strange lump under dogs lower jaw

Hey all, my name is Crystal and I am new here and have a question and wondering if anyone may have any ideas. I have a dog that was a stray and was absolutely skin and bones when he showed up. He was very skiddish and would not let ANYONE touch him. Well I have fed him and fattened him up alowly and my daughter and I have now earned his trust and he is very protective and we love him dearly. Now that he is trusting enough to let me hold his face in my hands I have found a lump under his lower jaw. It does not appear to be sensitive to touch, he does not whine when i touch it or move it around. I did notice him cough a couple of times tonight at feed time. He has never done this before. Does anyone have any idea what this maybe or think that I should be overly concerned with it? I have become attached to this poor dog and want to take care of him, but I am not sure if this should be a concern as he has just started letting me handle around his face. I appreciate any advice. Thanks for listening.

Crystal

What a kind person you are. You should think about having a vet look at that lump. It may be just a cyst, or scar tissue from an old wound, but it may also be something more serious. Best to be sure.

Bless your heart, Crystal.
Yes, I would definitely take him to your vet. Since you know nothing of his history, it would be good to get him checked out in any case. Your vet could also test for heartworms (a simple blood test.) This can also cause coughing, underweight, etc.
It's impossible to tell you what the lump could be without a vet actually looking at it.
Please post back with what you find out!

Bless you for taking this little guy in! :) I agree with the others that a vet needs to look at this. You also need to assume he hasn't had any vaccinations and need to get him started on those. Can you tell his approximate age? I'd love to see a photo!