The knowledge of physiological characteristics of rodents usually the preserve of zoologists and veterinarians.Also, a clear understanding about how pet provides rapid response to signals of pain and discomfort.
The external structure of the rat
When the outer primary inspection noting the considerable amount of wool on the whole body. It is a sign of this class of mammals. Basic functions of hair:
- thermal insulation;
- participation in the sense of touch;
- protection of the skin from damage.
The body of the animal consists of:
The animal's head is large relative to their body size. The muzzle pointed, the back office is adjacent to the short neck. Skull rats includes 3 sections:
Face is divided into:
- of the orbit;
At the end of the snout vibrissae located bristles designed for touch. For rats characterized by the presence of the ciliary membrane and the red glow of the eyes.
Experts divide the torso of the rodent in 3 sections:
- spinal cord rib;
- the Sacro-gluteal.
The limbs of the animals have five fingers. On the feet they are larger than the brushes. The soles and palms is characterized by the absence of hair.
Thick rodent tail, is 85% of the total body length. The female has a more long tail. The surface is covered with scaly rings, and yellow grease. Instead of wool bristles present.
For female animals characterized by 6 pairs of nipples, two of which are located in the armpits, one on the chest and three on his belly. Outside the pregnancy hidden by thick hair. Floor rats determines by visual inspection of the back: in females the rump is shaped like a triangle, and males differs in the shape of a cylinder.
Mature males can reach a weight of 400 g. females are much smaller.
The skeleton of a rat
The skeletal system of the animal consists of a bony and cartilaginous parts, and includes 264 bones of various shapes and sizes. The skull has an elongated shape. There are several divisions of the spine:
For the vertebral part of the skeleton of the rat is typical of over 2 dozen disks.
Despite the fact that it looks like the skeleton of a rodent completely different than the skeletal system, many scientists argue that when stretching the spine will reduced copy of the human species until the similarity of the location of specific bones.
The location of internal organs
Anatomical Atlas also informs about how a General arrangement of the internal organs of a rodent.
This information can be obtained visually if the autopsy rats. After starting the procedure first opens the diaphragm that separates the chest and abdominal region.
Directly under the diaphragm is the liver of the rat. She has a bright red flower, which partially covers the stomach, which is pear-shaped.
Opened below the bulk of the intestinal tract. It is covered with gland – an organ for the accumulation of animal fat.
A characteristic feature of this species of rodents – the absence of gallbladder. The bile in the duct comes from the liver directly into the duodenum.
But in rodents there is an oblong shaped spleen is located to the left of the stomach.
If you remove the intestines from the abdominal cavity, then at the bottom found a pair of buds in the shape of beans. They are skewed – left deepened under the pressure of the stomach. The ureters lead to the bladder located in the abdomen. There are testes of males and complicated by the structure of the reproductive organs of female rats.
Vascular system clearly represented the inferior Vena cava to drain blood into the heart from the organs of the peritoneum. There he finds the aorta, necessary for proper blood supply to the hind limbs.
When examining the thoracic cavity immediately visible pair of pink lungs and heart with the major vessels. The lungs hang freely in the bronchi, and not attached to the chest. Deeper is the esophagus that connects the throat with the stomach.
Studying the internal structure of rats, it is important to remember that organ as the brain. Like many mammals, it has several departments responsible for mental functions. Experts share the brain of rats into 4 parts, each of which has a complex structure.
Interesting facts about physiology
Veterinarians and biologists, studying the anatomical and physiological structure of rats, noted a number of interesting facts:
- numerous laboratory studies on rodents are explained by the similarity of the physiology of rats and humans;
- animals have no tonsils and large fingers;
- males have the fabric for the formation of mammary glands, but no nipples even in its infancy;
- females have a vestigial penis, which can be used for urination;
- in rats the right and left lung have different structures. In the first there are 4 shares, and in the second only one;
- in rodents, there is an Appendix, which is sometimes confused with frolic inside the tumor;
- unlike people and cats, rats-albinos do not suffer from hearing problems;
- ultrasonic treatment gives the rodents discomfort, but they are likely to endure;
- rodents do not have a lip around the mouth. Instead, over the lower jaw formed by the folded period;
- at fertilization, the male spends 2 seconds, so the contents of heterosexual individuals in the same cell ensures the presence of offspring.
Important! The pain threshold of rodents is very high, the animal gives a signal about the presence of pain only under extremely severe symptoms. This leads to frequent late diagnosis of serious abnormalities, so owners of animals should not be neglected maintenance Pets.