He's just excited because you have a sausage in your pocket.

Also does it when I've been around another dog. It hasn't been an issue with my wife yet but if it does, I'll just tell her its another dog not another woman lol.

A quick solution...

Get rid of the dog.

If hobbying without getting caught is more important to you, you gotta do what you gotta do.

If you need help, I know plenty of restaurants in foreign countries who would gladly serve those dogs for dinner. lmao  

j/k

Actually, I do know a few friends who eat dogs. I don't myself though.

Make it a habit to play with the dog for a minute or two as soon as you get home. Then she won't notice.

Do you shower after your date? Maybe that would help. A good plan anyway. You don't want the wife to have a surprise for you when you get home, and have to explain why you need to take a shower first.

face, hands, privates...  Wife hasn't kissed me at the door for years but once she decided to & I was fresh from a DATY inclusive session.  There was no way I was letting her nose get up close & personal with my pussy-juiced face.  I made an excuse (had to run to the bathroom)...  & while I was there washed up throughly.  Came out, gave her the kiss & all was good in the world.  Lesson Learned!!  

The dog may still do it.  I know many dogs that will dry hump...  if you've even masterbated recently.  A friends poodle did that more than once when I was younger.  

If you have washed well, if wife comes in for the sniff test, she'll not smell anything if you wash well.  Neutral or unscented is best...  unless you're coming from the gym where you can explain fresh (just washed) scent.  
H