1. Extracurricular knowledge of cats

Cats belong to mammals, carnivores and cats.

A cat's body is divided into five parts: head, neck, trunk, limbs and tail, and the whole body is covered with fur. Cats have fat pads under their toes, so they walk silently.

When catching mice, they don't run away, and there are sharp claws at the toe. The claws can be retracted and extended.

Cats retract their paws when resting and walking, and extend them when catching mice, so as to avoid making noise and dulling their paws when walking. A cat has four fingers on its forelimbs and five fingers on its hind limbs.

Cats' teeth are divided into incisors, canines and molars. Canine teeth are particularly developed, sharp as cones, suitable for killing caught rats, and the chewing surface of molars has sharp protrusions, which are suitable for chewing meat; Underdeveloped front teeth.

cats are quick and good at jumping. There are many kinds of cats. European domestic cats originated from bobcats in Africa, and Asian domestic cats originated from desert cats in India.

mammals, also known as domestic cats. The hearing is developed, the auricle can move towards the sound wave, and can distinguish the direction and distance of the tiny sound.

I have a keen sense of smell. The pupil of the eye can be automatically enlarged or narrowed.

At noon, when the light intensity is high, the pupil shrinks into a slit to reduce the entrance of strong light; At dusk, the pupil opens into a circle to enhance the visual ability. There is a thick meat pad under the cat's toes, which is soft and elastic, and there is no sound when walking, which is convenient for approaching the prey.

a cat's claws are sharp, and it can climb along a tree. Good at jumping.

breed twice a year, with 4-6 offspring per litter. There are many varieties, which are raised all over the world.

Cats are carnivores. After long-term domestication, they are docile and close to people. Keeping cats and catching mice is a traditional method of biological control.

The average life span of cats is 12 years, and the longest-lived cat recorded in literature lives to 3 years old. Cats average 7-8 months, reach sexual maturity age, and the sexual cycle is 15-28 days; The suitable breeding age for cats is 1-18 months, 6-68 days of pregnancy and 6 days of lactation. The normal body temperature of cats is 39℃, and the general range is 38-39.5℃ (rectal temperature). The heartbeat frequency is 13-14 beats/min for young cats and 1-12 beats/min for adult cats; Breathing frequency is 2-3 beats/min; Total blood volume accounts for 6.2% of body weight, red blood cells are 8 million/m3 (the normal range is 6.5 million ~ 9.5 million/m3), and white blood cells are 16,/m3. Are blue-eyed cats deaf? As we have said, cats are very sensitive to hearing, and their function of locating sound and adjusting the balance of the body by the inner ear are better than those of people. However, cats, like other animals, have congenital and acquired deafness.

Some people say that cats with blue eyes can't hear, but this is actually a misunderstanding. For example, most forced cats have blue eyes, but the proportion of deafness is very small.

However, statistics show that cats with white hair and blue eyes have a high proportion of deafness, which is probably related to genetic factors. The occurrence of congenital deafness's syndrome is mainly caused by the gene abnormality on the frequently stained body, which leads to the hypoplasia or underdevelopment of Corti's organ, cochlear spiral ganglion and other organs, resulting in deafness.

However, cats with congenital deafness's disease can't really "hear" any sound. They can still "hear" some sounds, but only through the meat pads under the paws of their limbs, not with their ears. Under normal circumstances, there are quite a lot of tactile receptors in the cat meat pad, which can sense the tiny ground vibration, and cats can use it to detect the mouse activities in underground rat holes.

Deaf cats have more receptors in their meat pads, so even if some sounds make the ground vibrate slightly, they can be "heard" by cats. In addition, deafness rarely affects the balance function of cats, so that combined with normal vision, deaf cats can grow and develop very healthily.

□■ The characteristics of the cat's coat system The most striking thing about a cat is its beautiful coat. Coat and skin not only constitute the beautiful appearance of cats, but also have very important physiological functions.

Skin and coat are a solid barrier for cats, which can prevent the loss of water in the body, resist some mechanical injuries and protect the body from harmful physical and chemical effects. Skin and coat have good thermal insulation performance in cold winter days, which makes cats have strong cold resistance.

In summer, the coat is a big radiator, which can lower the body temperature. There are many receptors in cat skin that can feel the changes of internal and external environment.

receptors can feel one or several kinds of * * *, such as cold, heat, touch, pressure and pain. Cat hair grows from the hair follicle of the skin, and the hair follicle is slender and bag-shaped.

There are two kinds of cat hair follicles, one is an isolated hair follicle with only one hair, and the other is a compound hair follicle with multiple hairs. Cat hair follicles are mainly composed of composite hair skirts.

Therefore, cats have a dense coat, about 2 hairs per square millimeter. Coat can be divided into needle hair and fluff.

There are sebaceous glands and sweat glands in cat skin. The secretion of sebaceous glands is oily, which can make the coat bright and smooth.

