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3Normal and problematic reproductive
behaviour in the domestic cat
Benjamin L. Hart and Lynette A. Hart
The Domestic Cat: The Biology of its Behaviour (3rd edition), ed. D.C. Turner and P. Bateson. Published by
Cambridge University Press. © Cambridge University Press 2014.
Of all domestic animals, cats are the most capable of breeding, giving birth to offspring
and raising their young without human care or intervention. In the classic example, a
mother cat that has secretly gone through parturition in some obscure location reveals a
litter of perfectly healthy kittens to the human family members after the kittens have
been born. This romanticised view of feline motherhood has given way to the more
formalised cattery operation, or the family breeder where a mother cat may give birth
to her litter of kittens in the midst of an overly concerned family audience.
In this chapter, following some general information about parturition and the care
of newborn, normal maternal behaviour is discussed along with comments about
problems with various aspects of maternal behaviour. Problems with maternal behav-
iour manifest themselves primarily as either lack of proper attention to the kittens,
resulting in inadequate care and nutrition, or cannibalism of the kittens. Of course, a
necessary aspect of reproduction is the mating, which in this chapter is dealt with mostly
in the context of intentional mating of females with selected males, in a home or
Under our watch, when disturbances in maternal care occur, such as inadequate nursing
of the kittens, we step in and supplement or take over. If a mother just refuses to groom
or look after her newborn we may bottle-rear the whole litter. Because reproduction
is the keystone of natural selection, various aspects of maternal behaviour in nature
are controlled genetically within rather tight limits, which is sometimes called maternal
instinct. The genetic link does have some variability, and when a mother exhibits
inadequate mothering, or neglect of newborn, she leaves behind few or no offspring.
Her genetic line with the imperfect genetic basis for mothering dies off. Hence poor
mothering is rarely seen in nature. In our homes or in the breeding colony, however,
where kittens have a monetary and emotional value, our intervention in helping kittens
survive does not ﬁlter out the ‘bad apples’for poor mothering from the domestic cat
gene pool. Because good mothering genes are not ﬁltered out, the result is considerable
variability in the behavioural patterns that were previously under natural selection
(Price, 1984). Within a breed or breed type, many cats are normal attentive mothers,
while others appear just uninterested in their own kittens. While a promising new
mother can make a bit of a mess while going through the experience in the ﬁrst litter,
it is generally true that mothering does not improve in poor mothers even after several
litters, revealing that good mothering does not develop through experience.
As the time of parturition nears, pregnant females become less active. A female’s
grooming starts to focus on the mammary and genital areas. The explanation for this
is that the ﬁrst surfaces outside the uterine environment with which the newborn comes
in contact are the anogenital and abdominal areas, and soon afterwards, initial suckling
28 From Kitten- to Adulthood
attempts are made. Newborn kittens have a vulnerable intestinal tract that is penetrable
by bacteria that are taken into the mouth and consumed. The mother cat, by the frequent
licking and cleaning of the abdomen, mammary area and teats, well before parturition,
probably saves her newborn from an overdose of bacteria. The mother not only
physically cleanses these areas, but she applies antibacterial saliva as well (Hart &
Powell, 1990), and thus helps the young avoid disease (Hart, 1990).
As with other mammals giving birth to litters, delivery of the newborn proceeds
through the contraction process, delivery of the foetus, and delivery of the placenta
followed by an interval before the next delivery starts. Delivery, of course, involves a
good deal of straining and cats usually lie down. They may sit up to change positions.
An interesting, and now classical, observation made decades ago was the prominence
of purring in some cats during delivery, up until contractions began, and then again
following the contractions (Cooper, 1944). Another set of observations revealed that if
a person in the family was present during delivery, crying by the mother was reduced
and she purred instead (Moelk, 1979). A recent and intriguing perspective on purring
that relates to the birth process is that the vibrational frequency of purring is 25 Hz,
which is the frequency applied to the surface area by physical therapists on humans
to promote wound healing, relieve pain and help in the repair of tendons and muscles
(von Muggenthaler & Wright, 2003). It is postulated that the same effects on muscles
and bones can occur in cats during purring. The purring of mothers while giving birth
and afterwards likely helps her to recover from the trauma, while at the same time
helping the kittens grow stronger bones. The same process might apply to purring seen
while cats are lying around after going all out in the chase for a dinner, coming back
with sore muscles and stretched tendons; purring is healing. More on purring in this
light is discussed elsewhere (Hart & Hart, 2013).
