Lesson on the world around us. 2nd grade. Topic “Cat in our house” lesson plan on the world around us (2nd grade) on the topic

Pregnancy (Graviditas) is the physiological state of a cat from the moment of fertilization until the birth of mature fetuses, and in the case of one or another pathology, until abortion.

Pregnancy in a cat can be primary or repeated.

According to the flow there are:

• Physiological pregnancy with the normal state of the cat’s body and fetuses.
• Pathological pregnancy, in which pregnancy occurs with disruption of physiological processes in the body of a cat or developing fetus.

A cat's pregnancy is preceded by a number of physiological conditions that lead to the development of pregnancy.

Species feature of the reproductive cycle in a cat

Cats are polycyclic animals with a sexual season and reflex (induced by sexual intercourse) ovulation. A cat allows sexual intercourse only in the stage of arousal. The sexual season in our conditions for cats lasts from the end of January until September, sometimes until November. At the same time, the timing of the sexual cycle and the duration of sexual cycles in cats depend on the breed, environmental conditions, individual characteristics, communication with relatives and other factors. In cats living in city apartments, under the influence of artificial lighting, sexual cycles can be repeated almost throughout the year, especially in short-haired breeds (Siamese).

The duration of individual stages of the sexual cycle, except for the balancing stage, depends entirely on ovulation. The anovulatory sexual cycle lasts 2-3 weeks, the ovulatory cycle lasts 6 weeks (30-75 days).

After giving birth in lactating cats, the first sexual cycle can occur on the 7-10th day, in some cats on the 2nd day of lactation. However, in most cats, sexual cycles resume 7-8 days after the kittens are weaned or at 4-6 weeks of age. If the owners of the animal wean the kittens in the first 24 hours after birth, the cat may come into heat in 2-3 weeks.

Preoestrus in a cat precedes the onset of heat and lasts 1-3 days with little pronounced signs of estrus. Unlike dogs, cats do not experience bleeding; we notice frequent urination. The cat strives to be picked up and caressed.

The stage of excitement with the phenomena of estrus and heat is pronounced; in some cats it is accompanied by such strong excitement that the owners involuntarily suspect that their cats have rabies. The cat refuses food, emits piercing screams - wild meows, arches its back, rolls on the floor, rubs its head and neck on the floor, the ground, moves its tail to the side, strives for the cat and allows it to sit. The arousal stage lasts an average of 7-10 days in a cat (5-14 days in the spring and 1-6 days in other periods of the year). If mating has occurred, the duration of the cat's arousal stage is reduced to 4-6 days. Subsequently, within 24-48 hours after ovulation, sexual arousal fades away.

Ovulation in a cat occurs 22-50 hours after intercourse: irritation of the nerve endings of the vagina and cervix during coitus causes the release of releasing factors from the hypothalamus, which stimulate the release of LH (luteotropic hormone) from the pituitary gland, under the influence of which ovulation occurs. In some cats, ovulation occurs after a single mating, in others only after several coitus with a cat.

The subsequent stage of inhibition is characterized by a weakening of sexual arousal and the cessation of the cat’s attraction to the cat. In cats that have not had coitus with a cat (non-ovulated), this stage lasts 2-4 weeks (an average of 21 days). If there was mating, but fertilization did not occur, then the corpus luteum of the ovaries secretes progesterone (corpus luteum hormone) for 30-40 days; in some cats, the hormone progesterone causes the development of false pregnancy, which in a cat lasts 30-45 days, sometimes up to 70 days. Moreover, after a false pregnancy, the cat’s next sexual cycle occurs after 7-8 days.

Dog reproductive cycle

The timing of puberty in dogs varies significantly depending on the breed. The first heat in small breed dogs usually occurs at the age of 6-10 months, and in large breed bitches the first heat can be delayed up to 24 months. In this regard, the absence of estrus before 2 years of age is not considered a sign of pathology.

The reproductive cycle in female dogs is divided into 4 stages: proestrus, estrus, diestrus and anestrus.

Proestrus is manifested by swelling of the vulva (outer labia) and bloody discharge from the vagina. During this period, the bitch flirts with the male, but does not allow mating. Sometimes this period goes unnoticed due to the fact that the bitch intensively licks vaginal discharge. The duration of this period ranges from 2 to 25 days (average 9 days).

During estrus, the bitch allows mating. During this phase, ovulation and fertilization of eggs occurs. The duration of the period when the bitch allows mating also varies widely from 2 to 20 days, but on average it is 5-9 days.

Diestrus begins after ovulation and is associated with the activity of the ovarian corpus luteum. The duration of this period depends on whether the bitch is pregnant or not. In puppyed bitches, the duration of diestrus is 56-58 days, and in non-puppy bitches it is 60-100 days.

Anestrus is the resting phase when the development of follicles in the ovaries stops. The duration of this period is approximately 4 months.

The sexual cycle in dogs repeats 2 times a year (on average every 7 months). Some dog breeds only go into heat once a year. Due to individual characteristics, it is recommended to carry out mating only after the second heat. This will enable the owner of the bitch to track how the estrus progresses, what period of time each period takes. In addition, the first estrus may be incomplete, not accompanied by ovulation, and the animal’s body itself may not yet be ready for pregnancy.

Despite the external manifestations of the reproductive cycle, sometimes even experienced owners find it difficult to understand when a female dog is ready for fertilization. In this case, several methods are used to diagnose the fertile period.

To determine the stage of estrus, a smear is taken from the vagina, stained, and the type of vaginal epithelial cells, the presence of bacteria and blood cells are assessed. This is a good research method that allows you to fairly accurately judge the current phase of the sexual cycle. It is often necessary to take several swabs several days apart for greater accuracy. A more modern and accurate method is to determine the level of hormones in the blood (for example, progesterone).

If the mating turns out to be fruitful, then pregnancy develops. The larger the bitch, the larger the litter size, as a rule. Toy breeds give birth to 1 to 4 puppies, while large females can produce up to 15 puppies. The first pregnancy is usually low-fertility. Also, the number of fruits decreases as the animal ages.

Sexual intercourse

Sexual intercourse (copulation, coitus) is the coordinated reflex actions of a male and female (cat and cat), accompanied by the introduction of the male's sperm into the genital tract of the female (cat).

Sexual intercourse consists of the following reflexes: approach, erection, hugging, copulation and ejaculation.

The approach reflex, or sexual desire, is the desire of a female in heat and a male to find each other in the environment and get closer. Attractive stimuli include smells, sounds made by animals, as well as its appearance and behavior.

The erection reflex is the filling of the penis with blood, which becomes elastic and ready for sexual intercourse. In females, the erection reflex is manifested by hyperemia of the mucous membranes of the genital tract and filling of the cavernous bodies of the clitoris with blood.

The hugging reflex - in the male is accompanied by jumping on the female and clasping her with his thoracic limbs, and in females - by not resisting sexual intercourse.

The copulatory reflex in the male manifests itself in the form of pushing movements of the pelvis, and in the female by adopting a position that facilitates the insertion of the penis into the vagina to its full depth.

The ejaculation reflex is the release of sperm from the male genitals. The amount of sperm released in one session is called ejaculate. In females, the ejaculation reflex involves the secretion of the vestibular and uterine glands.

