A. The abscess sounds like it opened and drained on its own. Occasionally, you get lucky and these get better on their own. That is not usually the case. Since a vet visit is not possible for you at this time, look him over carefully for any sign of the wound and wash it if he will allow you. Monitor the area every day for swelling or return of the discharge. If the infection does not completely resolve on its own, these symptoms will return and antibiotics would be necessary. I would recommend that you try to plan to have him neutered soon if you can as this may help reduce his fighting interactions with other cats.....these fights usually lead to infections and abscesses. There are a number of low cost spay and neuter options becoming available and your local humane society or animal control may be able to recommend one for you.
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