Fun fact: What other uses do pigs have besides providing meat for humans?

Pigs are the most common livestock among all livestock. However, compared with cattle, sheep and dogs, it seems that the role of pigs is just to provide us with meat. Since the current role of pigs is so limited, why do so many people raise them? So, in addition to meat, what other uses does pigs have? Let's talk about it today.

01. Currently, the main purpose of raising pigs is for meat.

First of all, we must distinguish between the primary and secondary. Currently, the main purpose of raising pigs is for meat. (Please note the word "currently". The main and by-products are never absolute. For example, in genetically engineered pigs, meat has become a by-product.)

The reproductive performance of pigs is almost invincible among domestic animals. As some netizens pointed out, a sow can provide more than 4 tons of pork a year.

In contrast, other animals such as cattle and sheep cannot reach this level because the breeding time is too long and the output rate is too low, which cannot meet the meat demand of 1.4 billion people.

02. Pig byproducts - xenotransplantation

Secondly, speaking of by-products, pig by-products will have enormous significance in the future, and that is xenogeneic organ transplantation!

One of the solutions to the ultimate problems of humanity is organ transplantation. As long as a person's organs are constantly replaced, one for each damaged one, then in theory, that person can live indefinitely, just like the Ship of Theseus.

But the problem is that we don’t have enough organs at present. China’s organ shortage is 1.5 million per year, but only about 10,000 can be transplanted. This gap cannot be made up for a long time in the future.

The above picture shows that the organ shortage in the United States is increasing, and the same is true in China

In this case, we have to find a source of organs.

It is currently difficult to produce organs of the same type. On the one hand, killing one person to save another is definitely not allowed, so human cloning is a forbidden area. Even the embryo is only 28 days old. In this case, it doesn't make much sense.

On the other hand, artificial organ culture is currently basically unfeasible. What is grown is just a lump of meat. If you want to turn it into a functional organ, you must use the original organ framework. This has also put people who study organs in a deadlock (for example, if you culture a heart, it is just a lump of cardiomyocytes. If you want to achieve a beating heart, the most cutting-edge research is to take out an old heart, wash away most of the cells, and then let the cultured cells attach to it, so you still can't do without existing organs)

In this situation, xenotransplantation has become the most popular topic, and the most popular ones are pigs.

03. Why did you choose pigs?

Why did we choose pigs? After all, pigs are synonymous with being lazy and gluttonous in our minds. The main reason for choosing pigs is that they have the following advantages:

1. Organs are basically similar to humans

On the other hand, cows and sheep are not suitable, macaques are too small, and mice are not even worth mentioning.

2. Pig metabolism is similar to that of humans

Pigs are purely domesticated animals, and their metabolism is basically the same as that of humans, while ruminants such as cattle and sheep are too far away.

3. Pigs are easy to raise

This is also an important reason. In addition to their faster growth cycle than cattle and sheep, pigs are also cheap. For example, it costs more than 100,000 yuan to raise a monkey, while a pig only costs a few thousand yuan.

Since 2017, when scientists solved an important problem for pigs: zoonotic retroviruses, pigs have been on an increasingly smooth path toward organ transplantation, a problem that other animals have not yet solved.

The picture above is the original research, which was published as a cover article in Science.

Therefore, the medical significance of pigs will continue to increase in the future. Of course, at this time, would you still say that this is a by-product of pigs? No, at this time, your main purpose is to raise medical pigs, and meat is a by-product.