Contractions become more intense as the foetus moves rather rapidly through the
birth canal. At this time, the female often chews and breaks the foetal membranes as
the foetus appears. In fact, she may tug on the membranes, pulling the foetus through
the birth canal. After the newborn has passed through the birth canal, the mother
generally consumes the foetal membranes and begins licking the newborn rather
vigorously, which stimulates the initial respiration.
During delivery of the placenta, the mother often continues to lick the newborn and
eats the placenta as it is passed. At this time she generally bites off the umbilical cord.
The stretching involved in eating the placenta seems to cause blood vessel constriction
in the umbilical cord, and little bleeding occurs. There are times when the umbilical
cord does not get chewed off or broken. Then, human attendants at the birth commonly
intervene and tie off the cord. Between deliveries the mother continues to lick the
newborn along with her own genital region. Taking a page from Good Housekeeping,
the new mother even cleans the bedding soiled with amniotic ﬂuids.
The duration of the birth process normally varies considerably, with delivery running
from 30 to 60 min (Schneirla et al., 1963). The contraction phase that precedes the
delivery ranges from a few seconds to an hour or so. Interestingly, there are relatively
minor differences in the duration of the birth process from the ﬁrst birth process a
mother experiences and after giving birth a few times. What has been noticed is that
29Normal and problematic reproductive behaviour in the domestic cat
the experienced mothers seem to be less disturbed by the whole process and respond
more efﬁciently to the neonates in licking and retrieving those that wander off. Newborn
kittens typically begin to suckle within an hour or two after the last foetus is delivered,
as the mother lies continuously with her neonates for at least 12 h.
For the ﬁrst 2 days or so the mother lies fairly continuously with her litter, leaving
for brief breaks to eliminate and feed. These breaks become more frequent over time.
The amount of time the mother spends nursing depends on the size of the litter, taking
up to 70% of her time if the litter is large, say, six kittens. There is some adjustment
while the mother and kittens settle into a routine, and the kittens commonly lose some
weight in the ﬁrst day or so.
For the ﬁrst few weeks, nursing sessions are initiated by the mother lying near the
kittens, with nipples exposed, and licking the kittens, if need be, to arouse them to
nurse. Some kittens seem to not prefer a particular nipple, while others in the same litter
regularly take speciﬁc nipple positions (but see Chapter 2). The attachment to nipples is
not all that orderly in that kittens have well-developed outward thrusting movements
with their forepaws and often knock a littermate off an adjacent nipple.
During the ﬁrst 3 weeks after birth, the mother licks the newborns’bodies extensively.
In addition to keeping the pelage in good shape, in nature, this maternal grooming
removes ectoparasites such as ﬂeas that would have come from ﬂea pupae in the nest
(Eckstein & Hart, 2000). Eye infections in the newborn, such as conjunctivitis, may be
controlled by the mother’s licking and an application of antibacterial saliva. At the other
end of the newborns’bodies, anogenital licking evokes elimination; urine and faecal
material are consumed by the mother. A reﬂex in the newborn allows release of urine
and faeces by the mother’s licking which is otherwise retained by the newborn. This
coordinated mother–young interaction keeps the nest clean. As the young begin leaving
the nest, maternal anogenital licking stops and the young deposit faeces and urine away
from the nest, not infrequently in another part of the room if a kitten-style litter box is
not available. When eliminations do occur, mothers will usually continue to keep at least
the nest area clean.
As the young become capable of taking adult food at about 30 days after birth,
mothers may continue suckling, but become increasingly less available, and weaning
becomes complete. It is during this period when mothers with outdoor access start to
provision their young, typically with rodents brought back to the nest area.
Mothers moving their kittens from one location to another in the home is rather
classic; so classic that at least one furniture moving company has adopted the logo of
a mother cat carrying a kitten in the classic curled up posture. This kitten posture is a
reﬂexive response to the kitten being grasped by the nape of the neck by the mother.
Humans can elicit the same reﬂex. Along with assuming the posture, kittens become
relatively inactive, which makes the transport system work. This tendency for a mother
cat to shift the location of her litter in the home seems to occur in response to environ-
mental disturbances, and is reportedly most likely from 3 weeks after birth, extending
30 From Kitten- to Adulthood
to 5 weeks (Schneirla et al., 1963). Although it might be hard to imagine that in nature a
mother would move a litter often, the ingrained reﬂex in the kittens to being grasped by
the nape of the neck suggests that moving a litter has survival or ﬁtness value. Several
causes for a cat living in nature to move a litter come to mind. If she sees a strange male a
mother may quickly move the litter because he might kill the kittens, which could induce
the mother to come into oestrus again and raise kittens he has sired. Another possible cause
could be the build-up of nest-borne ectoparasites as the young become more difﬁcult
to keep groomed; moving to a new parasite-free location could be very beneﬁcial
to fast-growing young that need all the nutrition they can get. The predisposition to move
a litter must be quite strong and easily triggered in some mothers because human caregivers
often see a mother moving her litter even in a strange-male- and parasite-free home.