The sweat glands of cats are underdeveloped, so they can't participate in thermoregulation like human sweat glands. Cats dissipate heat through skin radiation or breathing.

□■ The respiratory system of cats includes nasal cavity, larynx, trachea, bronchus and lungs. The nasal cavity is divided into two parts by the middle diaphragm, the inner surface is covered with mucous membrane, and the back of the nose is covered with olfactory mucous membrane with olfactory nerves, which is the olfactory part of cats.

The larynx is composed of thyroid cartilage, cricoid cartilage and epiglottic cartilage, and its skeleton is also the vocal organ. The laryngeal cavity is divided into three parts.

the upper part is the vestibule of the larynx, and its tail edge is a false vocal cord, which can make a "gurgling" sound when it vibrates. The cavity between the false vocal cords and the true vocal cords is the second part of the larynx.

The third part is the cavity between vocal cord and cartilage ring, which is very narrow. Trachea and bronchus are the passages of respiratory tract. The wall of trachea is supported by cartilage ring, and the inner surface is lined with mucous membrane of fibrillary epithelium.

The cat's lung is divided into two lobes, and the right lung is larger than the left lung. The lung weighs about 19 grams, and the total area can reach 7.2 square meters after the alveoli are expanded.

healthy cats breathe in the chest, that is, the chest and abdomen rise and fall at the same time, and the number of breaths per minute is 15 ~32. After the ambient temperature increases or activity, the number of breaths can increase physiologically.

□■ The purr of a cat When a cat sleeps and makes out with its owner, it is often possible to hear the sound of "purring, purring" like snoring in the cat's throat. In fact, this is the sound made by the cat's false vocal cords when they vibrate.

The skeleton of a cat's throat consists of thyroid cartilage and cricoid cartilage. The cat's laryngeal cavity is divided into three parts, the upper part is the laryngeal vestibule, and the tail edge is the false vocal cord.

The cavity between the false vocal cords and the true vocal cords is the second part of the laryngeal cavity. The third part is the cavity between vocal cord and cartilage ring, which is very narrow.

When a cat is intimate with a person, the false vocal cords vibrate.

2. What are the visual knowledge of cats?

There are many mysteries hidden in cats' eyes.

Cats are good at foraging at night. From this point of view, the acuity of cats' eyes is different from ours, and it seems to be more insightful than ours. Cats do have a better perception of external things than us. Is this also related to their eyes? As the saying goes, the eyes are the window to see the world. What kind of mystery is hidden in this window of the cat?

At the birth of a kitten, the visual system is underdeveloped. The development degree of cat's eye at birth is equivalent to that of a human fetus of 5 months, and it needs to continue to develop for 5-14 days (8 days on average) after birth. At first, the eyes were only slightly opened, but they were completely opened at 17 days (average 9 days).

Because cats have large lenses and corneas, their eyes can collect more light. Because of the special structure of the fundus (more rod-shaped cells and more layers of retinal sensitive cells), cats can collect 1.5 times as much light as people and can see objects only with 1/6 of the light of people. When it is too bright, in order to reduce the light entering the eye, its pupil will become a narrow slit. Its visual acuity is only 75CM. Although it is nearsighted, cats are extremely sensitive to moving objects, with a limit of .4cm/ s..

at one time, people thought that cats were color blind and could only see shades of black, gray and white. However, the current scientific research proves that this view cannot be established. Because experiments have proved that cats can distinguish colors after training, although it takes a long time. Many scientists believe that cats don't care about colors. Although they can see colors, they don't give them any meaning. Binocular vision is very important for hunting animals such as cats. Because it must be able to accurately judge the mileage in order to calculate the distance to the hunting target. When the visual fields of animals' eyes overlap, the stereoscopic effect can be produced. The larger the overlapping range, the stronger and more accurate the stereoscopic effect will be. Cats' ability to judge distance is not exactly as accurate as that of humans, but it is better than dogs. The overlapping range of visual field of human eye is much larger than that of cat's eye, while that of dog's eye is smaller than that of cat's eye.

The difference between what people see and what cats see is that cats are yellow-blue blind. As for green and red, they can only be yellow in the cat's eye.

The binocular visual area can accurately locate the target, so it is very important for carnivores to hunt. Because of the cat's head shape and the position of eyes, the visual range of each eye is 155-28.5 degrees, which is about 9-13 degrees overlapping, that is, the binocular visual area. Interestingly, Siamese cats (except esotropia cats) have no binocular vision area, so it is more difficult for them to locate objects.

Cat's eyes can be roughly divided into three types in appearance: round, inclined and almond. The colors are basically green, golden yellow, blue and bronze. However, there are different shades among these basic colors.

