Nikki had something almost identical and it was a ruptured anal gland. I took him to my vet that day and they had to clean out the anal gland and instill antibiotics in there and gave him an oral antibiotic and pain meds. I had to take him back within a week for another treatment. He healed up nicely, but it is important to get them in as soon as you see it. I was told it is more common in males. My sons male had the same thing a couple of months ago. I hope you got Max in and he heals quickly |