A rumination on shelter
When I say we raise our sheep on pasture it means that although they have access to rudimentary shelter (open quonsets, see below) they spend all of their lives out-of-doors. None is ever in the barn except on the rare occasion that a ewe encounters a difficult lambing. Occasionally someone who hears this will wonder about the wisdom of such a practice and ask whether the animals would be more comfortable inside, especially during winter. Our rationale is based on ruminant digestive metabolism and the generally unhealthy conditions characteristic of big, production, barns. So, how does the fact that sheep are ruminants reflect on the wisdom of raising them entirely out-of-doors? The human digestive tract may reasonably be thought of as a continuous tube (open at both ends) and it helps to understand how it works by dividing it up functionally. So it is that we learn about the mouth, esophagus, stomach, small intestine, large intestine, and colon. The digestive tract of a ruminant is a bit more involved in that its stomach is elaborated into four compartments (rumen, reticulum, omasum, and abomasum) which allow it to do what none of us can, and that is break down plant material (cellulose) and ferment carbohydrate via the action of symbiotic microbes. The largest of these compartments is the rumen and it is here that plant starches are fermented to release sugars which are then metabolized by bacteria to produce fatty acids which are taken up as nutrients by the circulation. What I’m getting at is that bacterial metabolism isn’t all that efficient and it has been estimated that approximately 10% of the gross energy content of forage is given off as heat. The normal body temperature for a sheep is between 102-103ºF. Combine that with a very deep, very dense, and heavily greased wool coat and you shouldn’t have to ask if sheep can comfortably overwinter out-of-doors (and at, in our case, 41°N latitude). The most important thing that a shepherd can do to successfully raise sheep on pasture is to provide a hay supply ample enough to keep their bellies full. I captured the photo above the other day. We were expecting temperatures in the low single digits and rain changing to freezing rain and snow by morning. I was very happy to see the girls tucking in. I remember, when we were living in Indiana, when it got down to -30ºF (-34ºC) one night. I was sure that all of the sheep had perished so suited up to go out and survey the damage. In too much of a hurry to turn on the light I jumped the fence. As I approached a collection of silent, stationary, masses I switched on my flashlight. I startled every last one of them where they lay. They looked up … and blink, blink, blinked the heavy sleep from their eyes. If they could have spoken I am sure they would, in unison, have said, ‘Turn out the light! Can’t you see we’re trying to sleep?‘ As I made for the house I felt a little sheepish for having disturbed them from their deep and comfortable slumber. Having allayed your fear of sheep living on pasture I can also tell you that even the most fastidiously managed barn isn’t a very healthy place for your sheep, no matter how good it’ll make you feel to have them in when it’s cold and blowing outside. One of the facts of farm life is that all animals produce manure and a stall or pen, when left unattended even for a day, will accumulate manure and urine which harbor bacteria, ammonia, and moisture … a combination which, when ventilation is poor, can lead to the development of respiratory illness and pneumonia. Having said all of that, providing some sort of shelter for your animals, even if it is only rudimentary, is critical. Animals do well in the very cold as long as they are dry … they do well in the rain as long as they are warm … but a very dangerous combination, especially for newborns, is wet and cold … and more so when the wind is up. One of our first priorities has always been the provision of ample room undercover for all of our animals to shelter from such dangerous conditions. Our sheep also don’t do well in very hot and humid conditions; here too shelters are critically important. Here’s a link to a site showing the Port-a-Hut Livestock Shelter. We use the 8′ wide version here at the farm. POSTSCRIPT: As I composed this post I took a minute to check the forecast for the coming week. A front will be moving through our area on Monday. In its wake we are expecting rain, sleet, ice, and snow and temperatures approaching 40ºF at midday to -5º overnight. All I have done to prepare is put out a fresh round bale and I know that the girls will be just fine.