditions, and hair coat or wool thickness. The thicker the hair coat or wool, the more the LCT decreases, he said.
But, Lewandowski cautioned, with a wet hair coat, the lower critical temperature increases to 59 degrees for cattle, horses and goats regardless of how heavy its hair coat is because hair coats lose insulation ability when wet. Sheep wool, however, is able to shed water, he said.
The lower critical temperature for beef cattle, dependent upon the development of the hair coat, is:
- Summer or wet: 59 degrees
- Fall: 45 degrees
- Winter average hair coat: 32 degrees
- Winter heavy hair coat: 18 degrees
The lower critical temperature for goats is generally considered 32 degrees and for sheep, 50 degrees, he said.
“For most livestock, it really is a matter of adapting to the weather,” he said. “Cattle will adapt to cold with a thicker coat if they have the feed source.
“If the animal is in poor body condition or doesn’t have a good winter coat developed, producers may have to supplement it with higher energy feed and get it out of the wind to get the animal through the weather.”
Another measure producers can take to care for livestock in harsh winter weather is to ensure the animals are blocked from the direct force of the wind to help protect them from wind chill, Lewandowski said.
Producers whose animals don’t have regular access to a barn can:
- Provide windbreak protection to reduce the effects of wind chill on energy requirements.
- Increase access to better quality forage. Livestock can increase intake to some extent under cold conditions and if forage is of good quality, then energy intake is also increased. With poorer quality forages, grinding to decrease particle size can allow more intake and increase digestibility.
- Limit feeding of corn, or use of a high-energy, non-starch feedstuff.
Move livestock out of muddy conditions or take steps to reduce the mud by using a feeding pad.