In cats, preparation for sexual intercourse takes 1-5 minutes. The cat grabs the cat's neck with its teeth and presses it down. In this case, the cat’s hind limbs are widely spread apart, the penis is inserted into the vagina from above at an angle of 20-30 degrees to the horizontal plane. The horny denticles on the head of the cat's penis cause pain to the cat. During sexual intercourse, a cat makes a peculiar squeak, and a cat makes grumbling sounds. The duration of coitus is 5-10 seconds.

Mating can be manual and free. Cats are usually mated 2-3 days from the beginning of the arousal stage of the sexual cycle. After a single coitus, some females remain unfertilized - this happens when the follicles in the ovaries have not yet reached the required maturity. Considering this fact, it is recommended to carry out two or three coitus with an interval of 12-24 hours.

About Pets - educational site about pets

Sexual maturity is the ability of animals to produce offspring.

Puberty occurs at 6–8 months. The timing of puberty depends on many factors, primarily on the breed, sex, climate, feeding, conditions of keeping and care. Females become sexually mature somewhat earlier than males.

Puberty occurs much earlier than the end of growth and development of the entire organism. But the appearance of the first heat does not mean that the cat is ready to reproduce - the pelvis is not yet ready for childbirth, the mammary glands are underdeveloped. The cat is a polycyclic animal with a sexual season and reflex ovulation. Sexual season is the time of year when animals exhibit intense sexual cycles. The reproductive cycle is the totality of all physiological changes occurring in the female reproductive system from one ovulation to the next.

The sexual cycle without fertilization consists of the following periods: proestrum, estrus, metoestrum, aestrum. The timing of the sexual season and the duration of sexual cycles in cats varies greatly depending on the breed, individual characteristics, environmental conditions and housing.

Proestrum in cats precedes the onset of heat and lasts 1–3 days. Cats become restless as they prepare to go into heat. They rub against objects or the legs of their owner, and walk slowly with their knees bent. Estrus, or sexual heat, is manifested by the fact that the cat strives for the male and allows him to mate. This phase lasts 7–10 days. Estrus occurs - mucus is released from the genitals. During this period, ovulation occurs in the body of cats, namely 22–50 hours after sexual intercourse (coitus, or copulation). In some cats, ovulation occurs after a single mating, in others - after several coitus. Ovulation is the opening of mature follicles and the release of oocytes, which after a few hours descend through the fallopian tubes and turn into a mature egg. If during this period the cat is not fertilized by the cat, the eggs will not be released, the swollen mucous membrane will gradually return to normal and will prepare for the next heat. In the absence of fertilization after ovulation, an inhibition stage occurs - metoestrum, then a resting stage - anestrum.

The onset of a period of sexual arousal is judged by changes in the cats' behavior. The cat forces the male to “beg” itself for a long time and runs away from him. Therefore, as a rule, the cat is carried to the cat so that he feels confident in his territory and patiently waits for the cat to stand up with the back of the body slightly raised and the tail bent to the side. The cat grabs her by the fur on the back of her neck with his teeth and begins to cover her. Copulation between a cat and a cat occurs within about 5 seconds. At the end of copulation, the cat emits a piercing cry and the male quickly jumps to the side, and the cat turns over on its back and begins to roll.

A cat is capable of covering a cat 10 times in an hour. For successful fertilization, it is necessary to keep the cat and the cat for 2-3 days. If several male cats bred the same female, multiple fertilizations may occur and each kitten in the litter may have a different father.

Females can only mate during estrus, while males are ready to mate cats at any time, although the most active period associated with sperm concentration is early spring, with the next peak occurring in the summer months.

The intervals between estrus vary, and this depends on the breed of the animal, but most importantly, on the time of year. Common domestic and pedigree cats that live in and are dependent on a person's home may have many more heat cycles, spaced about 15 to 25 days apart, although each female may have her own individual characteristics.

In well-fed animals, estrus periods may be extended. It should be noted that in overfed or weakened animals, estrus may occur with invisible or muted signs. On average, sexual hunting stops in cats at 10 years of age. However, there are exceptions.

In the event of fertilization, nutrients accumulate in the female’s body. The pregnancy period begins, which lasts 55–63 days (60 days on average) and ends with lambing (birth). The cat gives birth to 4–6 blind, deaf and toothless kittens weighing approximately 60–70 g.

On average, a cat produces 2–4 litters per year. In total, an animal can give birth to about 100 kittens during its life.

Fertilization of the egg occurs in the upper third of the oviduct. The lifespan of sperm in the genital tract ranges from 3 to 4 days. The ability of eggs to fertilize remains up to 18 hours.

From the moment of fertilization, the fertilized egg is called a zygote, which divides asynchronously and turns into a germinal vesicle. Then the germinal vesicle is implanted into the mucous membrane of the uterus. Due to the development of fertilized eggs, an increase in the corpus luteum occurs, formed at the site of ruptured ovarian follicles. The corpus luteum secretes progesterone into the blood, which inhibits the development of new egg follicles and promotes the penetration of choroidal villi into the uterine mucosa. This creates conditions for the development of the embryo.

After the embryonic period comes the pre-fetal period of development. During this period, the laying of all organs and the skeleton occurs, and the placenta (afterbirth, or child's place) is formed. From this time on, such an organism is called a fetus, it develops fur and sweat glands, a central nervous system, and striated muscles and genitals appear.

Soon after fertilization, a pregnant female's metabolism changes and a good appetite appears. The energy requirement increases 4 times. The coat becomes smooth and shiny, the body shape takes on a rounded shape. In the second half of pregnancy, despite the remaining appetite, the animal loses weight because it does not have time to assimilate a sufficient amount of nutrients.

In very rare cases, cats experience false pregnancy. It is accompanied by all the signs of a normal pregnancy, but the embryo does not develop. Cats with false pregnancies get fatter, gain weight, prepare their nest, and sometimes even produce milk. The causes of false pregnancy are purely physiological and are not some kind of pathology. This state continues for several days. During this period, it is necessary to reduce the diet, reduce the amount of water, and increase walks. The veterinarian may prescribe estrogens and androgens that suppress lactation.

Sometimes cats have miscarriages. They are usually the result of rough handling of the animal or the presence of a uterine infection.

Childbirth is a physiological process in which a mature fetus, its membranes and the fetal fluid contained in them are expelled from the uterine cavity. During the birth process, a mature fetus transitions from intrauterine life to independent life. The onset of labor is heralded by swelling of the vulva, the appearance of mucous discharge from the cervical canal and a decrease in body temperature by 1 °C. Childbirth begins with the opening of the cervical canal, which lasts 3–6 hours. In this case, the fetal bladder of the first kitten is visible from the lumen of the canal. The female shows anxiety, breathes heavily, makes a den for herself in a secluded place and lies down from time to time. As soon as the first kitten is pushed into the canal of the mother's cervix, the abdominal muscles reflexively come into play and labor enters the fetal expulsion phase. The duration of labor is from 45 minutes to 5 hours. They are accompanied by contractions of the muscles (they are called contractions) and the abdominal muscles (these movements are called pushing). Contractions last 2–5 minutes with pauses of 5–10 seconds.

