Recently, I've been reading about a lot of issues with frozen hoses and troughs. All I can say is to tell all how I get through Wisconsin winters with at least three months of often below zero weather. So here it goes. I don't know what set up everybody has out there, but I learned this several years ago, after spending ridiculous amounts of time bucketing water to fill a trough and it taking hours in the freezing cold. This is what I have and what I do. Hope it helps!
First I have an outdoor water spigot that comes up directly through the well, but is outdoors. As soon as it starts to get cold and in the thirties at night, I start disconnecting the hose and roll it up and keep it indoors. By disconnecting the hose and turning off the spigot, the water drops back down to the well and will not freeze. Even if the spigot is turned off and the hose is still connected, the water in that hose will directly freeze and freeze down through the spigot and the you are screwed until spring. Simple as that.
Since I have started disconnecting the hose and bringing it indoors, I have not had a problem with frozen spigots or hoses. It keeps on working right through the entire winter. I keep one 100 gallon tank full with a drop in heater for the two horses during the winter. I clean it out once a week and refill it usual once or twice a week. The goats have an over sized heated 30 gallon bucket in which I do the same. I keep them on separate circuit as to not blow a fuse as I know the water heater for the horses draws 15 amps. It's easy to overload a circuit, especially when the electric is exposed to water and snow.
I hope this helps any of you out there struggling with frozen water. I know how you feel, I've been there and it took me a few years and bazillions of buckets to figure it out! Good Luck!