How to help an uncontrollable stray dog with a deep cut near her tail?

Poor Cookie! I would have her seen by a vet for this wound. It sounds like from her behavior that it could be painful, and there's nothing you can give her at home for the pain. Many human pain medications are toxic to dogs and can be fatal if given. If she was bitten by that cat, the wound could easily become infected and she needs antibiotic to prevent infection from occurring. The vet can prescribe these as well. Take Cookie into a vet as soon as possible to have this wound treated so it can heal. In the meantime, you can clean the area with warm water and antiseptic soap.

Unfortunately, tail mutilation can be a complicated problem to resolve - it often requires a combination of oral antibiotics, steroids, and pain medication such as gabapentin to allow the wound to heal while also keeping it wrapped to prevent further trauma from occurring. Often, part of the problem is that there may be an underlying reason why the tail chewing occurred in the first place - a skin condition, neurologic disorder such as lumbosacral stenosis, or an initial injury may have caused Zoey to begin mutilating her tail, and it's often a vicious cycle from there. In some dogs, this can also be a compulsive behavior associated with stress or anxiety. Without seeing a vet, all you will be able to do at home is keep the tail clean and loosely wrapped to prevent further damage, but Zoey will probably need prescription medications for it to heal. You may be able to find a low-cost SPCA clinic in your area who could help.

This presentation could be due to a trauma or localized spot of skin infection (likely to be caused by bacteria). A check up, appropriate disinfection and possibly antibiotics (oral, topical or in a shampoo formulation) are needed to solve the problem. Disinfection may be started at home with very diluted hibiscrub or betadine or salted water baths (twice or three times daily). Always handle this type of wound with gloves when you touch it and wash carefully your hands. Buster collar may be useful as well to avoid any licking. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further. Please find the time to give us a feedback about the consultation as that will be used to improve our service.

Unfortunately it sounds like she need some sort of sedation in order for you to clean that wound properly. A veterinarian is needed to administer the sedation and clean the wound for you. There isn't anything safe that's over the counter for you to give your dog to sedate her at home.

That wound is very larger and seems infected. he will need to see a vet. Surgery may be needed to get rid of the necrotic tissue and get to healthy tissue. Antibiotics and keeping it clean will also be needed to treat the infection. If the infection gets severe enough and spreads, he can be become septic and deteriorate quickly. Since he is a stray you may want to contact your local human society or shelter to see if they can take him in to help

Poor girl. Infected areas on the skin that are draining puss almost always need oral antibiotics to successfully treat them. I am so sorry that you live so far from a vet but you need to find a way to get to that vet soon, despite the long travels. Until you can get her there try to get your hands on some Betadine and dilute it 50:50 with warm water to help slow down the progression of the infection. However to completely clear things up you will unfortunately need to get your vet involved. You can continue the wraps as needed, but the heat compressions aren't really necessary.

Antibiotics in the US aren't available over the counter, and cats are picky with their food so they are unlikely to eat food that is treated with medications. You can get a live animal trap and leave food in there to try to capture the kitty so it can get proper treatment.