The cervical canal opens due to the introduction of fetal membranes into it in the form of amniotic fluid. As it passes through the vagina, the embryonic sac often bursts and the hind limbs of the fetus appear. When the membranes rupture, colorless, slightly opalescent waters leak out, and when the placenta is disrupted, greenish water flows out, and bleeding begins from the erosion formed in the wall of the uterus. After the next kitten is born, the female licks it and bites through the amnion with her incisors, that is, she removes the fetal membrane first from the head and then from the body. When the kitten is freed from the membranes, the female independently gnaws the umbilical cord and eats the remaining placenta, which she needs because of the numerous stimulating hormones it contains for subsequent labor. The placenta is released simultaneously with the fetus or within 15–30 minutes after the birth of the kittens.

The postpartum period continues until the completion of involution of the genitals and other organs that changed during pregnancy and childbirth. In cats, the choroid of the uterus has a close connection with the mucous membrane, due to which, when the placenta is separated, the mucous membrane is partially detached, accompanied by minor bleeding that quickly passes as the uterus contracts. In the first 2–4 days after birth, the remaining epithelium of the uterine mucosa is rejected. The discharge on the 3rd–5th day becomes brown with a greenish tint, then it gradually becomes lighter, and on the 9th–14th day the lochia is transparent and viscous.

The cervix closes after the uterine cavity is cleansed. Involution and regeneration of its mucosa are completed by the 4th–5th week.

Fertilization of a cat

Fertilization is the process of fusion of a sperm and an egg, resulting in the formation of a new cell - a zygote. Fertilization of the egg occurs in the upper third of the oviduct, where the egg meets the sperm.

During ovulation, the egg, together with the follicular fluid, enters the funnel of the oviduct and, thanks to contractions of its walls and vibrations of the ciliated epithelium, gradually moves along the oviduct into the uterine cavity. Sperm, introduced into the cat’s genital tract during sexual intercourse, moves towards her. When sperm meet an egg, they surround it and penetrate into the area of ​​the corona radiata. Sperm secrete the enzyme hyaluronidase, which dissolves the intercellular substance connecting the follicular cells of the corona radiata. As a result, the transparent membrane is exposed, into which the sperm are embedded. In this case, one of them penetrates into the protoplasm of the egg, where the tail of the sperm dissolves and the head quickly swells, reaching the size of the nucleus of the egg. After this, the nuclei (pronuclei) of the male and female germ cells merge and a new cell is formed - a zygote, from which a new organism is formed.

Cats have a vaginal type of insemination.

Sperm capacitation . Sperm become capable of fertilization only after a certain period of stay in the genital tract, where they undergo certain changes called capacitation. Its essence boils down to the release from the acrosomal head of the sperm of the enzymes necessary for its penetration through the transparent membrane of the egg. For a cat, this process takes 2-24 hours. The survival of sperm in the genital tract of cats lasts up to 2 days. The fertilizing ability of an egg after ovulation in a cat lasts 24-26 hours.

Estrus (estrus)

External signs of the onset of estrus are manifestations of hypersexuality. The cat, at the same time, emits piercing screams, moves its tail to the side, raises its butt, periodically squats, wriggles in waves, trembles with excitement and rolls on its back. This is the peak phase of estrus and during this period all cat actions are aimed at attracting a male. If the cat’s sexual needs remain unfulfilled, then estrus turns into real torment for her.

Heat indicates that the cat is ready to mate.

The transition to estrus indicates that the cat is ready to mate. This cycle begins on the first day of “letting go.” The hunt lasts from four to six days.

In cats, estrus occurs without any bleeding, limited only to preparation for ovulation (the release of eggs from their ovaries into the body cavity).

During estrus, a cat shows its readiness to mate with its entire appearance.

Spontaneous ovulation in cats, as well as in representatives of the canine family, does not occur, since it is of a reflex nature, in other words, it occurs only as a result of repeated matings.

The rough head of the male's penis irritates the female's vagina during mating, which stimulates the production of another pituitary hormone, namely luteinizing hormone. Increased secretion of this hormone leads to the development of a corpus luteum (temporary endocrine gland) in place of the follicle. It is the corpus luteum that produces the hormone that protects pregnancy - progesterone.

The time of ovulation varies from about a day to thirty hours. If during estrus there was no coverage by the cat, then after about a week or two the sexual cycle resumes, that is, first there is a pre-estrus, and then there is estrus again.

It is thanks to progesterone that the uterus is prepared to receive fertilized eggs and feed embryos with royal milk before implantation (fixation) to the uterine wall occurs. Embryos are implanted approximately two weeks after mating.

During the sexual cycle, the cat urgently needs vitamin E

If a cat has a weak estrus, then vitamin “E” should be included in its diet, which, among other things, promotes the formation of eggs and their attachment to the uterine walls. In addition, to stimulate estrus, some breeders place a weakly estrus animal with a cat in estrus. Others place her next to the cat in order to stimulate the corresponding processes, or they place a sponge or rag in the house that has previously been soaked in the urine of an adult cat (preferably a March one). This method has also proven itself quite well: increasing natural light every day to fourteen hours.

Pregnancy

After fertilization of the cat’s egg, pregnancy develops, during which the cat notices:

Development of the embryo and membranes. The zygote, moving along the oviduct into the uterine cavity, quickly fragments. At the beginning, two blastomeres are formed, then four, eight, etc. A cluster of blastomeres without a separate cavity is called a morula. The zygote in the morula stage enters the cat’s uterus 5-8 days after fertilization. A germinal nodule is formed - an embryoblast, and the outer layer of its cells is the trophoblast (feeding leaf). A fluid and a cavity appear between them, and the morula turns into a germinal vesicle - a blastocyte.

Attachment of the embryo to the uterine mucosa—nidation—occurs in cats from days 12-13 to 17. Subsequently, the fetal body is formed from the embryoblast, and the aqueous membrane and placenta are formed from the trophoblast (these are temporary organs of the fetus). In cats, 3 weeks after fertilization, the embryo is surrounded by fully developed membranes: aqueous, urinary and vascular.

Changes in the mother's body during pregnancy . As many corpora lutea develop in the ovaries as the number of egg follicles have matured and ovulated. The uterus begins to develop rapidly, muscle fibers lengthen by 7-12 times and thicken by 3-5 times. Arteries and veins expand 4-5 times and lengthen, new vascular branches appear. A plug of thickened mucus forms in the cervix, preventing infection from entering the vagina. The walls of the uterus form around each fetus expanded areas (ampoules) of a rounded shape, then as the fetuses grow, they acquire an oval shape, and by the end of pregnancy the border between them gradually smoothes out.

With a small number of fetuses, the horns of the uterus form a loop in the abdominal cavity that reaches the diaphragm and liver. If there are a lot of fetuses, a second loop of uterine horns may appear, convexly facing the pelvis. Thus, the uterus can form up to six layers lying in rows.

Cat breeding

The age of sexual maturity in cats depends on a number of factors: the sex of the animal, its breed, living conditions, quality of food, etc. It is during puberty that they become able to produce mature eggs and sperm.

Cats reach sexual maturity at 7-9 months, and in some breeds earlier. But it is recommended to carry out the first mating no earlier than a year (for both males and females). Cats in heat are accompanied by manifestations of varying intensity; if estrus ends with fertilization, then all its signs disappear within 12 hours, and sometimes after a longer time.

Cats can be in heat throughout the year. It was believed that they occur only 2-3 times a year, mainly in spring and autumn. But in purebred domestic animals they can occur at intervals of 15-25 days (see table); their duration is 6-8 days, but there are always exceptions to the rules.

In cats, the reproductive cycle is much simpler than in females. The cycle of heat and preparation for it may be disrupted. They disappear during pregnancy, become less common or fade away at an older age (at about the 8th year of life).

