Unlike the dog, which comes into season — or oestrus – predictably twice a year and almost always at the same time for the same length of time, the cat is almost totally unpredictable. Experienced owners and breeders usually have a reasonable idea when their female cats can be expected to start calling. This knowledge is essential if prior arrangements with the owner of a stud cat are to be made in anticipation of the cat being in season at the time when the stud animal is available for mating. The queen cat may call every month from early spring until late autumn, but some cats seem to continue calling almost constantly through the year whilst others call infrequently and at totally unexpected intervals.
The Siamese in full cry leaves no one in doubt about its intentions and requirements. This makes identification of the calling pattern much easier. In other cats of a more introvert nature, signs are less obvious. Changes in behaviour can often be noticed, however, and the cat is likely to show greater interest in its owner, coming up to be petted, being a little more vocal with its chirrups, purring more often or more loudly and rolling on its back to be tickled. Busy owners may miss these signs or fail to register their significance and they will then be slightly surprised to find that their female is beginning to look a little overweight, when in fact she has had an unscheduled mating likely to produce mongrel kittens.
Physical signs of calling in the early pre-oestrus stage are a slight swelling of the external vulva, increased appetite and affectionate appreciation. As full oestrus develops the cats become more restless, follow their owners around, insist on being petted and played with, and even go to doors and windows in the anxious hope that a torn cat is in the area. At this stage their appetite may diminish since they have more important physical urges to satisfy. Other signs are continuous rolling about on the floor and characteristic paddling of the hind legs with vocal accompaniment. In fact, vocalizing their requirements is a particular characteristic of cats. It includes loud mewing which almost turns into a form of talking, interspersed with occasional loud howling noises which the novice may interpret as indicating pain. The pain, however, is entirely psychological and is based on an extreme case of sexual frustration. By this time there may be a slight discharge from an even more swollen vulva, but the fastidious cat will clean this away, making detection more difficult. Unlike the bitch, which when in season may leave marks where she sits, pinkish droplets from the vulva in the cat are most unusual. It is certainly not necessary, as it may be in the bitch, to restrict the animal’s movements in the house to avoid marking carpets or furniture.
Just as the female cat has an unpredictable calling cycle, so it is difficult to be certain when calling begins and ends. Some cats will call for several days only or at certain times of the year for even shorter periods, and others may go on almost incessantly for up to ten days or even more. An unmated queen may recycle almost immediately and this of course is all part of her programme to wear down the owner’s resistance so that, in the case of a mongrel queen, she is allowed out to be mated or, if she is a pedigree, she is sent away to stud.
The problems brought about by a constantly calling cat give the best possible encouragement to owners who have doubts about neutering. Most owners soon decide to take the animal to the veterinary surgeon for the spaying operation, assuming of course that they are not intending to breed from her. It is also possible nowadays to suppress oestrus with hormone treatment, either by injection or by tablet, which is less simple to administer. This form of hormone treatment merely delays or postpones the cycle which recurs again after an appropriate interval, but it may be helpful when having a calling queen is inconvenient, perhaps during a busy show season for the owner, or when the owner is away on holiday and the animal is being cared for by a neighbour whose tolerance to the calling phenomenon may be less sympathetic.