We have a family of twinners, one old black baldie cow had five sets of twins in her life, raised 3 sets on her own, all were heifers. Three of her daughters have had at least one set of twins each, a grand daughter had a set of twins this year, coyotes got one calf out of her a couple of weeks ago.
A few years ago I watched a cow calve, she turned around to lick the calf and got a piece of the placenta in her mouth and started choking. She was throwing her head around so much I could not get close until she went down with a thud. I could not find a pulse, but did see a piece of the placenta in her mouth and in disgust pulled it out, thirty seconds later she was licking the calf as if nothing happened. I named her Lazarus.
We used to run our heifers in a pool with neighbors up on range. Went up there one day and found 45 laying along a fence. All we can figure is that they were backed up to the fence during a thunderstorm and lightning hit the fence. Ten of them were ours, but at least there were 250 of the pool left alive, so it could have been a lot worse.
One time while unloading a pot coming home from range we found a cow down and dead in the top section. I was standing there with the trucker discussing the situation when he reached down and grabbed the cows tongue, pulled it out farther than a cow's tongue should go, then shoved it back down her throat. Did this a couple of times, then we both left the truck in a big hurry with the cow breathing down our necks. She was crazy after that, so went down the road a few weeks later.