Breastfeeding does not interfere with the onset of another heat, so the nursing cat can again be impregnated by the male. The number of kittens in one litter ranges from one to six, in some cases there may be more. As a rule, this depends on the physical fitness of the cat - for example, a young cat that has not yet given birth produces fewer kittens than an older cat.

The number of offspring is not related to the timing of fertilization of the female. If the timing of mating is chosen incorrectly, the cat may reject the male or fertilization will not occur. Even the number of matings between a cat and a cat does not affect the number of future young animals.

If a cat mated with a cat, this does not mean that she became pregnant. The first signs of pregnancy can be noticed no earlier than three weeks later. The cat becomes voracious, the nipples swell and turn pink; embryonic movement appears in the 6th week of pregnancy.

The gestation period usually lasts 63-66 days, but sometimes 56-71 days. Siamese cats have a shorter pregnancy than other breeds.

Until approximately the 60th day of pregnancy, the cat behaves normally. But 3-4 days before the onset of birth, her behavior changes: the cat becomes restless, follows on the heels of the owner; body temperature drops to 37°.

In rare cases, animals experience a false pregnancy, when, despite all the signs of a normal pregnancy, the embryo does not develop. There are also miscarriages. The reason for this may be weakness of the fetus, rough handling of the animal, or a uterine infection.

If the cat's owner is not interested in the offspring, then castration or sterilization can be resorted to. As a result of these operations, animals lose their sexual attractiveness to individuals of the opposite sex.

On the eve of the birth, the cat owner should stock up on the necessary items that may be needed: scissors with blunt ends, thread, pieces of flannel and gauze. Everything must be sterilized. The fur, if it is long, needs to be cut around the nipples and genital opening.

The box or box for the “nest” needs to be disinfected, then lined with an old blanket and several layers of paper on top (now it is possible to use baby diapers).

Often the cat chooses its own place, so you should be more careful about this.

Before giving birth, the cat begins to get nervous, after which labor pains begin (an hour before the birth of the first kitten). If the cat cannot give birth to the first kitten within 7-8 hours after the water breaks and the onset of contractions, it is necessary to seek the help of a veterinarian. As a rule, a cat copes with childbirth on its own, but sometimes it still needs human help. The intervals between the appearance of kittens range from 10 minutes to several hours. At this time, the cat should be given a drink (blackberry tea or milk), caressed and encouraged.

The kitten is born within 1-2 minutes, after which the mother gnaws the umbilical cord and licks the baby. Sometimes a kitten is born directly in the fetal sac; he should not be in it, because he may suffocate. The sex of newborn kittens is determined by the appearance of the external genitalia and their location in relation to the anus. Males have a scrotum with a penis removed from the anus, and females have a small vulva almost next to the anus.

Cat offspring need mother's milk, which is the basis of their nutrition. The mother's mammary glands begin to function immediately when the baby first sucks. Newborn kittens of both sexes of all breeds weigh from 80 to 120 grams. In the first week they double their weight, and every week - up to 100 g on average.

Kittens usually switch to normal food from mother's milk at 3-4 weeks of life. Even if the cat has a lot of milk, you need to feed the kittens no later than a month later - first with warm milk (preferably dissolved dry milk), and then with solid food. You should start feeding with boiled and raw meat, then porridge from boiled chicken and fish with rice water, lean beef and veal, cottage cheese and entrails (liver, kidneys).

Already at 4 months of age, kittens should be switched to an adult diet.

How long does a cat's pregnancy last?

A cat's pregnancy lasts on average 63-65 days . Depending on the breed, pregnancy can last from 56 to 70 days .

What affects the length of pregnancy in a cat?

• Number of kittens. The more kittens a cat has in her uterus, the faster she will go into labor.
• Weather. Air temperature and atmospheric pressure have an impact on the timing and course of pregnancy. As a result of a sharp change in ambient temperature or pressure changes, a cat's labor may begin prematurely.
• The length of the coat affects the duration of pregnancy. Short-haired cats carry their fetuses in the womb for less time than long-haired cats.

How many kittens can a cat give birth to?

If we consider averages, then an ordinary cat can give birth to 6-8 babies at a time. However, the number of cubs is not just the will of fate, but a confluence of many factors. There is a case in history when a representative of the Persian breed gave birth to 15 kittens at once. It is also not uncommon for 1-2 babies to be born. So, what will determine the number of future babies?

Features of the female body

How many kittens a cat gives birth to depends, first of all, on the characteristics of her body. The first birth is usually a surprise, and then the owners know roughly what to expect from their pet. What will affect the female's fertility:

1. Age

   : Primiparas and late-parous women are unlikely to have many babies. Most likely there will be about 1-2 cubs.

2. Genetics

   : if the cat’s mother was fertile, then the daughter will most likely inherit this quality.

3. Size

   : a miniature cat, even in its prime, will not bring too many kittens, but a large and well-fed female is capable of regularly giving birth to a large number of babies.

4. Health

   : if the cat has any problems, then she will bring significantly fewer kittens.

If you know the cat’s mother and this is not the first time you have observed childbirth, then it will not be difficult to determine the approximate number of fetuses even without an ultrasound.

Male fertility

The number of offspring is influenced by the characteristics of your cat's partner. For example, his age: if the cat has not reached 1.5-2 years of age or, conversely, is too old, the quality of his semen will be an order of magnitude lower than that of strong and healthy cats. Pay attention to the frequency of matings of the cat - you should not expect a large litter if he fertilizes more than 4 cats per year.

The father's health is undoubtedly one of the most important factors. Infectious diseases or diseases associated with the reproductive system can affect not only the number and condition of the offspring, but also the health of the mother herself. If you have a purebred cat and are looking for a mating partner, be sure to ask for a health certificate, the necessary documents on purebred, and also ask the owners how many kittens are usually born from a given male.

An amazing feature is characteristic of cats - in one litter there can be fruits from completely different fathers. This is due to the fact that eggs in the body are produced directly during mating. Therefore, outdoor cats produce more kittens than planned breeding pets.

Dependence on breed

Without a doubt, the fertility of a furry mother is also influenced by her breed. Surely you have noticed that ordinary street cats often give birth more than indoor cats? This is due to a simple truth - harsh conditions await children on the street, and the chances of survival are much less than at home. Therefore, to continue the race, a larger number of kittens is needed.

Purebred pets are not so fertile. For example, Scottish women give birth to an average of two or three babies at a time, but British representatives are already capable of bearing 4-5 babies. However, not everyone can master even this breed maximum.

Signs of pregnancy in a cat

Despite the fact that sexual maturity in cats occurs at 7-9 months, mating early is not recommended due to the fact that the offspring may be born weak or the cat’s body cannot cope with such a load on the body. Only after your cat is one year old can she be taken to mating. 2-3 weeks after mating, the cat may show the first signs of pregnancy - the cat’s nipples turn pink and swell. During the first month of pregnancy, a cat's activity decreases significantly; due to hormonal changes and changes in metabolism in the body, the cat may vomit in the morning. After 2-3 weeks, everything gradually returns to normal and the cat begins to eat more. By 4-5 weeks after mating, owners begin to notice weight gain in the cat; the cat’s weight, depending on the number of fetuses gestated, can increase by 1-2 kg. There is an increase in the volume of the abdomen, which by the end of pregnancy becomes pear-shaped. A cat's taste preferences may change, and its mood often changes. As the cat's belly grows, it begins to walk more slowly. At 7-8 weeks, the cat begins to look for a “nest”; we note anxiety and sometimes nervousness in the cat. If you place your hand lightly on the stomach, you can detect the active movement of the kittens.

