Found in this thread on saubier.com:
…when I was flying in to Bozeman I was talking to a real cowboy (hat, boots, drawl and all).. I asked him what they do with the cattle when its -20 degrees and such. He said “nothing”. I said “sucks to be a cow” and he just nodded.
The winter of ’69/’70 got really cold at our farm. It got down to -30 F every night for a week and never got above -20 (IIRC). The cows huddled in the deep woods which blocked the wind and only came up to the barn to be fed.
In the open the snow was between five and six feet deep with drifts twice that so that provided some shelter too.
We used an axe to chop through the ice on the pond so they could drink. We had a “calf shed with a door small enough none of the animals larger than about six months old (think young teenager in human terms) could get in. With 15 or 20 calves in the small building and some straw on the wood floor the building seemed positively toasty compared to the outdoors. They only came out for the warm milk when they got hungry.
We didn’t lose any animals and we didn’t lose any of my uncles animals we were taking care of while he and his family were on vacation (in California) during that event either.
We lost electricity for that entire week and school was closed. It was a full time job taking care of the animals, property, and ourselves. The only thing we “lost” was one outdoor water hydrant at my uncles place.