One other rather interesting aspect of cat maternal behaviour is the ease with which
some mothers readily adopt and nurse not only strange kittens but other mammals
such as puppies. Not much can be said about any adaptive aspect of this behaviour
because in nature, strange kittens or other mammals are virtually never present in the
nest and natural selection did not occur to produce a rejection of other kittens. Hence, a
default situation continued where good mothers take care of all young things presented.
Another aspect of maternal behaviour that would never seem to occur in nature is
seen when several mothers in the same house have given birth to kittens around the
same time. The mothers may steal kittens back and forth, even harassing the other
mother for each other’s kittens. This behaviour can even progress to the point that all
of the kittens are piled together and the mothers trade off caring for them. It would
be interesting to determine whether the mothers which do this are more closely related
to each other than those which do not.
Group rearing of kittens by more than one lactating queen is also observed in groups
of feral cats (Macdonald et al., 1987). While feral cats –the domesticated cat living
unattached to a home –have been observed to communally raise their kittens, the
occurrence of this behaviour would seem to be the result of relaxation of strict selection
for appropriate maternal behaviour in just expending resources for their own offspring,
and the emergence of non-adaptive ﬂexibility in extending the expenditure of maternal
resources to offspring other than their own. But again, these mothers might be fairly
closely related and the phenomenon explicable through inclusive ﬁtness. Further, this
might occur more frequently when food resources are plentiful and clumped in space,
allowing the relaxation of selection pressure on the individual mother to feed just
her own offspring (see Chapter 5).
Understanding deviations in normal maternal behaviour
Behaviours of mothers that create problems in the home or breeding colony fall between
two extremes, ranging from ignoring the kittens and allowing them to die to killing and
eating newborn kittens. One factor playing into the array of problems is the tendency of
31Normal and problematic reproductive behaviour in the domestic cat
cat owners to intervene and help mothers showing inadequate maternal behaviour, to
save the litter. In introducing this chapter, we emphasised that aiding the survival
of young from mothers that provide inadequate care removes the selection pressures
against the genetic basis of poor mothering. This increases the extent to which the
mothering instinct is perpetuated in the offspring of poor mothers, who then live to
reproduce at almost the same rate as the offspring of exemplary mothers.
Kittens may die of hypothermia, for example, if a mother does not remove the foetal
membranes and dry the kittens. Tangled umbilical cords may occur if kittens arrive
quickly and the mother is not highly predisposed to clean off the foetal membranes. If
a kitten leaves the nest and the mother fails to retrieve it, fatal hypothermia may occur.
If a mother does not stay with the litter as described above, hypothermia frequently
occurs. Stranded kittens can be warmed gently and presented to the mother again, but
sometimes the kittens may not be accepted, even if repeatedly presented to her.
This is a rather horrifying, if not troubling, occurrence to most people that is not
uncommon. Most confusing seems to be the observation that if one kitten is killed
and eaten, the mother may appear normal and attentive to the remaining kittens. While
often there seems to be no precipitating event, some instances that have been reported
include having a litter larger than usual, and the presence of one or more kittens that
are ill or deformed. Previous experience in being a mother does not, however, appear to
be related to cannibalism.
The most plausible explanation for cannibalism by mother cats is that killing and
eating an offspring might be adaptive under certain circumstances in nature. If a kitten is
sick from reduced resistance to a pathogen and shows signs of an infection, such as
hyperthermia and inactivity, the mother, by killing and eating it, keeps the pathogen
from building up to the point that even somewhat resistant littermates could become
sick. For this disease-control system to work, the mother must promptly remove a sick
kitten before it is incubating billions of potential pathogens (Hart, 1990, 2011). In this
way she protects the rest of the litter. Rather than just depositing the dead kitten outside,
the mother gains some additional nutrition, and will need to be gone from the nest one
less time. Because a mother’s cannibalism, to be effective, must be triggered by the ﬁrst
sign of illness, even a non-infectious disturbance of the kitten or novel odour, noise
or vibration might also trigger cannibalism.
Newborn cannibalism may also occur if a mother detects a congenital deformity.