• INTRODUCTION
• MATING
• SEMEN COLLECTION AND ANALYSIS
• Sperm storage and artificial insemination
• Artificial insemination methods
• LITERATURE

CHAPTER 10

Mating and artificial insemination in cats

E. Axner

INTRODUCTION

For breeding, animals are selected that meet breed standards, are free from defects and have a good temperament. Cats must have a history of uncomplicated births and have strong maternal instincts. The goal of breeding is to produce healthy kittens, not a few show kittens selected from a litter that has congenital defects or deviations from breed standards. Inbreeding can, over a certain period of time, contribute to the birth of kittens with excellent conformation, but in the future it can cause birth defects and is not recommended, especially when breeding rare, small breeds.

In order to differentiate reproductive problems caused by errors in maintenance from pathologies of the reproductive tract, it is necessary to understand the essence of the physiological processes that ensure reproductive behavior and the mechanism of ovulation. Infectious diseases often cause reproductive problems, so serious efforts are required from the breeder to prevent their spread. Before mating, both partners are examined, identifying signs of diseases, as well as possible hereditary defects. Destroy external and internal parasites. Testing for feline leukemia and feline immunodeficiency viruses is recommended. Breeding animals must be vaccinated against herpesvirus and calicivirus infections and panleukopenia. Conducting andrological and gynecological examinations before mating is not practiced, but it is recommended to examine the testes and penis of the male. If there is a history of reproductive dysfunction, the examination, including semen analysis, is carried out with greater care.

MATING
Behavioral estrus
Behavioral estrus in cats is explained by an increase in the concentration of estradiol produced by developing follicles.
Proestrus is short-lived (1–2 days) and is not always clearly expressed. The cat screams, rubs against various objects and owners, shows anxiety, but does not allow the male to approach her. After the onset of estrus, the screams become monotonous and persistent, the cat rubs its head, rolls on the floor, and takes a characteristic pose: it raises its croup and lowers its chest to the ground. At this stage, clear vaginal discharge is often observed. The characteristic behavior of the female (lordosis posture, stepping with her hind legs and moving her tail to the side) can be provoked by stroking the croup or grasping the animal by the withers (Fig. 10.1). Typically, your cat will experience decreased appetite and increased urination. However, in some cats there is little or no behavioral estrus despite elevated estradiol concentrations and follicular activity confirmed by blood or vaginal secretion testing. The intensity of behavioral estrus is related to the breed (oriental breeds have more pronounced estrus compared to Persian breeds). Fig.
10.1. Lordosis and rear paw walking can be induced by holding the cat by the withers and stroking the base of the tail or the perineal area
Fig.
10.2. The cat's post-coital reaction includes rolling on the floor and licking the genitals.
Behavior during mating
The cat attracts the male cat through calls, scent and characteristic behavior.
Before boarding, the cat squeezes the cat’s withers with its teeth and steps with its hind paws, often touching the cat’s perineal area, encouraging it to take a characteristic pose. Intromission lasts only a few seconds (from 3 to 30), with the sperm entering the vagina. At the end of mating, the cat emits a characteristic cry that rises to a piercing squeal. An experienced cat will hastily retreat to a safe distance, as the cat will attack him if he stays nearby. The so-called copulation cry and aggression towards the cat are part of the cat's post-coital reaction, which includes rolling on the floor and licking the genitals (Fig. 10.2). Often the cat will let the cat in for the next sitting within 10 minutes, although this interval can last up to an hour. The absence of a post-coital reaction indicates that intromission did not take place. Probably, this reaction of the female is explained by stimulation of the vagina by the spinous projections (spines) on the cat’s penis. Ovulation
Coitus stimulates the hypothalamus to produce GnRH, which in turn causes the pituitary gland to produce luteinizing hormone LH. Ovulation occurs when a certain concentration of LH is reached. The reproductive behavior of cats is characterized by repeated coitus, since single coitus does not provide a sufficient release of LH and ovulation. Most often, the necessary increase in LH concentration is observed after four matings.

The onset of estrus may not coincide with the ability to produce LH in response to coitus, so mating on the first or second day of estrus does not always cause ovulation, which is likely due to insufficient oocyte maturity.
After LH concentration increases to the required level, all mature oocytes ovulate simultaneously. This usually happens after 26–29 hours, counting from the mating, which occurred against the background of a high concentration of LH. Recent data suggests that spontaneous ovulation is much more common than generally believed (in 35% of cats out of 20 studied). Progesterone samples taken one week after mating can determine whether ovulation has occurred. A basal progesterone concentration indicates a lack of mating, insufficient intromissions, or a mating that occurred too early or too late. A progesterone level > 15 nmol/l (> 5 ng/ml) confirms the fact of ovulation. A long interestrus interval also indicates ovulation, although not all cats have a regular cycle. Organization of mating
According to generally accepted practice, mating is carried out in the environment familiar to the cat, therefore, as a rule, cats are delivered to the manufacturer.
If the cat is calm and experienced, and the cat is too timid, you can do the opposite. Animals should be given the opportunity to get used to each other and get comfortable in an unfamiliar place; Dim lighting helps create a feeling of security. If the cat is inexperienced, timid and does not allow the cat to approach, she can be brought to him by taking her by the withers and stroking the perineal area, thereby stimulating her to take a characteristic pose and encouraging the male to mount. To ensure ovulation, animals should not be separated until the third day of estrus and at least four coitus. Their completion is judged by the postcoital reaction of the female. An experienced and calm cat is chosen as a mate for an inexperienced cat, while mating with an experienced cat is preferable for an inexperienced cat. However, in some cases, adult females may reject a young, inexperienced male. Possible problems observed during mating are shown in Table 10.1. Table
10.1. Problems observed during mating and their solutions Problem:

An inexperienced cat rejects a cat.

Actions:

It is necessary to give the animals the opportunity to get used to each other.

Problem:

A cat in proestrus rejects a male cat.

Actions:

It is necessary to postpone mating until the estrus period.

Problem:

Reduced libido in a cat due to lack of experience (aggression on the part of the cat).

Actions:

You should mate with another, calmer cat.

Problem:

Lack of attraction to a specific partner.

Actions:

You need to change your partner.

Problem:

Preservation of the frenulum of the penis, preventing intromission.

Actions:

Perform surgical correction of the defect.

Problem:

Fur in the penis area prevents intromission.

Actions:

Remove fur.

Problem:

Dental problems that interfere with normal sitting.

Actions:

Inspect animals before breeding.

Problem:

Decreased libido caused by clinical diseases and/or testicular degeneration.

Actions:

Diagnose the disease and carry out treatment.

Problem:

Congenital defect - decreased libido.

Actions:

Exclude the animal from breeding, since such defects are often hereditary.

