МИНИСТЕРСТВО СЕЛЬСКОГО ХОЗЯЙСТВА РОССИЙСКОЙ ФЕДЕРАЦИИ

Фгбоу во «санкт-петербургский государственный университет ветеринарной медицины»

Факультет ветеринарной медицины

Очная форма обучения Кафедра иностранных языков

Реферат

По дисциплине: Иностранный язык «ANATOMY AND PHYSIOLOGY OF RAT»

Выполнила:

Борохович Светлана Сергеевна, студентка 1 курса 4 группы

Проверил:

Горляков П. Ю.

Дата:

Подпись:

Санкт-Петербург 2023

Content

Introduction………………………………………………………………...............

1. The skeletal system of rat.…………………………………………..…………..

2. The muscular system of rat …………..………………………..…………….....

3. The nutrition of rat……………………………………………………………….

4. The digestive system of rat……………………………………………………..

Conclusion……………………………………………………………………..….

Literature…………………………………………………………………….…….

Introduction

Rats appeared on Earth 30-40 million years ago, in Southeast Asia, long before the most distant human ancestors. First in Ancient Kip, then in India. In the age of Great Discoveries this rodent very quickly settled on Earth.

Rats represent a genus of rodents and a family of mice, while the family includes more than 60 species of rodents. It is believed that rats are unique mammals whose lives are closely related to the lives of humans. Humans keep ornamental species as pets. The rat is also used as experimental animals for various scientific experiments.

On average, a gray rat weighs 200-250 grams, but the largest of them are up to half a kilogram. The rat has good hearing, a very fine sense of smell and poor eyesight. Despite her short messes, she runs fast. He climbs trees and even walls well, if they are at least a little rough. He swims and dives well. The rat's main weapon is its teeth. These rodents are very mobile and tireless, sometimes even impetuous, if necessary. [2, p. 135-137]

Rats are also known for their ability to reproduce quickly, making them one of the most successful rodents in the world. They can also transmit various infectious diseases, which makes them an object of study for medical and scientific research.

To study an animal like rats from the point of view of anatomy and physiology, I set myself the following tasks:

1) to study the structure of the rat skeleton and analyze the diseases of this system;

2) to study the structure of the rat muscular system;

3) to study and analyze nutrition and necessary nutrients for rats.

1. The skeletal system of rat

Characteristics of the rat skeletal system

The rat's skeleton has an average of 264 bones. It is composed of three skeletal subunits: Appendicular skeleton - the bones of the limbs. Axial skeleton-the bones of the skull, spine, ribs and sternum. Visceral skeleton - the bones that form part of an organ (such as the middle ear ossicles). The appendicular skeleton of a rat refers to all of the bones that are joined to something larger and allow forward or backward movement. They are foreleg (anterior limb) bones and hind leg (posterior limb) bones.

The axial skeleton in a rat consists of the bones in the head and trunk. In the axial skeleton, the skull connects to the vertebral column. Rats have 7 cervical vertebrae, 13 thoracic vertebrae, 6-7 lumbar vertebrae, 4-5 sacral vertebrae and 25-30 cauda vertebrae. Rats have thirteen pairs of ribs. The first 9 of these are attached to the sternum by costal cartilage. The next three pairs are variably attached to each other and the sternum and the thirteenth pair are floating ribs. The major parts of a rib are the head, neck and tubercle. Collectively, the spine, ribs, and sternum form the thorax (rib cage) that houses the heart and lungs.

The skull is elongated, which determines the pointedness of the rat's muzzle. The rat skull consists of 11 paired and six unpaired bones and is divided into the facial and brain parts. In the nasal cavity, a large area is occupied by the olfactory epithelium.

When looking at the skull of a rat, it is noticeable that it is very elongated, the zygomatic arches are not widely spaced. The wider back part of the skull is called the medulla.

It is narrowed in the area of ​​the eye sockets and widens again in front of the latter. In front of the preorbital expansion, the facial part of the skull begins, which also includes the lower jaw.

