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Question of the Week


Name: Tim
Status: Student
Grade: 6-8
Location: CA
Date: N/A

Question:

Hi My name is junior and iam going to do a project on how many times a cat's heart beats and how many times does a dog's heart beats and I need some help and ideas on how to do this?

Answers from Our Expert Staff

Hello Tim!

Well I think that is a fun project! The way most veterinarians would tell how many times an animals heat beats is to use a stethoscope, which is the same thing human doctors use to listen to your heart. I'm guessing you don't have one of these around, but that's okay because there are other ways to gather an animals heart rate. (You are actually looking for heart rate, which is the number of times a heart beats / unit time. Usually it is recorded in beats/minute). Here are some ideas:

Because every time a heart beats it pushes blood through the body, you can measure heart rate by measuring pulse rate. If you put your figure up to the side of your neck you can feel a pulse; another place to feel your own pulse is on your wrist. If you ever watch medical shows on TV, sometimes you will see an actor place their fingers on the neck or on the wrist of another actor to see if there is a pulse. You can use an animal's pulse in just the same way to measure heart rate. Where to do this is a little bit different. The easiest place on a cat or dog to measure heart rate, in my opinion at least, is on the side of their neck (where you will feel the pulse of their jugular vein).

Now one important thing to keep in mind is that dogs and cats (esp cats) can get stressed if they are being handled in an odd way or if they are scared. Only work with cats and dogs you know, and be sure you are being safe in approaching them and handling them. Just like you an me, if they get stressed, their hearts start to beat faster, and sometimes they will get upset and try to scratch or bite. So the best way to get a representative heart rate in these animals is to be sure they are in a comfortable environment and are relaxed.

You'll want to count the number of pulse beats in their vein for 1 minute, and that will be your beats per minute. You may be able to feel two beats that occur very quickly in a row, one of which is stronger than the other - in this case, just count the stronger beat. If you can't get them to hold still for that long, you can take their heart rate for 30 seconds, and multiple that number by 2. You'll probably want to repeat taking their heart rate a few times to be sure you have a consistent number! Also, it's a good idea to take the heart rate of a number of different animals. What you'll find is that there is a range of heart rates in cats and dogs, and often times, particularly with dogs, the breed or size of the animal effects how fast their heat beats! You'll also notice that in general, the heart rate of cats is a bit higher than the heart rate in dogs.

Just to be complete I should mention that there are some disease conditions where the pulse isn't reflective of the heart rate, and so in general it's not the method that veterinarians use to determine heart rate. In fact, veterinarians sometimes actually determine more than one type of heart rate for a given animal, if their heart is not functionally normally. However, for a healthy animal with a healthy heart, pulse rate can generally be used to determine heart rate, and I think for the project you are taking about, that is a perfectly reasonable method to go about things!!

Good luck and have fun!!

Susannah
Univ. of Wisc. School of Vet. Med.

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