SEMEN COLLECTION AND ANALYSIS Semen
collection
Sperm is collected using an artificial vagina or electroejaculation.
In addition to the two mentioned methods, vaginal lavage after mating or sperm extraction from the tail of the epididymis after castration is practiced. Artificial vagina
An artificial vagina is made from a rubber “finger” from a Pasteur pipette and a small test tube (Fig. 10.3).
The male is allowed to mount the female in heat and an artificial vagina is brought in, with the male's penis pointed into it (Fig. 10.4). The disadvantages of this method include the need for the presence of an excited female, as well as the impossibility of carrying out the manipulation without prior preparation of the male, which takes 2–3 weeks. The procedure is successful only in 2/3 of cases. Sperm collection using an artificial vagina is effective in laboratory animals, but is rarely practiced in clinical settings. Fig.
10.3. An artificial vagina for collecting sperm consists of a rubber “finger” and a test tube
Fig.
10.4. Receiving sperm using an artificial vagina
Electroejaculation
The manipulation does not require preliminary preparation of the cat, but is carried out under general anesthesia so that the animal does not experience any discomfort.
A rectal probe (1 x 12 cm), made of non-toxic plastic and connected to an electrical stimulator (Fig. 10.5), is inserted into the rectum. The probe is equipped with three electrodes (1.5 mm x 5 cm), two of which (outer) are connected to each other, and the central one has the opposite polarity. To prevent rectal mucosa from getting between the probe and the electrodes, the latter must fit tightly to the probe body. The author's laboratory uses an electroejaculator operating at a frequency of 50 Hz, equipped with a transformer that provides continuous pulses of power from 0 to 30 volts. The device operates from a voltage source of 220 volts. Current and voltage are adjusted using a voltmeter and ammeter. Fig.
10.5. Equipment for electroejaculation in cats. Electrical stimulator and rectal probe with three electrodes

After anesthesia, the probe is lubricated and carefully inserted into the rectum 7–9 cm, directing the electrodes ventrally.
The penis is exposed by lightly pressing on its base and a laboratory test tube is brought to it. A series of 80 pulses with a power of 2 to 5 volts ensures ejaculation (Table 10.2). The general sequence of manipulations includes three series: 30 stimulations (10 each at 2, 3 and 4 volts), 30 stimulations (10 each at 3, 4 and 5 volts) and 20 stimulations (10 each at 4 and 5 volts). Between episodes there are pauses of 2–3 minutes. Stimulation begins by increasing the voltage for 1 second from 0 volts to the required voltage, after which it is maintained for 2–3 seconds at this voltage and sharply reduced to 0, again maintained for 2–3 seconds. There are other techniques that provide other voltages and duration of stimulation. Each discharge is accompanied by a reaction expressed in the stretching of the hind limbs, which indicates the adequacy of the stimulation. The absence of a reaction at a voltage of 2 volts or more indicates an incorrect position of the electrodes or the presence of feces in the rectum. During ejaculation, some of the sperm enters the bladder; this feature of the ejaculatory process is normal for domestic cats, but can be enhanced by the use of alpha-2 adrenergic stimulants (xylazine and medetomidine) for sedation. Table 10.2. Electroejaculation technique Vaginal lavage after mating
The method is not common in clinical practice, since only a few cats are capable of mating in an unfamiliar place, especially in a clinic.
Another disadvantage of the method is that the cat must be sedated, and that vaginal secretions and the liquid used for the procedure (saline solution heated to 37 °C) can affect the quality of sperm. The method is practiced when it is impossible to obtain sperm using an artificial vagina or electroejaculation. Collection of sperm from the epididymis
After castration, sperm is obtained from the cauda epididymis by washing the sperm from the epididymal duct or grinding the cauda epididymis.
The method is used when collecting sperm for scientific research or when it is necessary to preserve the sperm of a rare species of wild animals that died in captivity or as a result of an accident. Table
10.3. Assessing sperm quality All materials in contact with sperm must be heated to 37 °C to prevent cold shock

Color

White: high concentration.

Transparent: low concentration.

Yellow: Urine contamination, which has a destructive effect on sperm, is often observed when the voltage increases above 8 volts during electroejaculation.
Volume
Measured using a microtube.
Before further use, a small volume can be increased by adding a buffer or isotonic solution. Sperm morphology is assessed before mixing with the solution, as differences in osmotic pressure may increase the number of defective sperm. Motility
Sperm motility is assessed on a scale from 0 to 5. Its absence is considered zero motility; active forward movement is considered 5.
Concentration
is measured using a special camera (Bürker chamber) under a microscope.
The total number of spermatozoa is calculated taking into account the volume and concentration per unit volume. The percentage of spermatozoa with a head defect. A
stained sample (carbol fuchsin or nigrosin-eosin) is examined under a microscope with 1000x magnification.
The following are considered defective: a “pearl” shaped head; a head that has a narrowed base, irregularities in contour, an underdeveloped, separated or narrow head; as well as a head that has deviations in size. Other sperm defects
The sample is fixed in formalin and examined under a phase contrast microscope at 1000x magnification.
Sperm defects include proximal inclusions, distal inclusions, loss of the head, acrosome defects, acrosome changes, body changes, and duplication of tails. Spermatozoa linked by tails are also considered defective. In addition, the number of spermatozoa that do not have defects is counted. Presence of other cells in the ejaculate
The number of leukocytes, spermatogenic cells and degenerative epithelial cells (Papanicolaou) is counted in the stained sample.
Normal sperm quality
In cats, the volume of ejaculate is small (up to 0.01–0.77 ml). If sperm is collected using electroejaculation, then due to more intense stimulation of the accessory glands, its volume is noticeably greater than when obtained using an artificial vagina. The total number of sperm in the ejaculate ranges from 3 x 106 to 153 x 106, usually higher when sperm is collected using an artificial vagina than when it is collected using electroejaculation. Sperm motility varies and may be related to the duration of sexual abstinence. The osmolality of fresh sperm collected using an artificial vagina is about 320 mOsm/kg and increases during storage. Semen contains a lot of alkaline phosphatase, its pH ranges between 6.6 and 8.77. A content of normal sperm of 60% or more is considered normal; if the level is less than 40%, we can talk about teratozoospermia. However, the relationship between semen quality and fertility in domestic cats needs further study. Under natural conditions, normal fertility is observed even with less than 40% content of normal sperm in the ejaculate. If sperm is obtained by electroejaculation twice in a short period of time, the second sample will typically have greater motility and a higher percentage of healthy sperm. An experiment was conducted: sperm was taken from 15 cats of different breeds by electroejaculation 2 times during one anesthesia. It turned out that the number of healthy sperm in the first ejaculate is 40.9%, while in the second it increases to 54.6%, despite the fact that the first ejaculate has a higher concentration. From the above it follows that to determine fertility, it is advisable to conduct several sperm tests.

SPERM STORAGE AND ARTIFICIAL INSEMINATION
Sperm storage
Sperm is stored for 24–48 hours in a cooled buffer solution.
If long-term storage is expected, it is frozen. In most cases, determination of sperm parameters after storage is carried out in vitro, although there is little data on the successful insemination of cats with sperm subjected to long-term storage. Chilled diluted semen
Due to the fact that the quality of male semen is studied in vitro, the results of insemination are difficult to predict.
To store sperm at a temperature of 4–5 °C, Test-T buffer is used (Table 10.4), containing 20% ​​egg yolk and 5% glycerol. Storage leads to a decrease in sperm motility and the percentage of intact acrosomes. An increased content of yolk and sugars reduces sperm motility during storage, so a simple TesT buffer that does not contain sugars or yolk is quite suitable for diluting sperm. Table
10.4. TesT buffer N-tris-hydroxymethyl-methyl-2-aminomethane-sulfonic acid (Tes) - 11.2 g in 150 ml of distilled water;

Trishydroxymethylaminomethane (Tris) - 2.9 g in 75 ml of distilled water;

Penicillin B - 1000 IU/ml;

Streptomycin - 1 mg/ml.

