Is there a scent, or a combination of scents, that repels dogs, whitetails, and cats? If such exists, please identify. And if such exists that will last a long time, that's even better.

About the only thing I thought might repel all would be human urine. But I have found instances where human urine appears to be an attractant.

Many things have been tried but none work all the time.

A .22 never fails if used right.
George

I use "Obama repellent spray" works like a charm!

Spray things and places where they go, with ammonia .Replace as necessary.

Pee of any kind is an attractant. Its the #1 way critters communicate, their version of shithouse graffiti if you will! I've heard of boiling the hottest peppers you can get your hands on and spraying that or commercial pepper spray, may work at first. Unfortunately animals seem intrigued by anything and everything smelly.

Irish Spring soap seems to keep deer out of bushes around the house

I have hung dirty socks around my aviary pens to repel wild k9's. This did work but once rained on you need to replace them. I would think an old sweat drenched shirt would work too.

I use dehydrated rotten egg to prevent deer from eating Christmas trees. It comes in 50lb bags and I mix it in a mist blower at a rate of 100lb egg with one quart of Bond Max sticker per 170 gallons of water. Will usually last a couple of months. The egg doesn't bother dogs, don't know about cats; don't have them any round here much. I control them another way.

God Bless, Louis