Pig anatomy. Similarities between human and pig DNA

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

The progenitor of domestic pigs is a wild boar belonging to the genus of non-ruminant artiodactyls. Currently, these farm animals are bred in many countries of the world. But they are most popular in Europe, Russia and the states of East Asia.

Pig appearance

From their ancestors, wild boars, domestic pigs do not differ too much. The only thing is that piglets are not usually covered with such thick wool. The anatomy of a pig and a wild boar is almost identical.

The distinctive features of domestic piglets are:

• short build;
• legs with hooves;
• bristle hairline.

An elongated muzzle ending in a heel, which serves when searching for food to loosen the soil - this, of course, is also one of the main characteristic features of a pig. In the photo below you can see how convenient it is for piglets to use this organ of theirs even when kept at home. It is a cartilaginous movable disk.

The shape of a pig's head can, among other things, determine its appearance. In representatives of meat breeds, it is somewhatelongated. In greasy piglets, this part of the body has a more rounded shape.

Pig Anatomy: Musculoskeletal System

Piglets belong to the class of mammals. The skeleton of these animals is represented by about 200 bones. At the same time, the following varieties are distinguished:

• long tubular;
• short;
• long curved;
• lamellar.

The pig skeleton itself consists of several sections:

• skulls;
• neck;
• body and tail;
• limbs.

The muscular system of the pig is represented by smooth muscles and skeletal muscles. The bones in the body of these animals connect the collagen fibers that form the joints. In total, pigs have several unpaired and about 200-250 paired muscles.

Digestive and excretory system

Piglets are practically omnivores. And the digestive system of pigs is developed, of course, very well. Its main departments are:

• oral cavity;
• pharynx and esophagus;
• single chamber stomach;
• large and small intestines;
• rectum;
• anus.

The liver is responsible for filtering blood and neutralizing harmful substances in pigs, as in any other mammals. The stomach of these animals is located in the left hypochondrium, and the pancreas - in the right.

Urinary system

One of the absolute advantages of pigs as farm animals is the highfertility. The reproductive system of boars is represented by the following organs:

• scrotum and testis;
• duct and spermatic cord;
• urogenital canal;
• penis;
• a special skin fold covering the penis - prepuce.

The reproductive system of the female pig is represented by the following organs:

• ovaries;
• fallopian tubes;
• womb and vagina;
• external organs.

The estrous cycle in a pig can last from 18 to 21 days. These animals bear cubs for 110-118 days. One sow can have up to 20 babies. That's even more than the famously fertile rabbits.

The genitourinary system of the pig is also represented by:

• paired buds;
• ureters;
• bladder;
• urethra.

In males, the urethra, among other things, conducts sexual products. In pigs, it opens in front of the vagina.

Nervous system

Pigs are highly developed animals. It is believed that they are similar in intelligence to dogs. These animals, for example, can be easily taught to carry out various kinds of commands. Like dogs, pigs are able to return from afar to the places where they once lived.

The nervous system of these animals is represented by:

• brain and spinal cord with ganglia;
• nerves.

The brain of these animals has two hemispheres with convolutions and is covered with bark. Its mass in pigs ranges from 95-145 g. The length of the spinal cord in these animals can be 119-139 cm.

Cardiovascular system

Like other mammals, the central organ of blood circulation in pigs is the heart. It has a conical shape and is divided into right and left halves by a longitudinal partition. Rhythmically contracting, the pig's heart drives blood throughout its body. Each half of the animal heart is in turn divided by transverse valves into a ventricle and an atrium.

The blood of pigs consists of plasma and red blood cells, platelets and white blood cells floating in it. From the heart through the animal body it flows through the arteries, but returns to it - through the veins. Also, the pig's circulatory system is represented by capillaries, through the walls of which oxygen enters the tissues.

All kinds of foreign particles and microorganisms are neutralized in the body of these animals in the lymph nodes.

Features of the structure of the skin of pigs

The skin thickness of piglets can vary between 1.5-3mm. In purebred pigs, this figure may even be equal to only 0.6-1 mm. At the same time, the subcutaneous layer of piglets contains a very large amount of fat and can reach a huge thickness.

Mature males have a shield on the sides of the shoulder girdle and chest, consisting of compacted bundles with fatty pads. This formation protects wild boars during heat fights.

Hard bristle hairs on the skin of pigs alternate with soft ones. The density of the hairline in piglets of different breeds may vary. ATIn most cases, bare piglets are, of course, bred on farms. But there are breeds that are covered with thick hair, about the same as wild boars.

Analyzers, hearing and vision

The circulatory system of the pig is thus very well developed. The same applies to other organs of piglets. For example, pigs have an excellent sense of smell.

The organ responsible for odor perception in these animals is located in the nasal passage and consists of:

• olfactory epithelium;
• receptor cells;
• nerve endings.

The sense of touch in pigs is carried out by receptors of the musculoskeletal system, mucous membranes and skin. The organs of taste in these animals are papillae located in the oral mucosa. The eyeballs in pigs are connected to the brain by the optic nerve.

The ears of these animals consist of the following sections:

• cochlea;
• conducting pathways;
• think tanks.