The skull serves not only to protect the brain and sense organs (smell, vision, hearing); The facial part of the skull also serves to capture food. The latter function leads to the development of powerful muscles attached to the skull. The parts of the skull that perform different functions develop independently of each other. The brain part of the skull develops from the anterior sclerotomes, which form a connective tissue membrane around the brain and sensory organs. The facial (more precisely, visceral) part of the skull comes from the visceral arches that appear in the walls of the anterior part of the embryonic intestine. The skull goes through three stages in its development; membranous (connective tissue), cartilaginous and bone. [3, p. 160]

The rat also has limbs, including front legs with shoulders, elbows, radii and metacarpals, and hind legs with hips, knees, legs and feet. The rat's tail is made up of many vertebrae and serves to balance and transmit signals.

The rat's skeleton has adaptations to their lifestyle, such as the ability to burrow and hide in narrow spaces.

Experts divide the rodent’s body into 3 sections: dorso-thoracic, lumboabdominal, sacrogluteal.

The limbs of the animals have five fingers. They are larger on the feet than on the hands. The soles and palms are characterized by the absence of hair. [3, p. 188-189]

The tail of rodents is thick, accounting for 85% of the total body length. The female has a longer tail. The surface is covered with scaly rings and yellow fat. Instead of fur there are bristles.

Rat's skeletal design is very similar to ours, although there are two significant differences. First, the human spine has 4 bends, arches of the foot and massive leg bones, which is associated with upright walking. Second, the cerebral part of the human skull prevails over the facial, unlike the rat.

Diseases of the rat skeletal system

1. Osteosarcoma is a malignant tumor that is formed from bone tissue; it is characterized by rapid development and early appearance of metastases. In case of damage to the limbs, the animal stops actively moving, may even stop getting up on its feet. When the skull and ribs are affected by palpation, a dense thickening on the bone is clearly felt. Causes of malignant tumors:

-chemicals;

-physical (ionizing radiation, ultraviolet irradiation, high temperature, mechanical impact);

Osteoma can easily be confused with a bruise or arthritis, so the veterinarian makes a final diagnosis only after studying the results of cytology and x-rays of the affected area.

Treatment is carried out surgically, but osteosarcoma is a serious disease, most rodents cope poorly with it and die within six months.

2. Osteoporosis is the most common metabolic disease of the skeleton, characterized by an imbalance of bone remodeling processes. The main cause of osteoporosis is a lack of vitamin D and calcium due to metabolic disorders.

Osteoporosis can be treated only at an early stage, when bone fragility is not yet very pronounced, and deformations and other pronounced symptoms are not observed in the body. [8]

3. Osteomyelitis- purulent-necrotic process that develops in the bone and bone marrow, as well as in the surrounding soft tissues, caused by pyogenic bacteria or mycobacteria. Rarely inflammation develops due to violations of the blood supply to the bone. Local osteomyelitis is often caused by the formation of bacterial biofilms on implanted materials and is accompanied by infection of adjacent bone tissues, followed by osteolysis and implant rejection.

4. Fractures in rats. The most common injury is considered to be a tail fracture in a rat, which occurs as a result of being pinched by the cage door. It is not uncommon for owners or family members to inadvertently step on a rodent.

Causes of injuries:

-falling from height;

-improper restraint of the animal;

-damage to limbs from the cage or bedding, Improper transportation;

-competition with other animals;

-characteristic signs of bone fractures in rodents;

-impairment of the ability to support a limb;

-hyperemia and swelling of soft tissues;

-pathological mobility of bone segments in the fracture zone;

-damage to soft tissues and gaping bone fragments in the wound.

Diagnosis and treatment of fractures:

The first and most important step in the treatment of bone fracture in rodents is to carefully assess the patient's condition and identify associated systemic disorders. The following are mandatory: X-ray and ultrasound examinations of the chest and abdominal cavities, for the presence of hidden injuries, as well as a complete neurological examination, in order to exclude additionally developing neurological disorders. [1, p. 34]