Discover the Top 7 Animals With the Highest Blood Pressure

Giraffes

For humans, a normal systolic blood pressure is 120 millimeters of mercury (mm Hg) or lower. On the other hand, a giraffe’s blood pressure can range from 180 to 300 mm Hg. The reason giraffes have much higher blood pressure than humans is due to their long necks. A giraffe needs to pump blood all the way up its towering neck to reach its head. To do this, the blood pressure in a giraffe’s heart has to be high. 

Amazingly, giraffes don’t suffer the same consequences of hypertension as humans. Research has shown that giraffes do experience a thickening of their left ventricle (one of the four chambers of the heart) due to their high blood pressure. In humans, this could be fatal. But research has shown it’s not the same for giraffes. Despite the thickening heart muscles, a giraffe’s heart stays healthy. Researchers are studying how this works in giraffes with the hope it may someday lead to medical advancements for humans.

Bears

Bears are another animal with high blood pressure. Research has recorded active black bears (not in hibernation) with a systolic blood pressure of 170 mm Hg. Grizzly bears were recorded at an even higher rate of 253 mm Hg. Intriguingly, scientists have been studying bears’ heart health for clues on treating diabetes in humans. 

As bears prepare for hibernation, they eat tens of thousands of calories per day and put on so much fat they would be considered obese in human terms. The bears must put on enough fat to survive six months of hibernation, where they lose a third of their body weight. However, unlike humans, bears don’t get diabetes or suffer other poor health effects from putting on all that extra weight. Scientists have discovered that bears can control their resistance to insulin, by turning it off or on. Someday, researchers may find the key to helping humans with diabetes by learning more about the heart health of bears. 

Birds

To be able to fly birds need large hearts to meet their oxygen demands. The heart of a bird is 50 to 100% larger than a mammal of a similar size. Furthermore, birds need to be able to pump blood to their brain, wings, and flight muscles. Because of this, a bird’s blood pressure can range from 108-250 mm Hg, depending on the species. Below are some examples of various blood pressure readings in birds. 

• Great Horned Owls (232 mm Hg)
• Canary (220 mm Hg)
• Red-tailed hawks (220 mm Hg)
• Canada Geese (177 mm Hg)
• Wild turkey (193 mm Hg)
• Starling (180 mm Hg)
• Duck (162 mm Hg)

Birds are able to sustain high blood pressure because they have stiffer arteries that improve blood flow and faster heart rates. For example, a hummingbird’s heart can beat 1,260 times per minute. 

Elephants

Elephants weigh from 6,500 pounds to 12,000 pounds. Unsurprisingly they also have large hearts. An African elephant’s heart is one of the largest among mammals that live on land. Furthermore, this massive heart must pump blood through veins that can reach 10 feet in length. To do this, an elephant’s blood pressure must be high, otherwise, the veins would collapse. Elephants have a systolic blood pressure of 180 mm Hg. However, to counter this high blood pressure, elephants have a low resting heart rate. An elephant’s heart at rest beats about 30 times per minute, compared to a human heart at 60 beats per minute. 

Interestingly, when a human lies down to rest, their blood pressure goes down. However, it’s the opposite for elephants. When elephants lie down the weight of their body reduces their lung capacity. This means their heart has to beat faster and blood pressure must increase to get oxygen throughout their body. 

Horses

Horses are large, powerful animals. Although horses vary in size, the average horse weighs 800 to 1,200 pounds and stands five feet tall. The horse’s heart must work hard to pump blood to its head. The horse heart counteracts the negative effects of high blood pressure by having a very low resting heart rate. A horse’s heart rate can drop to 30 beats per minute at rest but rise to 250 beats per minute while galloping. Horses are extremely athletic animals with efficient hearts. Their heart rate lowers quickly after exercise, which is a sign of excellent fitness. 

Often, horses will only get their blood pressure measured during surgery. However, research has been done recording blood pressure on standing and awake horses. The study showed the average horse’s systolic blood pressure to be 169 mm Hg.

Cows

Although the average blood pressure of a cow is not commonly recorded, research has been done showing that awake and alert cows have a systolic blood pressure of 157 mm Hg. This is a little higher than a human’s average blood pressure of 120 mm Hg. 

On average, cows weigh about 700 to 1,760 pounds, and cows have large hearts to pump blood throughout their massive bodies. While a human heart is about the size of our fist, a cow’s heart is the size of a human head. Tissue from cow’s hearts is sometimes used to create a replacement valve for a person with heart damage. 

Greyhounds and Other Sighthounds

In dogs, a systolic blood pressure of above 160 mm Hg is considered pre-hypertension. However, for greyhounds and other sighthounds, such as deerhounds, a higher systolic blood pressure is normal for them. A dog’s blood pressure is measured in a similar way that humans get their blood pressure taken at the doctor’s office. An inflatable cuff is placed tightly around the dog’s foreleg, foot, or tail. Interestingly, greyhounds not only have higher blood pressure than other breeds, but their heart is larger. Their large heart efficiently pumps their blood for greater circulation while carrying more oxygen to their muscles, allowing them to run fast. 

Another interesting fact, greyhounds may suffer from “white coat syndrome” in the same way that people can. This happens when the anxiety of being at the doctor’s office (or at the vet for the greyhound) causes blood pressure to rise. However, when taken at home, blood pressure readings in the same person (or dog) are typically lower. A way to get an accurate reading is to wait for the dog to calm down and retake their blood pressure toward the end of the vet visit.