Although female cats and neutered male cats can spray urine, un-neutered male cats are the most likely to engage in this behavior. To better understand the behavioral aspects of cats that spray urine, a distinction should be made between spraying urine and urinating somewhere other than the litter box. Male cats are likely to spray urine as a response to a fearful or frustrating situation, to mark their territory or to announce their sexual availability.

It is very common for un-neutered male cats to spray urine to let other cats know he is ready to mate. The male cat sprays urine as a normal response to the sex hormones that develop in his body at about six months of age. If a female cat will ever spray urine in her life, she is usually most likely to do it if she is in heat in order to attract a male cat.

Territorial spraying may occur as a response to stress about losing territory such as when a new animal enters the home. It is common for male cats to spray urine frequently when they are in a multiple cat household. Just as it is normal for cats to scratch as a way of claiming their territory, it is also normal for them to spray urine to mark what they claim as theirs.

Sometimes, a cat will spray urine on certain items out of anger or frustration. If a cat is suddenly left alone after being used to spending most of his time with people or other cats, he may react by spraying urine. It is not really about retaliation, but is a cat's normal response to change and stress. If a cat becomes fearful such as if a large dog suddenly joins the household, he may also react by spraying urine.

A cat does not spray urine toward the floor as he would when urinating regularly. Instead, the spray will be directed at a wall or other object. If the cat's litter box is dirty, he may urinate downward onto a rug or other surface. That is not the same as spraying urine.

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