1 dog, usually referred to as domestic dog, also called dog, is a common canine mammal. Often called "the most loyal friend of mankind", it is also the pet with the highest feeding rate. Its life span is about ten to thirty years. If there is no accident, the average life expectancy of small dogs is longer. 2 1 Dogs are carnivores. When feeding, it is necessary to prepare more animal protein and fat in the feed, supplemented by vegetarian ingredients, in order to ensure the normal development and health of dogs. Dog's digestive tract is shorter than that of herbivores, and the content of hydrochloric acid in dog's stomach ranks first among domestic animals, and the absorption capacity of intestinal wall thickness is strong, so it is easy to digest meat food and suitable for digestion. Dogs belong to the family, and they don't chew very much, which can be described as "wolfing down". If you want to feed coarse fiber vegetables, you'd better chop them up or cook them. The dog's defecation center is not developed enough to defecate while exercising, so give it a certain defecation time. Dogs like to bite. This is also the habit of biting prey in the original ecology. When feeding, you should often feed it some dogs with white dog bones (dogs should not feed it with poultry bones, and it is best not to feed pigs and cows, otherwise they may choke to death) to facilitate grinding their teeth. Dogs have unique self-defense ability. After eating toxic food, they will cause vomiting reaction and spit out toxic food. In hot summer, the dog's mouth is wide open and its tongue is long, and it relies on the evaporation of water in saliva to dissipate heat. When dogs live in groups, there is also a "hierarchy" and a master-slave relationship. Establishing such an order can maintain the stability of the group and reduce the struggle caused by the struggle for food and living space. When a dog is lying down, he always turns around to see if there is any danger around him, and then he will sleep peacefully after making sure there is no danger. 10 Dogs like to be caressed on their necks and backs. Try not to touch the top of your head, because it will make it feel depressed and dizzy. Besides, you can't touch your ass or tail. "Dogs can't change but eat shit" is the biggest vice of dogs and must be corrected. 1 1 The dog's code of conduct for strangers is to judge the strength of the opponent according to the height of the line of sight. When a stranger approaches, the oppressive feeling of coming down from above will make him uneasy. If you keep a low profile, he will accept you. If it is lower than the height seen by its eyes, it will make it feel more secure. The dog's weakness is on the right, and it will make actions to protect the right. When it is cornered, it will lean its right side against the wall and its left side will face the enemy. This habit is a dog's innate instinct. A dog showing its belly is [1] to show obedience and surrender to the other side. 12 dog society has certain rules. They will never attack opponents who fall down and show their bellies. When a dog sleeps with its stomach down, it shows that it is very relieved or trusting, so that people can see or touch its stomach. By the way, the only cruel animals that can violate the same kind of agreement are humans and birds. Dogs like people more than their peers, not only because people can take care of them and give them food and shelter. The main reason is that dogs keep company with people and build feelings. Dogs have a strong sense of protection for their owners. Some dogs rescue children from water, burning houses or under cars. A dog will help its dog friend who is in pain or injured. 13 dogs have territorial habits, that is, they occupy a certain range and protect them from other animals. They use anal gland secretion to make feces have a special smell, sweat secreted by sweat glands between toes and pictures of scratching on the ground with hind legs as territorial markers. Dogs are very jealous. When you notice the new dog and neglect to take care of it, it will get angry, disobey its habit and become irritable and destructive. Dogs also have vanity and like to be praised. When it does a good thing, or does some tricks, you clap your hands to praise it and touch it, and it will be as satisfied as a full meal. Dogs are also shy. If they do something wrong or have their hair cut too short, they will hide somewhere until they are hungry. 14 in terms of memory, dogs never seem to forget the voices of people they have been close to, and they can also remember the places where they have lived. However, some people think that dogs rely on sensory sensitivity to recognize the voices of acquaintances and know the location. Dogs like to smell anything. Smell territorial signs, new food, poison, feces, urine and so on. When the dog is wandering outside, we often see it constantly urinating or squatting down and scattering feces on the road. And it walks by these "smelly marks". Dogs like to chase animals. Like hunting small animals. Chase rabbits, cats, sheep, etc. Even chasing humans, people use this characteristic of dogs to drive away cattle and sheep and protect themselves. 