Changes

==Typical Causes==

==Typical Causes==

* '''Loss of core territory facial or flank marks''': Usually due to redecoration or change of house.

* '''Loss of existing facial or flank marks in the home''': Usually due to redecoration or change of house.

* '''Loss of maintenance of group odour''': Temporary or permanent loss of a social facilitator cat, absence of the owner, or housing of group members apart (at a cattery) so that odour is not mixed between individuals and factions.

* '''Loss of maintenance of group odour''': Temporary or permanent loss of a social facilitator cat, absence of the owner, or housing of group members apart (at a cattery at at the vet clinic) so that odour is not mixed between individuals and factions.

* '''Failure of odour recognition of a specific individual''': Individual odour may be altered or lost if a cat is taken away for grooming or veterinary treatment such as dental work. The cat may also return home with the odour of an unfamiliar cat on it. The returning cat may be regarded as an intruder. This causes aggression or the cat may never regain its previous role in the social group.

* '''Failure of odour recognition of a specific individual''': Individual odour may be altered or lost if a cat is taken away for grooming or veterinary treatment such as dental work. The cat may even return home carrying the odour of an unfamiliar cat on it. Failure of odour recognition can lead the returning cat to be regarded as an intruder by the other residents. The resulting aggression may prevent the cat from regaining its role in the social group.

* '''Introduction of a new cat''': This may exceed the population that can be supported by existing resources, or the new cat may upset existing social relationships (through despotism, competition or by increasing stress in the group). The same effect is apparent when a recently introduced kitten reaches maturity.

* '''Introduction of a new cat''': This may exceed the population that can be supported by existing resources, or the new cat may upset existing social relationships (through despotism, competition for resources or by increasing stress in the group). The same effect is may be seen when a recently introduced kitten reaches maturity and becomes a potential competitor for resources.

* '''Illness''': Conditions that alter the cat’s emotional state or interaction with other cats ([[Hyperthyroidism|hyperthyroidism]], senility, pain, hyperaesthesia, debilitation) or need for resources (conditions causing polydipsia or polyphagia).

* '''Illness''': Conditions that alter the cat’s emotional state or interaction with other cats ([[Hyperthyroidism|hyperthyroidism]], senility, pain, hyperaesthesia, debilitation) or need for resources (conditions causing polydipsia or polyphagia).

* '''Excessive population density outside the home''': existing overpopulation, new cats introduced to an area, or when a cat owner moves a group of cats into a new home in an area where many cats already live.

* '''Excessive population density outside the home''': In areas where there is already a high population density of cats this can restrict resident cat's ability to use outdoor resources, and brings non-resident cats close to the home. Resident cats will use spray marking in an attempt to maintain distance from other cats that they see around their territory.

* '''Unfamiliar odours brought into the house''': non-resident cats may spray close to a front or garage door so that this odour seeps into the house. Owner’s shoes, clothing or bags may pick up odours from outside.

* '''Unfamiliar odours brought into the house''': non-resident cats may spray close to a front or garage door so that this odour can come into the house; owner’s shoes, clothing or bags may pick up odours from outside.

==Diagnosis==

==Diagnosis==