[haggis]

My 12 year old Yorkie "Haggis" has developed a large lump on the left side of his bottom. He had been fine until yesterday when I noticed this, although he had been straining to go to the toilet but this occasionally happens as does the opposite.
I feared the worst and took him to the vet who diagnosed a tumor which was then revised when I told them he had been straining to poop. On investigation they discovered he had ruptured himself just behind his anus and the excrement was not escaping. he was given an enema and some laxative whilst they confer on whether he is fit enough for surgery to sew the rupture ( he has a heart murmur and a trachea problem although all under control) he seems healthy and unaffected although I am extremely concerned.
Has anyone else had a similar experience???