Baby, It’s Cold Outside!
As Floridians we are generally not used to colder temperatures. Anything below a balmy 70 degrees sends me rifling through my closet looking for scarves and a heavy coat. I’ve even been known to don long johns when the mercury reaches 50.
Fortunately, our livestock are much better equipped to weather the weather than we humans are! Livestock begin to put on a winter coat in response to a decrease in day length in the late summer and early fall. When temperatures drop, the individual hairs of their coat will stand up and create an insulating air pocket around them, trapping body heat. Ruminant animals like cattle, sheep, and goats also produce additional body heat through the process of digesting forage. So long as the animal is dry (a wet coat has a harder time fluffing up) and has access to plenty of forage, they can comfortably withstand far colder temperatures than we typically experience in Florida.
The Comfort Zone
All animals have a temperature range that is best for their overall performance, comfort, and health. This ideal temperature range is called the thermo neutral zone. The lower range of the zone is referred to as the lower critical temperature or LCT. Animals will experience signs of cold stress when temperatures fall below the LCT. At this point their metabolic rate must increase in order to regulate their body temperature.
For beef cattle or goats in a moderate winter coat, the LCT is 32 degrees Fahrenheit. With a heavy winter coat, the LCT drops to 18 degrees. Horses have an LCT of 18 degrees with a winter coat and 41 degrees with a summer coat. No matter how thick the coat, if it gets wet, the LCT increases to 59 degrees Fahrenheit for all species except for sheep. Once the hair becomes wet the capacity of that coat to provide warmth through insulation is significantly diminished. Wool reacts differently to water which is one of the reasons that wool socks do such a great job of keeping our feet toasty and dry and explains why the LCT of sheep is less influenced by moisture. Does the LCT that mean livestock can’t thrive outdoors in below freezing temperatures? Of course not! They just need extra nutrition to help them along on really, really cold days. In general, livestock will need to increase their energy intake by 1% for each degree that the mercury drops below their LCT.
Of course, not all animals can be kept warm enough with extra groceries alone. What about those who have had their winter coats shaved down, very young or very old animals, or animals like pigs who don’t have much coat to begin with?
To keep them comfortable in warmer winter weather, many horses have had their coats removed through body clipping or grooming. In these cases, it may be necessary to use a blanket or turnout rug to help them conserve body heat. Always use a blanket that fits well and check for rubs and sores if it is going to be worn for multiple days in a row. Never blanket a wet horse and always remove blankets once temperatures rise.
Pigs should be provided shelter from the wind and rain and given hay or straw to bed down in. They will often use their snouts to make tunnels in the bedding, creating their own insulation pockets for warmth. Who needs a thick winter coat when you’ve got pig smarts?
Use Heat Lamps With Care
You may be tempted to use a heat lamp to provide additional warmth to your stock. Heat lamps can be useful, but they can also present a significant fire risk. It is a good practice to reduce your need for heat lamps by using windbreaks and bedding strategically instead. Still, if you must use them, be sure to buy only high-quality lamps, labeled for outdoor use. Any heat lamp used in a barn setting should have a guard over the bulb. Use bulbs under 250W and avoid those made of thin glass that can easily shatter. Secure your lamp using both a clamp and chain in an area inaccessible to stock. Bailing twine is good for almost every job on the farm – but securing heat lamps is not one of them. Use an arc-fault interrupter breaker, install a smoke detector in the barn that can be heard from the house, and always make sure you have easy access to a fire extinguisher in working condition.
Keep Them Drinking
The final, and arguably most important consideration, when caring for stock in cold weather, is making sure that animals keep drinking water. Water is the most important nutrient and is needed for a myriad of body functions, including temperature regulation. Additionally, dehydration can result in several health conditions, some of which can become emergency situations quickly. Check your water tanks after a freeze event and remove or break up any ice that has accumulated. Of course, even without ice, freezing cold water may not be appealing to animals that are already a bit chilled. Increasing dietary salt intake and using tank heaters are two ways that animals can be enticed to drink more even when it’s cold outside.
Stay warm this holiday season and take comfort in the fact that in a couple of weeks we will all be back to complaining about the heat!