While it is not the risk of a pathogen building up in a susceptible newborn, a behaviour
that removes a newborn that is unlikely to reproduce later in life –and be of no ﬁtness
consequence to the mother –is an adaptive strategy. Cannibalism of the deformed kitten
conserves otherwise wasted resources for the remaining normal kittens.
To bring the father, or sire, of the litter into the picture raises the issue that in some
wild felids, and domestic cats, infanticide by males may occur. This is true when males
have taken over a territory in which there is a female and her litter. Such males rather
indiscriminately kill the kittens. This act, in turn, may cause the females to come into
32 From Kitten- to Adulthood
oestrus again and the male can sire the next round of offspring. As mentioned above, if
a mother sees a strange male around, one way of avoiding this tragedy for the mother
is for her to carry the litter of kittens to a new, more hidden location. On the domestic
scene there is, therefore, a logical reason to keep strange tomcats away from lactating
female cats. On the other hand, the tomcat which is familiar with the female, and has
sired the kittens, is not likely to kill the kittens. While this is what some breeders have
found, a good recommendation is to be watchful when a tomcat is around. Even without
any parental care by the male, the personality of kittens can often be related to the
personality of the tomcat (Turner et al., 1986; Reisner et al., 1994).
This is an aspect of reproductive behaviour that gets less attention in the literature than
maternal behaviour, probably reﬂecting fewer problems in this area. We will ﬁrst discuss
some major aspects of male and female sexual behaviour and then deal with problems.
In nature and in our neighbourhoods, much of the general activity of cats takes place
at night, including interactions with the opposite sex. A female cat in oestrus shows
a heightened activity level and her distinct mating calls often attract breeding males
from near and far. Sex attractants in her urine may provoke visiting male cats to stay
around and unfamiliar males to appear on the doorstep. In the presence of a male,
females that are in oestrus are likely to assume a receptive posture –elevation of the pelvic
region, deviation of the tail to one side, and treading of the back legs. As the male cat
investigates, these responses become more intense. The receptive posture is, at times, so
uninhibited that this behaviour can be displayed to the pet owner or induced by stroking
the female on her back and touching the perineal region. The response can be enhanced
by grasping the skin over the back of the neck while stroking the perineal region.
Whether in the back yard or the home den area, if a male is comfortable with the
surroundings, he will approach the female, and do a genital investigation. The investi-
gation often evokes a gape or ﬂehmen by the male. Flehmen presumably allows the
male to conﬁrm the markers of oestrus in genital secretions and urine. The male next
takes a neck grip on the female, mounts and usually engages in alternate stepping of
the back legs. (This neck grip usually immobilises the female, just as it does when a
mother cat moves her kittens while carrying them in her mouth.) Mounting is fairly far
forward on the female and he then slides backward while continuing the leg stepping
until he gains intromission. The simultaneous leg treading helps the process along.
Pelvic thrusting begins at the time of intromission and soon there is a deep pelvic
thrust, where the male remains motionless for a few seconds. At this time, emotional
activation seems to build up in the female, as indicated by her eyes dilating. Ejaculation
occurs after a few seconds and the female rather suddenly pulls away, typically emitting
a loud cry. She often turns as if to try to hit at the male, as he springs back. She then
begins the feline signature, copulatory after-reaction, licking her genitalia and rolling
and rubbing on the ﬂoor. The male engages in his own bit of genital licking. The genital
licking behaviour is more than just surface hygiene as the male is physically cleansing
33Normal and problematic reproductive behaviour in the domestic cat
the penis and then applying antibacterial saliva. Cats seem to be afﬂicted with few
sexually transmitted diseases, one of the reasons being that the transmission of genital
diseases is broken by the genital licking (Hart, 1990, 2011).
When a female cat is mated, whether she becomes pregnant or not, her oestrus
lasts for 4–6 days, and she does not come back into oestrus for that season. However,
if she is not mated, the oestrous period may last for as long as 10 days and she recycles
at intervals of 2 or 3 weeks. This pattern reﬂects the fact that ovulation in the female
domestic cat is induced by copulation –so-called reﬂex ovulation. Once mated, the
female does not have to put up with any more courtship attempts or matings.
Cat breeders often understand this system of reﬂex ovulation and when they desire
not to have a female bred, or not to have the female repeatedly come into oestrus, they
can evoke ovulation by probing the vagina with a smooth blunt instrument such as a
glass rod. Several insertions of 10 s, about 5 min apart, for a couple days are usually
sufﬁcient to induce ovulation (Diakow, 1971). Females may even display the copulatory
after-reactions to these insertions.
