Cat Breeding

Breeding Systems

A pedigree cat is one having both parents of the same breed. A breed is a group of cats with common characteristics which distinguish them from other groups. The following is a brief summary of some breeding systems (for further details, consult a book specializing in breeding systems).


Inbreeding is the mating of very closely related cats, such as father and daughter, mother and son, brother and sister. This type of breeding is not recommended for the novice cat breeder, since many undesirable traits may be produced. It is used when there is a desire to accentuate certain characteristics in the offspring.

Line Breeding

Line breeding is the most common and reliable system of breeding cats (and other animals). It is similar to inbreeding, but the animals are not so closely related—for example, mating cousins with cousins. Inbreeding and line breeding tend to concentrate characteristics, whether they be good or bad; great emphasis should therefore be placed on the selection of animals used in these systems. Bad features can be just as firmly fixed by these methods as good features.

Out Crossing

Out crossing is the practice of mating unrelated or remotely related cats within a breed.

Cross Breeding

Cross breeding is mating a pedigree cat with a pedigree cat of a different breed. When this is done scientifically, new breeds are established.


In the male both openings are round and separated by the swellings of the testes. In cats older than two months the testes can be felt. In the female the openings are closer together and resemble an upside-down exclamation mark. In the male the prepuce, which is the bottom hole, can be pulled back on both sides to expose the tip of the penis. Similar examination of the female reveals a vertical slit, rather than a circular hole.
Any cat that is not to be used for breeding should be desexed, whether it is male or female. Male cats, after reaching maturity at six months, develop a very offensive urine odor As it is their nature to spray their environment with urine (called ‘marking’ their territory), and this can include furniture in the house, they can be unpleasant to have around. Undersexed males may also roam looking for queens (female cats) on heat, leading to territorial encounters with other male cats and inevitably fights, which result in injuries and abscesses.
Female cats, if not desexed, will come on heat each twenty-one days until they are mated. While on heat they can be particularly vocal and sexually active. A cat may have up to twelve kittens a year if left undersexed, which means you are faced with the problem of finding twelve homes! Desexing of both toms and queens should take place before they reach sexual maturity, at five to six months. Desexing does not alter the cat’s personality, nor does it cause obesity. A desexed female or a desexed male makes an equally good pet.

The Female (Queen)

The queen is generally sexually mature at six months of age. While the male cat is interested sexually for the whole year, the female is sexually interested only when she is in season. This occurs at fourteen-day intervals and usually lasts for three to six days. It may be prolonged for up to ten days if mating does not occur. The two main breeding seasons are spring and summer but the cat may cycle at other times of the year.
Compared to the dog, the cat shows few physical signs of heat (such as swelling of the vulva or vaginal discharge). Behavioral changes, however. are unmistakable.
The queen on heat shows the following signs: increased restlessness (she may be absent for days at a time, if not kept confined); increased vocal activity, particularly in the- Siamese breed; affectionate behavior towards owners; constant rolling and crying; hollowing of the back; raising of the hindquarters; deflection of the tail to one side; treading movements of the hind legs
Ovulation in the queen does not occur automatically when the follicles _ pen in the ovary, but requires some stimulus to trigger it off, such as mechanical stimulation of the cervix. A fairly prolonged period of courtship I three or four days) is necessary to stimulate the follicles to ripen to the point of rupture. During the courtship period, the female will reject male advances; then follows a period of about twenty-four hours when she will accept service from the selected male (or males) several times.
In contrast, lactating queens, which usually come into heat within a few days of giving birth, will disappear briefly and accept service without the courtship period. These matings are usually fertile and account for the feline species’ ability to proliferate. It is important for people already saddled with an unwanted litter to remember that the cat can become pregnant again while lactating. Desexing three weeks into the lactation period will not dry up the mother’s milk.
During mating, the male grasps the loose skin of the scruff of the female’s eek with his teeth; this seems to be an essential part of the mating ritual. Because of the anatomical arrangement of cats’ genitalia, the full cooperation of the female is essential for mating. Estrus behavior continues for twenty-four hours following mating, though a male is no longer accepted. Because a change in environment can affect the virility of the male cat, it best to bring the queen to him.

The Male (Tom)

Sexual maturity is reached in the male at about eight months. Toms under six months of age may show sexual interest, tussling with another kitten (female or male), mounting its back and perhaps simulating sexual motions. When a female on heat is nearby, the torn will cry and try to get out of the house to reach her. He may spray foul-smelling urine around the house. This is normal behavior; an expression of his sexual ability and an advertisement of his availability.
Impotence is rare in the cat. Lack of virility can be caused by a vitamin A deficiency or a change in environment. Vitamin A deficiency can be corrected by two or three drops of good-quality cod-liver oil in the diet daily.
A male cat in which one or both testicles have failed to descend into the scrotum is known as a cryptorchid. Where both testicles are undescended. the cat is usually sterile. A male cat in which one testicle remains undescended is known as a monorchid and is usually fertile. Cryptorchidisn: is regarded as an hereditary abnormality. These cats should be desexed. Any torn that is not going to be used for breeding should be castrated to prevent roaming, to eliminate the strong odor of the urine and to prevent unwanted kittens. Desexing also tends to make the male more docile and softens his appearance. It is best done at six months of age.

Failure to Cycle

Failure to cycle has several causes, the main one being nutritional deficiencies. Deficiencies of vitamin A and essential fatty acids are more common than is generally realized Iodine deficiency is seen in cats on a mainly meat diet.
Illumination is important; it is recommended that breeding queens should be exposed to at least fourteen hours of light in each twenty-four, preferably a combination of daylight and artificial light. Contact with regularly cycling queens also promotes estrus.
‘Silent’ estrus is a newly recognized condition found in cats that are normally allowed to leave the house but kept confined during estrus periods. Such queens develop the ability to conceal their status until leaving the owner’s area of control and observation.
If fertilization does not occur after ovulation, a state of pseudo-pregnancy lasting thirty to thirty-five days follows. This is not easily recognized, because the cat is perfectly normal but simply fails to cycle.