*Tes is adjusted to pH 7.4 with This buffer.
Yolk and glycerin are added if the solution is intended to be used for freezing sperm (this is not necessary for cooling). Table
10.5. Buffer solution containing yolk and lactose Deionized water - 76 ml;

Lactose - 11 g;

Glycerin - 4 ml;

Streptomycin sulfate - 1000 mg/ml;

Penicillin G - 1000 IU/ml;

Egg yolk - 20 ml.
Freezing sperm
Cat sperm is frozen in yolk-lactose buffer (Table 10.5).
Freezing in pellets and payettes gives comparable results in terms of preservation of sperm motility, proportion of sperm with intact acrosomes, penetration through the zona pellucida and binding to the oolemma. Fresh sperm is diluted with Ham's F 10 solution in a ratio of 1:3 (with the addition of 5% fetal calf serum), centrifuged, then mixed with buffer. The diluted sperm is placed in 0.25 ml of payette, left for 10 minutes at a temperature of 22 °C and manually dipped into liquid nitrogen vapor for 60 seconds, cooled there to -10 °C, and then frozen to -100 °C, lowering the temperature from speed -40 °C/min, then immersed in liquid nitrogen. The sperm is thawed for 10 seconds in air, then for 20 seconds in a water bath at a temperature of 37 °C, after which it is mixed with Ham's F 10 solution. In addition to the above solution, TesT and Tris buffers are used to dilute the sperm. Sperm motility and the number of intact acrosomes decrease after thawing. Use of artificial insemination
Work on artificial insemination of domestic cats is carried out mainly for scientific purposes, since its biology is similar to the biology of wild cats, however, the developed methods of artificial insemination and sperm preservation can be used in cat breeding. The number of breeding animals for many breeds is limited, in particular due to the fact that most cats undergo castration due to behavioral problems (for example, urine marking) that complicate their keeping at home. The lack of breeders, as well as an imbalance in the number of uncastrated male and female cats, sooner or later leads to inbreeding and degeneration, which results in the spread of birth defects and diseases. Freezing sperm allows you to ensure not only its export to any country in the world, but also the ability to obtain offspring even from castrated or dead cats. In addition, artificial insemination significantly reduces the risk of spreading diseases.

Artificial insemination methods
Ovulation induction
In the absence of mating, ovulation is stimulated by injection of human hCG, which increases LH secretion.
Ovulation induction is most effective on day 3 of estrus. Intramuscular administration of 100 IU of human hCG ensures ovulation in most cats; increasing the dose leads to ovarian hyperstimulation and oocyte degeneration. Anesthesia inhibits ovulation if administered after its induction or immediately before ovulation. As an alternative method, intramuscular injection of 25 mcg of GnRH can be used. Artificial insemination with fresh semen
There have been reports of successful insemination with fresh semen (both vaginal and intrauterine). If insemination with sperm diluted with 0.1 ml of saline solution is carried out on the day of administration of human hCG and again 24 hours later, i.e. at the time of ovulation, more reliable fertilization is ensured compared to a single insemination on the day of administration of human hCG. Surgical intrauterine insemination provides the best results when performed 31–50 hours after human hCG administration. Fertilization occurs within 49 hours after ovulation induction. To perform intravaginal insemination, the use of tranquilizers is usually not required.

The length of the vaginal vestibule of a domestic cat is 1–2 cm, diameter 2.5–3.0 cm. A 3.5-gauge French catheter can be used for intravaginal insemination.
It is inserted 45–50 mm into the vagina up to the cervix, the sperm is squeezed out (Fig. 10.6), after which the animal is held in a position with the pelvis raised for 10 minutes. For insemination with fresh sperm, the sperm dose must contain at least 5 x 106 sperm. Table
10.6. Artificial insemination Ovulation induction - 100 IU hCG on the 3rd day of estrus;

Ovulation - 26–29 hours after injection of human hCG;

Fertilization - May occur up to 49 hours after ovulation induction;

Anesthesia - May suppress ovulation;

The total length of the vaginal vestibule and vagina is 45–50 mm.
Artificial insemination with frozen sperm
Full-fledged offspring can be obtained by insemination with frozen (after thawing) sperm. The probability of pregnancy is about 10% with natural and hormonal stimulation of estrus. The low efficiency of this method is probably explained by damage to the acrosomes during freezing and subsequent thawing, even if the sperm have good motility. An important factor is the correct choice of both the timing of the manipulation and the method of insemination: as in dogs, the best results are observed as a result of intrauterine insemination, especially when it comes to the use of frozen sperm. Surgical intrauterine insemination is not practiced in many countries due to ethical concerns. Intrauterine insemination through the cervix significantly increases the effectiveness of this procedure.

Artificial insemination, including the collection and storage of sperm, is not a common method of breeding, but may become so in the very near future.
Fig.
10.6. Vaginal insemination of a cat. Sperm is injected into the cranial part of the vagina closer to the cervix

LITERATURE

Axner E., Strom B. and Linde-Forsberg S. (1997) Sperm morphology is better in the second ejaculate than in the first in domestic cats electroejaculated twice during the same period of anesthesia. Theriogenology,
47
, 929–934.

Axner E., Strom B., Linde-Forsberg C., Gustavsson I., Lindblad K. and Wallgren M. (1996) Reproductive disorders in 10 domestic male cats. Journal of Small Animal Practice
37
, 394–401.

Chakraborty PK, Wildt DE and Seager SWJ (1979) Serum luteinizing hormone and ovulatory response to luteinizing hormone-releasing hormone in the estrous and anestrous domestic cat. Laboratory Animal Science

29, 338–344.

Dooley MP and Pineda MH (1986) Effect of method of collection on seminal characteristics of the domestic cat. American Journal of Veterinary Research
47
, 286–292.

Dooley MP, Pineda MH, Hopper JG and Hsu WH (1991) Retrograde flow of spermatozoa into the urinary bladder of cats during electroejaculation, collection of semen with an artificial vagina, and matting. American Journal of Veterinary Research
52
, 687–691.

Glover TT and Watson PF (1985) The effect of buffer osmolality on the survival of cat (Felis catus) spermatozoa at 5 °C. Theriogenology,
24
, 449–456.

Glover TT and Watson PF (1987) The effects of egg yolk, the low density lipoprotein fraction of egg yolk, and three monosaccharides on the survival of cat (Felis catus) spermatozoa stored at 5 °C. Animal Reproduction Science

13, 229–237.

Linde-Forsberg S. (1990) Achieving pregnancy by using frozen canine chilled extended semen. Veterinary Clinics of North America-Small Animal Practice
21
, 467–485.

Platz CC and Seager SWJ (1978) Semen collection by electroejaculation in the domestic cat. Journal of the American Veterinary Association
173
, 1353–1355.

Platz CC, Wildt DE and Seager SWJ (1978) Pregnancy in the domestic cat after artificial insemination with previously frozen spermatozoa. Journal of Reproduction and Fertility
52
, 279–282.

