Most cats become sexually mature during their first year of life, and it is not unusual for a female who is little more than a kitten herself to give birth. Once sexual maturity has been reached, the female (queen) can produce a litter of one to ten kittens once a year, although some foreign breeds can give birth every seven to ten months. This means therefore that a queen is potentially capable of raising one hundred kittens in her lifetime.
Oestrus, being on heat or in season, denotes the female’s receptivity to reproduction, which signals to male cats that she is ready to mate.
Female cats begin their reproductive life when they first come into oestrus – the biological term for the behaviour we recognise as a cat ‘in heat’. This initial phase of the breeding cycle signals to toms (and owners) that the queen is ready to mate. The onset of oestrus itself is signalled by changes in behaviour, including calling, rolling and frequent rubbing. This period is followed by oestrus proper, during which the queen makes piercing calls and is restless to find a mate.
CONCEPTION AND AFTER
Unlike human females, queens do not ovulate (produce an egg) prior to mating. The egg is only released from the ovary during the act of mating. If mating is successful, the period of gestation (pregnancy) begins. If it is not successful, then the female will come into oestrus again in about three weeks time.
GESTATION AND BIRTH
Gestation in cats lasts between 58 and 72 days, with an average length of 65 days – just over two months. Some two weeks before the birth the queen will actively seek out and choose a place where she will have her litter. This will be somewhere that she feels is safe and quiet. Following the birth the kittens will suckle their mother’s milk for six to eight weeks. Oestrus will resume two to three weeks after the kittens have been weaned, and the whole cycle will begin again.
- The head of the male’s penis is covered with horny spines. These stimulate the release of an egg from the ovaries (ovulation) during copulation.
- Cats can breed throughout their lives, but queens should not be mated after 7 years old.
- Queens may mate several times with different toms during oestrus, and as a consequence may give birth to kittens that have different fathers.
Q. I was told that female cats can be put on the pill. Is this true and is it advisable?
Yes, it is true, but it is only really recommended in special circumstances, as it can have serious side effects when given long term. Owners who want to avoid pregnancy are better advised to have their queens spayed.
Q. How long does cat oestrus usually last?
It usually lasts for about 10 days, but if the queen is mated and ovulates, it is more like 4 to 6 days.
Q. When does a cat become sexually mature?
In some breeds, sexual maturity can occur as early as 3 months, but the more usual onset is between 7 to 12 months for a queen, and from 10 to 14 months for a tom. Feral cats generally take longer to reach sexual maturity, at between 15 and 18 months.