lolI got a news flash for you. Most farmers aint GOT a barn big enough to enclose the entire herd. Nor do they always have enough hay, grain or water to KEEP the cattle near the house. When cattle get thirst or hungry, they get NOISY. All the mooing is going to callin a LOT more of an attack than virtually anyone can handle. If the shtf suddenly, the farmer will have all he can do to grab up SOME of his livestock, and try to get other stuff gathered up. Having a lot of livestock around where your family as at risk is the dumbest thing you could do.
The SMART rancher farmer will just lead off one steer to the dugout-cache area, making the beeve carry the sacks of grain to the cache area, move past that area slaughter it about a mile further on, turn 90 degrees, carry the meat another 1/2 mile, jerk it there, then haul it back to the dugout. Each time, of course, doing the work and travel after dark, while watching the backtrail by day. Take sedatives, sleep late part of night, use a little bit of speed to stay awake during the day. Good idea to have several "sets" of the jerking-strips, all up in a tree out of most critters' reach, covered with bug netting or Cheesecloth, and dipped in salt brine. This not only helps prevent rotting, it keeps the flies from laying their eggs in the meat. Shtf, smoking is out of the question.
no, the smart person isn't drugging themselves - that's a ticket for paranoia and death.
before we can know what is or is not out of the question, we would have to know the nature of the SHTF scenario, something you have never even once articulated. What is a sudden SHTF? If the power went out today, it would be weeks before things started ramping up everywhere. Most rural folks would be largely unaffected but events in a large city.
so what is it that is a sudden SHTF? Can you give even one scenario?
smoking very well may be feasible, there are ways to eliminate or severely cut down on escaping smoke. it really doesn't take a large volume of smoke to cure meat if you are smart about it.
also, whether or not cattle can be protected will depend on a lot of factors, including terrain. you don't need to put the cattle in a barn.