creamy green discharge from male dog

Question
Hi, my 13 year-old West Highland terrier has a discharge. The info I found is always referring to puppies stating it's normal, but no info on older dogs. He's not licking it.I have an apt to see his vet, but it's scheduled for tuesday. I'm worried as he's always has a very very good appetite, but tonight he didn't want to eat. I have his sister and she doesn't have anything in her privates. He's been neutered when he was a puppy, and from time to time will get an urge to mount the female but he has never managed to remotely manage it, so it's not because of that.
Any info will be greatly appreciated. I'm in the middle of moving and all my books are packed.
Thanks a lot !
Michele

Answer
Hi Michele,

It is common for males to have a small amount of discharge.

"Preputial discharge" is any substance flowing from the prepuce, which is the fold of skin that covers the penis. Often, licking at the prepuce/penis accompanies the discharge, so the terms interchangeably.

Preputial discharge may consist of blood, urine or pus. Having a small amount of whitish-yellow discharge called "smegma" is normal for a dog. Smegma is the normal sloughing of cells and accumulation of debris.

But smegma also provides nutrients for bacterial growth.
If your dog's discharge is really greenish in color, and you've never noticed discharge of that color before, it's likely the discharge is caused by bacteria, and dog has an infection which can be easily cleared up with an antibiotic.

You'd need your vet to confirm the possibility of an infection, and to provide medication.

Regarding the mounting behavior your neutered male dog sometimes displays: mounting isn't always sexual, it can also be a sign of dominance.

I hope I've been a help.
Best of luck.

Patti