15 When dogs are sick, they instinctively avoid humans or other dogs and hide in the dark to recuperate or die. This is an "atavism". The ancestors of dogs lived in groups. If any dog in the group is sick or injured, other dogs will kill it to avoid all the trouble or pain after falling behind. This should attract the attention of dog owners or breeders and should be treated by veterinarians in time. Dogs like alcohol the least. When giving injections to dogs in the veterinary hospital, behave yourself first, and then rub alcohol. As soon as the dog smells alcohol, its hair immediately stands up and growls. Dogs are afraid of fire, so they don't like anything that smokes, such as lighting matches and smoking. 16 The movement of the dog's tail is also a kind of "language". Although different types of dogs have different tail shapes and sizes, their tail movements express similar meanings. Generally, when the host is excited or happy, he will shake his head and tail. The tail not only swings from side to side, but also keeps spinning. The tail is tilted up to show joy; A drooping tail means danger; The tail does not move, indicating anxiety: the tail is tilted, indicating fear; Shake your tail quickly and horizontally, symbolizing friendliness. The movement of the dog's tail is also related to the owner's tone. If the host speaks to it in a friendly voice, it will wag its tail to express its happiness; On the other hand, if the owner's voice is harsh, he will still pick up his tail and make unpleasant behavior. That is to say, for dogs, human voice is just a sound source, an acoustic signal, not a language. The smile of human beings and the wagging of a dog's tail are similar forms of communication, but it was not until I read Cuillo's The Intelligence of Dogs that I realized that dogs wagged their tails only at living objects. The doctor said that a dog lying there alone would not wag its tail, even if there was an inanimate object in front of it. A dog may like to eat certain foods, but it won't wag its tail at them unless other creatures are present. Jean craighead george has the same view on how to talk with your animals: "Dogs wag their tails at creatures, which is equivalent to human smiles. They are only born to people, dogs, cats, squirrels, even mice and butterflies, not creatures. Dogs don't wag their tails when eating or sleeping, cars, sticks or even bones. " However, this statement is still controversial. Bi Foucault, a scholar who has a good knowledge of canines, told me that this is actually wrong: he once saw a dog wagging its tail while eating in another room. Is it because the dog found someone watching it? Unlikely. My veterinary friend Federman in Berkeley agrees with Bikov. In any case, a dog's tail can convey a lot of information. Even if dogs wag their tails, whether biological or abiotic, it still can't change the fact that dogs like close emotional contact, which is the main reason why they wag their tails when they see us. No one will misunderstand their meaning. Just watch the dog wagging its tail at a stranger, and you will know that many, if not most, people will immediately have a warm and even embarrassing conversation with the dog: "You cute, sweet and beautiful little guy, look how smart and wonderful you are!" Come on, give me a kiss. The dog refused, so he obeyed. If you observe dogs for a long time, you will find that dogs sometimes eat grass. So why do dogs sometimes eat grass? The gastrointestinal structure of dogs is different from that of people, which is an important reason why dogs eat grass. The dog's stomach is very big, accounting for about 2/3 of the abdominal cavity, but its intestines are very short, accounting for about13 of the abdominal cavity. Therefore, dogs basically use their stomachs to digest food and absorb nutrients, which is easy to digest meat food, but not easy to digest things with "tendons" like leaves and grass. Dogs sometimes eat grass, but eat little and occasionally vomit. Dogs eat grass not to satisfy their hunger like cows and horses, but to clear their stomachs. When a dog feels indigestion and has a fever, eat some grass, which turns into feces and expels other things in his stomach. Foods that must not be given to dogs: onions and leeks. There are also some foods or objects that are very irritating to the sense of smell. Don't let the dog smell it, which is very harmful to the dog's sense of smell. For a long time, many people thought that dogs could not distinguish colors. Recently, researchers found that dogs can distinguish different shades of gray from certain colors, especially blue and purple. The difference between human vision and dog vision is that the dog's eyes react to light differently from human eyes. The human eye reacts to the