In the wild, i.e. among cats with outdoor access or living in outdoor colonies, only a
few studies of the mating system of domestic cats have been conducted and these
were summarised by Liberg et al. (2000) in the second edition of this book. Most of
those studies concerned group-living populations. At lower cat densities in rural areas,
a dominant ‘breeder-class’male’s range covered the home ranges of several females,
but the ranges of breeder-class males overlapped even during the mating season.
(The socio-spatial organisation of domestic cats with outdoor access is related to food
abundance and dispersion –see Chapter 5.) In this study, females in oestrus were often
courted by more than one male, especially at higher cat densities such as that reported
from a central Roman colony, where up to 20 males were seen to court the same oestrous
female (16 simultaneously). Nevertheless, the authors concluded that male cats compete
for females singularly and mating success is strongly correlated with dominance, which
in turn is correlated with age and body weight. The authors also concluded that more
ﬁeld research is needed to determine if female cats actually ‘choose’their mates in such
systems and mention several hypotheses on how this might occur.
Problems with males
In the home or breeding facility setting, failure of a male to show interest in females
or their discomfort with the breeding environment may be reﬂected in an absence
of mating. Sometimes even a highly motivated male may fail to copulate because of
physical interference with intromission.
The ﬁrst of these problems, an apparent lack of sexual prowess, can be addressed
by giving the male sufﬁcient time to acclimate to the breeding area even before the
receptive female is placed with him. The pair should be allowed to mate several times
in succession. For regular breeders, if a speciﬁc area is reserved for breeding, the male,
who is usually the one that needs acclimation to the room, may come to anticipate
copulation when placed in that area. The most wary male may wait a few hours before
copulating, but after a series of matings, he will usually copulate within 15 min or so.
34 From Kitten- to Adulthood
One problem seen in long-haired cats is that a hair ring may develop around the
base of the penis, actually preventing intromission (Hart & Peterson, 1970). The hairs
may come from the preputial sheath of the male, or with frequent mating, from the fur
of the female when the penis is rubbed over the back of the female. While the hair ring
is often removed by the males themselves, the owner can also remove the ring
by gently sliding it over the penis. Males are usually able to mate immediately after
removal of the hair ring.
The problem of lack of interest by a male could be due to low levels of testosterone.
The blood testosterone levels can be analysed, compared to a normal range, providing
several blood samples have been taken throughout the day, as blood testosterone
concentrations ﬂuctuate. Normal copulatory activity can occur with half of the usual
level of testosterone, so testosterone levels would have to be quite depressed to account
for a male’s lack of sexual interest.
The occurrence of a painful or fear-eliciting event during the mating encounter may
result in a male showing no interest in mating. In this case, the event that caused the male
to be fearful should be removed or the breeding moved to another area. If a general high
level of anxiety seems to be the cause, this behaviour could be passed onto the progeny.
Problems with females
These problems are primarily difﬁculties with oestrus detection and the rejection of
a male’s sexual advances even though the female shows signs of sexual receptivity.
As described above, the signs associated with sexual receptivity can be evoked by
petting on the back or even rubbing the perineal region while holding onto the skin over
the back of the neck –more or less as a male cat would do. However, these responses
cannot be elicited in all females at the time of oestrus. Placing the female near a sexually
active male may be necessary, even if not the intended sire.
A female that is in oestrus but will not accept the male is another, but not uncommon,
problem. By gently restraining the female, some males that are experienced might be
accepted. A male and female can be left overnight or at least for several hours, hoping
for the best. The drawback here is that you cannot know whether mating has occurred.
If the female has not been induced to ovulate she will be in oestrus again a week or
more later. One particular male might be accepted by a female but not others. A simple
solution would be to present the female a different stud male. One other thing that can
interrupt breeding harmony is the occurrence of a painful and fear-eliciting event, just
as with males. Removing the objects causing the reactions or moving the breeding
area could be attempted.
Reproduction in cats has several aspects unique to domestic animals. For one thing,
reproductive behaviour in both sexes is fraught with individual idiosyncrasies and
special sensitivities, especially in the home or breeding cattery. Fortunately, cat breeders
35Normal and problematic reproductive behaviour in the domestic cat
seem to understand that the management of this aspect of a cat’s life in a human
environment is a place where persistence and patience are invaluable.
Financial support for preparation of this chapter was provided by grant (#2009–36-F)
from the Center for Companion Animal Health, School of Veterinary Medicine, at the
University of California, Davis.
36 From Kitten- to Adulthood