Similarities and differences between pigs and humans

Humans, as everyone knows, belong to the class of primates and descended from apes. Purely outwardly, a person, of course, most of all resembles this particular animal. The same applies to the structure of internal organs. However, in terms of physiology and anatomy, a person is quite close to a pig.

For example, like humans, piglets are omnivores. It is believed that they were once tamed precisely because of this. wildwild boars willingly ate the remains of human food. The only difference between humans and pigs in this regard is that the latter have fewer bitter taste receptors in their mouths. A pig perceives sweet and bitter differently than a human.

As you know, the structure of a pig's heart is not much different from a human heart. Doctors even try to use piglets in this regard as donors for both humans and monkeys. A piglet's heart weighs 320g, while a human's heart weighs 300g.

Very similar to human and pig skin. These animals, like people, can even sunbathe. Similar in structure to humans and pigs as well:

• eyes;
• liver;
• kidneys;
• teeth.

In the yellow press, sometimes even flashes of information that sometimes sows in the US and China are used to carry human embryos.

What scientists think

People have been breeding piglets for a long time. And the anatomy of pigs is studied, of course, just fine. However, there is no clear answer to the question of why piglets and primates are so similar, unfortunately. In this regard, there are only a few untested hypotheses. For example, some scientists believe that the pig itself was once descended from a primate.

This incredible hypothesis even has confirmation. On the island of Madagascar, researchers have found fossils of lemurs with a long muzzle with a snout. Like pigs, these animals once tore the ground with their noses in search of food. Meanwhile, instead ofhooves they had a five-fingered hand, like a man's. Yes, and in the embryos of modern pigs, oddly enough, there is the laying of a five-fingered hand and muzzle, like a primate.

Ancient legends are also a kind of confirmation that piglets were once primates. For example, in one of the legends of the inhabitants of the island of Bot, it is stated that in ancient times the hero Kat made people and pigs according to the same pattern. Later, however, the piglets wanted to be different and began to walk on all fours.

Diseases in humans and pigs

Scientists have noticed that the similarity between humans and pigs is not limited to the anatomical structure of the organs. Almost the same in primates and piglets and diseases. For example, in pigs, as in humans, Alzheimer's disease can be diagnosed in old age. Piglets are also very often obese. Can be observed in these animals and Parkinson's disease. The pig in the photo below suffers from just such a disease.

Transgenic animals

The heart and other organs in piglets and humans are similar. However, they are not identical. Experiments on the transplantation of pig organs in humans have ended, unfortunately, in failures due to tissue rejection. To solve this problem, scientists began to breed special transgenic pigs. In order to get such piglets, two human genes are introduced into the embryo and one pig gene is turned off.

Many scientists believe that experiments to breed transgenic pigs in the future may actually help solve the problem of tissue rejection in organ transplants. Confirmationsthis, by the way, already exists. For example, in 2011, Russian surgeons successfully transplanted a heart valve from a transgenic pig into a patient.

Genetic similarity

The anatomy and physiology of pigs is such that, according to some scientists, they are an accurate biological model of a person. According to the structure of DNA, monkeys are, of course, closest to humans. For example, the difference in human and chimpanzee genes is only 1-2%.

But pigs are quite close to humans in terms of DNA structure. The similarity between human and pig DNA is, of course, not so great. However, scientists have found that in humans and piglets, some types of proteins are very similar in composition. That is why piglets were once actively used to obtain insulin.

Recently, in the scientific world, such a topic as growing human organs inside piglets has caused a lot of controversy. Purely theoretically, carrying out such procedures is nothing impossible. After all, the human and pig genomes are indeed somewhat similar.

To obtain organs, human stem cells can simply be placed in a sow's egg. As a result, a hybrid will develop, from which in the future not a full-fledged organism will grow, but only one organ. This could be, for example, the heart or spleen.

Of course, organs grown inside pigs could save the lives of many people. However, many scientists are opposed to this method. Firstly, conducting such experiments, of course, is inhumane in relation to the pigs themselves. Secondly, it is believed that rearing in pigsorgans for humans can lead to the emergence of new genetically modified pathogens that can kill millions of people.

Pig Man Genome

The blood of pigs is biologically 70% the same as human blood. This made possible a very interesting experiment. The scientists took a pregnant sow and injected the embryos with white human blood containing hereditary information. The animal's pregnancy ended in a successful birth.

In the blood of newly born piglets, researchers subsequently found cells containing large sections of both human and porcine chromosomes. This, of course, became a real sensation in the scientific world. Among other things, such cells in the body of piglets were also resistant. That is, they persisted for a long time after birth. Simply put, for the first time, scientists have obtained a stable human-pig genome. Of course, there were few such cells in the body of the test piglets, and the animals were in no way similar to humans. However, the resulting genome contained more than a third of the human material.

Other research scientists

Be that as it may, the anatomy of pigs is well understood, and the idea of using these animals as donors looks quite attractive. Most scientists at the same time believe that there is nothing impossible in this. Researchers in this regard already have quite serious developments. For example, scientists managed to find out that nerve cells taken from the body of pigletsable to put paralyzed people on their feet.

Very high quality contact lenses are already being made from porcine collagen. Cartilage cells from piglets' ears are used to grow artificial breasts. Scientists have also created a pig that produces omega-3 fatty acids that are beneficial to the human heart.