three primary colors (blue, yellow and red) that produce various colors. Dr Dennis Brooks, associate professor of ophthalmology at the College of Veterinary Medicine, University of Florida, said: "Dog vision is different from human vision; Dogs can't tell colors like people, but they can see some colors. Dogs can distinguish different shades of blue, indigo and purple, but they are not particularly sensitive to high chroma colors such as red and green in the spectrum. Dr. Brooks' research shows that red is dark for dogs and green is white for dogs, so the green lawn is white for dogs. Dog's retina The dog's retina-retina-contains a large number of columnar cells, which is helpful for vision in the dark and detection of moving objects. Another cell in the omentum is the vertebral cell, whose main function is to distinguish colors and subtle differences. The dog's retina has a layer of choroid, which is highly reflective and can improve the dog's night vision ability. Because light enters the eye, it will hit the photoreceptor cells on the retina, but it may also miss and penetrate the retina; But for dogs, because of the choroidal layer, even if the light is missed and does not hit the light receiver, it will still reflect back to the retina, resulting in the so-called second vision. The choroidal layer of dogs is also the reason why dogs' eyes appear yellow, green and red under strong light. A few dogs' eyes lack this layer of structure, but the reason is still unknown. Relationship between vision and breed: short-nosed dogs (such as bulldogs) can see farther depth of field, while long-nosed dogs (such as sheepdogs) have wider field of vision. In addition, the shape of the dog's skull and the length of its nose will also affect its vision. It is generally believed that most dogs have mild myopia. A few people have farsightedness; But the degrees of myopia and hyperopia are all based. Veterinarians can provide eye protection tips for dog owners. When a foreign body is found in the dog's eyes, it should be sent to the veterinarian as soon as possible, and it should not be wiped with cotton swabs or fingers to avoid hurting the eyes. In addition, it is also found that dogs often scratch their eyes, shed tears, blink, red eyes, distracted eyes, colored secretions, or protruding third eyelids. They should also seek medical treatment as soon as possible. Dogs should be forbidden to stick their heads out of the car when taking a car, so as to avoid serious injury caused by the impact of insects on their eyes. When using any products containing alcohol (such as ear cleaner), you should absolutely avoid contact with your eyes. When bathing the dog, avoid the foam of lotion from entering the eyes; When washing around the eyes, you can cover your eyes and make your head lean back slightly to prevent lotion from entering your eyes. In case the lotion gets into your eyes, wash it with plenty of sterile saline and see a doctor if necessary. Marquis of Tibetan Mastiff at 20.0 years old/toy poodle at 0/8 years old/miniature dachshund at 0/5 years old/whipple at 0/4.4 years old/Pomeranian at 0/4.3 years old/American cocker spaniel at 0/4 years old/Song Shiquan at 0/2.5 years old/Kloc-0. +03.3 Beijing Dog 13.3 Hilde Dog 13.3 Border Collie 13.0 Chihuahua Dog 13.0 Foxtrot Dog 13.0 Bajie Dog 12.8 West Highland White Terrier Dog 650 .3-year-old Samoyed Dog 1.0-year-old Samoyed Boxer Dog 10.3-year-old Du Binquan 9.8-year-old Great Dane 8.4-year-old Bernstein Dog 7.0-year-old In addition, the breed's life expectancy is about 12-65448. Second, it growls at the leader German shepherd. In other words, the dog's loyalty to its owner is actually a substitute for the dog's loyalty to its mother or group leader. From the pedigree, modern domestic dogs can be divided into two categories: wolf pedigree and wolf pedigree. The loyalty of dogs of Hu wolf descent is mainly related to the first emotional source, that is, it mainly comes from attachment and trust to their mothers; This kind of mother can be anyone who is friendly to it. The loyalty of wolf-bred dogs is mainly related to the second emotional source, that is, it mainly comes from loyalty and obedience to the dog leaders; This kind of leader, for dogs, is only one in life. In this way, loyalty has different meanings for these two dogs with different lineages. For a dog of Hu wolf descent, the so-called loyalty to its owner means loyalty to all the people who are friendly to it, while for a dog of wolf descent, the so-called loyalty to its owner means loyalty to a master or individual master. A dog of the wolf blood can be loyal to all the people who are friendly to it, so this "loyalty" should be disloyalty to a particular owner. Wolf breed dogs are loyal to only one master in their life, so it can be said that wolf breed dogs are far more loyal to their masters than Hu wolf dogs. The reason why the loyalty of these two breeds of dogs is so different is that the genes of these two dogs are different.