Thank you for your question that has just been sent to me, regarding your Pit bull boy Mojo who has an ongoing, ulcerated mass on the skin of his abdomen. It certainly sounds like you have done all you can to deal with this mass alongside your veterinarian, and good on you for attempting to have the mass removed. It is now a matter of palliatively dealing with this mass so that it doesn't bother your boy, and doesn't create too much of a mess as it bleeds.
You are certainly doing the right thing in keeping this ulcerated mass as clean as you can and the iodine wipes are ideal. You could also try some simple salt water as well. Often this can be enough to help dry an ulcerated area out enough to help stop the amount of ooze from the area. As the mass can't be removed, there will always be ongoing areas of ulceration and discharge from the mass, but hopefully you can limit this with some salt water bathing, alongside the iodine and topical antibiotic. I would also suggest that you look in to some activated manuka honey as well. This can really help ulcerated areas like this granulate over, and again, this may help to limit the amount of 'ooze' coming from this mass. You can read more about the use of this honey in these types of wounds online HERE and buy it from places like THIS .
Finally - I would also suggest that you simply place an absorbant dressing on this area and replace this once per day. Your vet will be able to supply you with a box of dressings (for a fee of course - but they generally aren't too expensive). He or she can than show you how to apply and remove these dressings. A common dressing that would be ideal is a 'Primapore' dressing. The dressing will help to limit the amount of discharge coming out around your home, but also help to keep the topical meds (honey and/or antibiotic) that you are applying on the area for longer.
Best of luck with Mojo. These masses can be frustrating, but it is a matter of managing this the best you can so that Mojo is comfortable, and so that your house doesn't become a mess. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
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