Lump on dog

Noticed this on my dog today. He is still eating and it seems soft. 

Hello!  I trust that you are referring to a lump on your dogs' testicle / scrotum.  Unfortunately, the hair around the scrotum is arranged such that I cant see whether there is a matching lump on the opposite side.  Testicles do have a normal lump called an epididymis, where the start of the sperm-tube meets the testicle.  If that is the case, there will usually be a matching one on the other testicle.  However - and especially if the two sides feel different - we reccommend that you get this checked by your vet.   If this is not the epididimis, it could be an inflammatory, infectious, cancerous or benign growth either in the scrotum or testicle and these should be picked up sooner rather than later.  They sometimes need to be tested before your vet can say for sure.