Queens vary in the age at which they first go into heat. Some breeds (such
as the Siamese) may have their first heat as early as 5 months. Others,
particularly the longhaired breeds such as Persians, are not sexually mature
until 10 months or older.
Cats are seasonally polyestrous. This means they will
have repeated heat cycles over a year unless they are bred, and the heat cycles
are influenced by the seasons. The mating season in cats is determined by a
number of factors, including the length of daylight, environmental temperature,
and the presence of other cats.
Heartworm disease, so named because the adult worms live in the right side of
the heart, is common in dogs, less so in cats. In fact, cats may be
accidental hosts only, and certainly they are less perfect hosts for this
parasite than dogs are.
When there are 12 hours of daylight and other conditions are optimal, the
hormonal system is activated, and the queen begins the estrus cycle. The mating
season of cats in the northern hemisphere is from March to September. Cats in
the southern hemisphere cycle from October to March.
Throughout the breeding season, queens go into and out of heat several times
but do not always display estrous behavior at regular intervals. Often they exhibit
continuous heat cycles in early spring (averaging 14 to 21 days from the
beginning of one cycle to the beginning of the next), followed in late spring
by cycles that are further apart. Each queen establishes her own normal
Since cats are considered to be primarily induced ovulators (the physical
act of mating causes them to ovulate), a cat will continue to cycle unless she
is bred or the daylight factor takes over.
This stage of heat is the first, lasting from one to two days. You may
notice that the vulva enlarges slightly and appears somewhat moist, but this
usually is not apparent. The queen shows increased appetite and restlessness,
utters short low calls, and displays more than usual affection for her
At this time, she begins to attract toms-but refuses to mate. She may urine
mark around the house. Proestrus has been described as a period of courtship
during which exposure to the male acts as a hormonal stimulus that brings on
full heat. This belief stems from the observation that in feral cat colonies,
where male companionship is common, the conception rate is higher than in
catteries, where courtship is less spontaneous.
If you do not want your queen to become pregnant, take steps at the first
sign of proestrus to prevent unwanted pregnancy.
The second stage is the period of sexual receptivity. It is what breeders
refer to as heat and lasts four to six days. The queen begins to make more
noise and her meows are louder and more frequent-eventually becoming almost
constant. There is an obvious change in her behavior: She becomes much more
affectionate toward people, weaves in and out of their legs, rubs against them,
shakes her pelvis, and rolls about on the floor. If picked up when rolling, she
may grab at your arm or even bite.