In spite of the popular myth that cows have four hearts, cows have a single heart divided into four sections, just like every other mammal and bird. Cow hearts are larger and more muscular than smaller mammals, so that they can circulate blood around their massive bodies.
In this article, we’ll be learning all about cow hearts including the important differences between cow hearts and human hearts, and busting the myth that cows have four hearts once and for all.
Do Cows Really Have Four Hearts?
No. Cows don’t have four hearts. Cows have a single heart, just like every other mammal, including humans!
Why Do Some People Think Cows Have Four Hearts?
For some reason, there is a persistent myth that cows have three, four, or even seven hearts. There are other associated myths too, such as cows having four stomachs, cows having no teeth, and cows’ legs bending the wrong way.
While none of these myths are true, they must come from somewhere and in fact they do stem from cow anatomy.
Cows hearts are divided into four distinct chambers, two for pumping blood (called ventricles) and two for receiving pumped blood (called atriums).
Although this system is extremely similar to all other mammalian hearts, cow hearts are very large and since cows are commonly consumed for meat, it’s easy to see why people would mistake it for four hearts.
How do we know cows only have one heart?
Since cows are commonly raised for meat, we know their anatomy well.
We know for sure that cows only have one heart because we butcher tens of millions of cattle each year and use every available piece of the cow for meat or food, including the heart.
Cow hearts (and also pig hearts) are commonly used for dissecting in biology classes, since they are relatively cheap and are functionally very similar to human hearts.
3. Eating Cow Hearts
Cow hearts are edible and are commonly eaten across the globe, including in the US where it’s commonly referred to as Beef Heart.
Cow heart, or beef heart is a cheap alternative to pricier cuts of beef, and the meat is characteristically homogeneous, meaning there is very little visible grain in the meat.
It’s usually fried, and is rich in minerals compared to regular steak.
Cow Hearts vs Human Hearts
The biggest difference between cow hearts and human hearts is their size.
Cow hearts are around four times larger than human hearts, but are functionally very similar.
Human hearts are about the size of a large apple, while cow hearts can reach almost a foot in diameter. (Or about the size of a human head)
Cow hearts and human hearts beat at approximately the same tempo (70bpm and 80bpm) and their biology is so similar that heart surgeons often use valves from cow hearts as replacements for human heart valves.
Read More: Why are Cows so fat?
Do Any Animals Have More Than One Heart?
There are no mammals, birds, or reptiles with multiple hearts, but there are some cephalopods including Octopus and Squid which have three hearts.
What are the four chambers of a Cow Heart?
Cow hearts are large, and are split into four distinct sections, leading to the myth that cows have four hearts.
Each chamber of a cow heart performs a specific function, with two chambers for pumping blood (the left and right ventricle) and two for receiving blood (left and right atriums).
This is the same layout as the human heart, although the cow heart is much larger.
The four sections of cow hearts are:
|Right Atrium||Blood flows into a cow’s heart through their right atrium.|
|Right Ventricle||Cows’ right ventricles pump blood to the lungs to become oxygenated.|
|Left Atrium||Oxygenated blood is received back in to the heart from the lungs in to the left atrium.|
|Left Ventricle||The left ventricle pumps oxygenated blood around the cow’s body, before starting the cycle again.|
What are Cow Hearts Used For?
Cow hearts are useful for humans, even once they are no longer useful for the cow.
Cow hearts are used in cooking, in medicine, in education, making food for other animals, and making fertilizer.
The internal organs of livestock including cows are usually called Offal when they are prepared for human consumption.
Offal used to be widely eaten by the working class, where it was known as “peasant food”, however now that modern farming has made meat much more affordable it’s falling out of favor in the west.
When human hearts fail, it can sometimes be difficult to find a suitable donor for heart valves and tissue.
Luckily, cow hearts are very similar to human hearts and cow heart valves can be used as replacements when human hearts fail.
Since cow hearts are widely available due to the meat industry, this saves thousands of lives every year.
As you can imagine, it is not possible for medical students to dissect human hearts all too often.
Instead, medical students and biologists typically dissect and work with cow hearts and pig hearts, since they are more readily available and are so functionally similar to human hearts.
4. Food for Other Animals
Cow heart is much cheaper than beef, and along with other innards are sometimes used for non-human meat products, like food pellets or pet food.
In the past, cow meat byproducts would be rendered down and used to create animal feed which would then be fed back to the cow herd. This practice has largely been stopped due to the potential for the spread of neurological diseases.
Read More: Do Cows Eat Meat?
Offal is much fattier than regular beef, and some parts are so saturated in vitamins and minerals they can even be too toxic to eat. (Although hearts are okay)
When hearts and other innards aren’t going to be used for food, they get rendered down and used in industrial processes.
One of the most common uses is for it to be turned into fertilizer.
To conclude, cows only have one heart, but it is split into four distinct sections, which has led to some misconceptions around the number of hearts a cow actually has.
Cow hearts are very similar to other mammalian hearts, except much larger. Human hearts are about the size of a fist, whereas cow hearts are about the size of a human head.
Cow hearts have lots of uses for humans, including as a food source, medicine, food for other animals, and industrial processes.
Although cows only have one heart, there are a few animals that do have multiple hearts. Notably, cephalopods have three hearts.