Pope CE, Turner JL, Quatman SP and Dresser BL (1991) Semen storage in the domestic felid: a comparison of cryopreservation methods and storage temperatures. Biology of Reproduction
44
, 257, 50.

Sojka NJ, Jennings LL and Hamner CE (1970) Artificial insemination in the cat (Felis catus L.). Laboratory Animal Care
20
, 198–204.

Watson PF and Glover TE (1993) Vaginal anatomy of the domestic cat (Felis catus) in relation to copulation and artificial insemination. Journal of Reproduction and Fertility

Supplement
47
, 355–359.

Wood TC, Swanson WF, Davis RM, Anderson JE and Wildt DE (1993) Functionality of sperm from normo-versus teratospermic domestic cats cryopreserved in pellets or straw containers. Theriogenology
39
, 342.

Table of contents

False pregnancy in a cat

False pregnancy in cats, unlike dogs, is quite rare. The cause of false pregnancy is associated with the hormone of the corpus luteum - progesterone, as well as the pituitary lactogenic hormone - prolaction. The corpus luteum in cats functions for 30-45 days. It is generally accepted among experts that this is a natural physiological process that does not pose any danger to the cat’s health. The main signs of false pregnancy are enlargement of the mammary glands, abdomen, manifestation of lactation and maternal instinct; the cat seeks privacy and prepares the nest for childbirth. In some cases, in order to normalize the level of sex hormones in a cat’s blood, it is necessary to resort to sterilization. It must be borne in mind that a false pregnancy can be distinguished from a real one by ultrasound or x-ray examination in a veterinary clinic.

Popular questions

1. How long does heat last? The duration of estrus (heat) is different for each cat. On average, estrus lasts seven days, but can sometimes reach 21 days. If the cat does not mate and does not become pregnant, the estrus may begin again, with two days between estruses.
2. At what age can a cat become pregnant? A cat can become pregnant as soon as it reaches sexual maturity (about four months).
3. At what times of the year can a cat become pregnant? Cats can become pregnant at any time of the year, especially in average climates, but mating and pregnancy occur most often in the spring.
4. How long does pregnancy last in cats? 56 – 71 days. The average duration of pregnancy is 67 days.
5. How many times a year can a cat kitten? Up to five times a year!
6. On average, how many kittens can a cat give birth to at one time? On average, a stray cat gives birth to three kittens, but sometimes six kittens or more.
7. Can a cat get pregnant while nursing kittens? Certainly! Typically, cats go into heat 1-2 months after giving birth, at which time they can become pregnant again. Some cats may go into heat a week after giving birth, which can lead to pregnancy.
8. Is it possible to sterilize cats while they are nursing kittens? Yes. A cat that is spayed while nursing kittens will continue to produce enough milk for her kittens. Some veterinarians prefer to wait until the cat has stopped nursing her kittens before operating, because mammary gland development during nursing can make surgery difficult. If the cat can be kept indoors away from male cats, you can wait to have her spayed until she is no longer nursing kittens (then the entire family can be spayed or neutered). If the cat cannot stay away from cats while feeding, then she needs to be sterilized as soon as possible. Return your cat to kittens as soon as possible after surgery. If the lactating cat is feral and must be captured, it is advisable to capture the kittens as well (if possible), or wait until the kittens are at least six weeks old, so as not to leave the kittens without their mother for a long time.
9. At what age do non-sterilized cats stop producing kittens? Unlike humans, cats do not go through menopause. Although fertility gradually declines over time, there is no specific age after which a cat can stop becoming pregnant.
10. Can cats from the same litter mate and create kittens? Yes. It is for this reason that cats and female cats from the same litter living together must be spayed and sterilized before four months.
11. Is it okay to let your cat give birth once before getting spayed? No! This will not bring any benefit to the animal. It is easier and safer to spay a cat before her first litter, or better yet, before her first heat. Recent experimental results have shown that spaying a cat before six months of age significantly reduces the risk of mammary cancer.

Video

Signs of beginning labor in a cat

By the end of pregnancy, the cat's belly sag, the pelvic ligaments relax and lengthen by 1/3, and the sacrum becomes retracted. 10-30 hours before the onset of labor, the cat’s pelvis becomes “birthing.” 2-4 days before the onset of labor, the labia and mammary glands swell and enlarge, colostrum may leak from the nipples, and the nipples become more swollen. Viscous, transparent mucus is released from the genital slit. 6-24 hours before giving birth, cats become restless and begin to look for a secluded place. Body temperature 18-24 hours before the onset of labor decreases by 1-1.5° C. (If it was previously 38°, then it becomes 37°). During childbirth, body temperature returns to normal.

Cats can produce from 1 to 10 kittens per litter.

How to determine the number of kittens in a pregnant cat

If you want to find out how many kittens a cat will give birth to, there are several proven methods:

1. Based on genetic data. How many babies did your pet's mother have in her litter on average? Most likely, this factor was inherited from her. If the cat's grandmother had an average of 6 goals at a time, then your pet will have the same number. She is unlikely to give birth to more than her ancestors gave birth to.
2. Folk way. Count how many mammary glands the cat has swollen during pregnancy? Then subtract two from their number. Of course, no one can guarantee the effectiveness of such a result, but it is used quite often.
3. Scientific method. One of the simplest and most common ways to find out how many kittens a cat will give birth to today is ultrasound. It is done 10-14 days before birth, this will allow you to determine the exact number of fetuses.

Under no circumstances should you try to count the number of fetuses in a pregnant cat by palpating her. This can affect the health of future babies and cause stress for the mother herself. The maximum that can be done is to gently stroke the tummy if the cat exposes it herself.

Keep a close eye on your pet. If she had more than one partner at the beginning of her pregnancy, then she is likely to give birth to both fathers, which means that the number of cubs will be greater than usual.

How to properly feed a pregnant cat?

Feeding a pregnant cat should be complete and balanced. In the first weeks of pregnancy, the cat's feeding should be increased by 10% of the usual norm. You need to feed your cat little by little, but often, because due to the growing uterus, there is pressure on the stomach and digestion of food will be difficult. At the same time, you cannot overfeed a cat, as it may become obese, and the kittens themselves will be quite large, which is fraught with pathological birth. From the 7th week, the cat begins to eat less; she needs to be given food 3-4 times a day in small portions. If your cat eats dry food, then she needs to be switched to a special diet for pregnant women. If your cat is on a natural diet, then after consultation with the clinic’s veterinarian, a vitamin and mineral complex is included in its diet.

How does a cat's pregnancy proceed externally?

In the first trimester, a pet's pregnancy can be completely invisible to the owners. Even an experienced veterinarian will not be able to determine it at this time. But by the end of this period, the embryos in the abdomen have already grown to a decent size - 1-2 centimeters, so physiological changes begin to occur. There is, as a rule, one exception - if you know the exact date of mating between a cat and a cat.

In the second trimester, hormonal levels change, which leads to morning sickness. The belly is growing, but for now the owners may not notice it with the naked eye. But a visit to the veterinary clinic will answer many questions: the doctor will be able to establish the fact of pregnancy.

The second half of the gestation period is the most active in terms of changes in the body. After the fourth week, you can feel the kittens with your palm. If there are a lot of them in the tummy, then the animal’s posture will change. The pet will take the shape of a “donkey” due to the sagging of the back.

In the last days before giving birth, the cat begins to show a desire to nest. She sleeps a lot, and her vigorous appetite gives way to a sluggish interest in food.