Compared with people, cats have a wide field of vision, and both eyes have the same field of vision and separate fields of vision. Single vision has no sense of distance, * * * has a sense of distance with vision. The individual visual field of each eye of a cat is above 15 degrees, and the co-visual field of both eyes is above 2 degrees, while the visual field of a person is only about 1 degrees. Cats can only see things with changing light. If the light doesn't change, cats can't see anything. Therefore, when looking at things, cats often have to turn their eyes a little left and right to make the scene in front of them move to see clearly.

The contraction force of the cat's pupillary sphincter and pupil dilators is very strong, and the adjustment range of pupil dilation and contraction is large and fast. Therefore, it can quickly adjust the pupil size according to the intensity of light in the external environment, and focus well to obtain the best visual effect. Cats have the best eyesight in the daytime. At night, as long as there is weak light, their pupils can be greatly dispersed, even to the highest limit. However, even this sensitive cat's eyes can't see in a place where there is no light at all or in the dark night. But as long as there is weak light, the cat's eyes can immediately amplify the light by 4~5 times, which not only makes the limited light completely enter the eye, but also can distinguish the dim objects through the rod cells with dark vision and low light vision on the retina, so that things can be seen. In addition, there is a triangular reflective cell layer in the upper half of the cat's eye sphere, which has the function of reflecting light and can increase the amount of light reaching the retina, thus improving the night vision ability. This wonderful method of enlarging light is a very important physiological feature for the ancestors of cats who used to walk at night thousands of years ago.

For species, the color vision of many species has deteriorated several times. For example, rats and dogs, the world of rats is grayish brown, and they can only see black and white photos in their vision, so rat poison can be a colorful warning color, but it has no effect on rats eating it. Most animals will degenerate their unnecessary physiological functions because of their survival, but cats don't, so the world of cats is colorful.

3. Get down on your knees and ask for common sense about raising cats

Actually, it's not difficult to think about cats. As long as the kittens come to your house, they should establish a daily life system, and if possible, cats should have fixed feeding time.

It is best to train kittens to urinate and defecate in the third to fourth week after weaning and eating solid food. Put the cat in a convenient, accessible and quiet place. Often put on it, you can know whether the kitten needs to urinate or not, because it will cock its tail and squat down, so that you can let the kitten urinate in a fixed place in time! But at first, the kitten won't be in a fixed place, and it will be somewhere else. At this time, don't put your nose on the toilet. When it smells this smell, it becomes its fixed toilet place, so, hehe, these places should be thoroughly cleaned. To prevent the kitten from urinating here again

4. Tips for getting along with cats

The happy life of a pet cat needs the careful and thoughtful care of its owner. In the process of getting along with your baby cat, if it is not handled properly, it will bring trouble and trouble to its owner. Therefore, it is very necessary for you to know the skills of getting along with cats. After reading the following tips, I wish you and your cat a happy life!

When dealing with cats, we should pay attention to the following points:

First, we should make friends with cats. When you start to get in touch with cats, don't be eager to be friendly with them. Let them get to know their owners gradually. The best time to approach a cat is when it is eating. You can talk to the cat softly, but don't touch it yet. Get close to it when the cat is relaxed, and let the cat know that you like it very much. Don't make a lot of noise and take sudden actions to scare the cat.

When cats get to know their owners better, they should give them some caresses, but not too much at first. As long as you are patient and gentle, cats will have a good impression on their owners and establish feelings.

Second, to understand the personality of cats, after mastering the general habits of cats, we should also understand the personality of cats, which is conducive to establishing and consolidating the feelings between people and cats.

Every cat's personality is not exactly the same. Some cats like sports, some are lazy, some like to be close to their owners and coquetry, some cats don't like their owners to touch and cuddle them too much, some cats like spherical toys, and some hats are interested in toys like birds. Knowing the cat's personality, you can take targeted measures to enhance your feelings!

Third, don't punish cats often. Cats are different from other animals, and punishment will not play any role in cats. So when the cat hates it, let it know that the owner doesn't want it to do this, and don't beat and scold at will. Otherwise, the cat will think that the owner doesn't like it, feel that there is no warmth at home, and even run away from home. Under normal circumstances, cats of a certain age will know what can be done and what is not allowed after living with their owners for a period of time.

Fourth, hold the cat correctly. Although hugging a cat is a very common thing, if you don't pay attention, either people are scratched by cats or cats are injured, or even cats are disabled for life.

Before hugging a cat, you should be familiar with the cat, pat the cat's forehead or touch the cat's back. Depending on the size and weight of the cat, you can use one hand or two hands to grasp it. Never scratch your ears, tail or limbs. If you scratch the ear, it is easy to break the ear bone of the cat and cause disability. Cats can easily bite you by scratching your limbs. Cats' tails are very sensitive, so pulling their tails or stepping on them can easily lead to attacks from cats.

5. tips on raising cats

cats are easier to raise, even if they live in a building and don't go out.