Inter-cat aggression is one of the most common welfare problems in multi-cat households, causing chronic stress for both aggressor and victim cats and frequently leading to rehoming or euthanasia when untreated.
Inter-cat aggression creates welfare costs that often go unrecognized because the suffering of victim cats is invisible. A cat chronically blocked from a litter box, food bowl, or resting spot by a dominant housemate experiences resource stress that manifests as physical illness. The victim cat's inability to predict or control social threats creates chronic psychological distress equivalent to human anxiety disorders. Many multi-cat households contain cats that are genuinely incompatible and experiencing ongoing suffering that owners attribute to 'cats being cats.' The welfare solution is rarely permanent separation (though sometimes necessary) but rather environmental management that allows cats to coexist with adequate resources, escape routes, and space.