A. When cats fight they scratch and bite, very often they will get injured and an infection in a form of abscess will form, these abscesses are not always clearly seen, but usually the area will be quiet swollen. This can cause fever, lethargy and diarrhea.
Take him to your vet, he will probably find the infected sites, he will give your cat antibiotics and possibly pain killers. Sometimes the abscess need to be lanced and drained as well.
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