There are several reasons for this - first, is the winter coat. Snow that falls on the backs of our cows doesn't melt. This is testament to its ability to retain heat. Second, cattle are far larger than humans. Heat is lost through the skin (duh), and the more surface area of skin one has the greater that rate of loss. As the size of a body increases the surface area to mass ratio decreases. That means the larger one is, the better one will hold onto heat. There are other confounding factors like the shape of the body in question, but here again cattle have humans beat. Humans have long legs and arms, which add significantly to surface area without doing much for total mass. A good example of this basic principle can be seen in the deer family. Moose, elk, and caribou are all quite a bit larger than the white-tailed, black-tailed, and mule deer that live to their south. Their tropical cousins take on even more diminutive statures, some species at maturity only grow as big as dogs. A third advantageous cold adaptation that cattle have over humans is the rumen. One need only look at the steam rising from a composting pile of leaves on a cold fall morning to recognize the embodied energy in plant matter. Cattle eat A LOT of vegetation, literally composting piles of matter inside their bodies every day. That breakdown process releases many, many calories, which keeps our cows warm from within.
All this is not to say that cattle are immune to the cold, merely that they are comfortable out in it so long as some minimum requirements are met. There are factors that can make them uncomfortable though. Strong cold winds can cut through their winter coats and whisk away much of their warmth. Consecutive days of cold, wind driven rain in the autumn before their winter coats are fully in place can chill them. Running out of feed also shuts down their internal furnaces. These conditions can be accounted for with good management. Our one fenced pasture is a long triangle, the narrow end of which is well sheltered from our prevailing westerly winds by a steep little section of hill and some trees. There are other spots on the farm that are even better sheltered, but they don't have encircling fences yet. We provide them with free choice hay, as much as they can eat every day. There was one day back in the fall, late October, when it howled with cold rain for hours on end. I did bring the herd inside for 22 hours then since the steers were smaller than now, and I didn't trust their winter coats were thickened all the way out.
So why do we want to out-winter in the first place? Is there a point to keeping an eye on the weather and adjusting the cattle routine based on conditions outside? Why not just do like most other people and put them in the barn all winter?Here again I have a number of reasons I find outwintering appealing. I don't like hauling shit. Poop stinks and it gets on everything. Some progressive leaning farmers compost the winter's manure and bedding pack before hauling it back to the fields. But that still requires one to be a tractor jockey. Every bit as important as avoiding the smelliness aspect of the manure wagon is the avoidance of machinery. When I fire up my tractor I can literally see the entropy pouring out the exhaust pipe in a roil of disturbed air and incompletely burnt hydrocarbons. Burning petroleum and moving metal does not constructively contribute to my larger goals if I can find a way to do the same thing without turning a key. I don't have extensive experience with cattle, but I like the healthfulness of fresh air. Cow barns can be kept clean and odor free by conscientous farmers, but it takes more effort than having the great outdoors do all the work. Barns that aren't cleaned consistently stink of ammonia from the animals' urine. I believe it makes both them and their owners sick to live and work in ammonia laced air. Walking around is good for mammalian bodies. It keeps muscles toned, and hooves worn down. Cows that stand too much need their hooves trimmed back, while outside cows usually wear the hoof away as they amble about.
So, if you feel compelled to worry about our cattle allow me to recommend that you get anxious that they'll be killed in a terrorist attack, poisoned by a psychopath, or carried off by harpies. I promise, we've got the cold situation under control.
-Edmund
