Why Do Cats Have a Third Eyelid? Understanding the Anatomy of Cats' