Popcorn time LOL.. I let the experts answer that...

They put animals in cage with catch pan underneath it is the simple answer of how.
Test on your dog is a good starting test of quality. Once you've smelled the real undiluted stuff you will know the difference. One of the safer way is to only buy from someone that collects it themselves.

I use both fox and coyote pee on our line, and for change up I reach for bobcat or mink pee.
Post sets, or the second hole of a double dirthole set.
I've caught coyotes and fox on all four types of pee I use. Also fox and also cats.
At coyote set remakes, bait and either fox or mink pee seem to work really well for me.
At those post sets a smear of beaver castor also works really well by itself.
Jim

I'll sometime use both at a set, sometime both with a shot of bobcat urine. I've had good responses. Curiosity? Territorial? I don't know.

I don’t catch many coyotes at sets that don’t have urine. On the flip side I also get a lot of deer sprung traps. This year I ran a little test. I didn’t use any urine for the first week. Didn’t catch any coyotes. After a week I freshened everything up with urine, started catching coyotes the next day. I haven’t noticed a difference on coyotes whether I use fox, bobcat, or coyote pee.
Now this was a very unscientific test. My lack of catches could be attributed to anything. It could also have something to do with the confidence factor as well. I just know that urine equals catches for me.