How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask John Taylor Your Own Question
John Taylor
John Taylor, Dog Veterinarian
Category: Dog
Satisfied Customers: 106
Experience:  MA VetMB MRCVS
Type Your Dog Question Here...
John Taylor is online now
A new question is answered every 9 seconds

I noticed a large hard knot under my dogs skin on his back

This answer was rated:

I noticed a large hard knot under my dogs skin on his back towards his right hip. There was a scabby area in his hair so I shaved the area to get a better look. As I was scratching off the scabby residue, it suddenly erupted with pus and a black granular discharge. He didn't appear to be in pain and as I massaged the knot gently, I was able to work out a substantial amount of the black stuff; however, it wasn't always grainy. It was oily and more solid...almost like a black head in people. It continued to alternate between pus, black grainy discharge, and this solid oily black substance until the knot was all but gone. The next day, I checked it and it had a little more pus and clear fluid but now, a few days late, there is no knot and only a small scab remaining. Should I be concerned or did my dog just basically have a pimple?

This sounds like it could have been an abscess, though this is generally painful, or more likely a sebaceous cyst:
(apologies for pop-up, it's otherwise a good site)

They're generally not a problem but can fill up again. It's great that it seems to have resolved; keep a close eye on it and if it becomes infected or painful then you should get it checked out to make sure there's nothing more sinister behind it.

Good luck

John Taylor and other Dog Specialists are ready to help you

Related Dog Questions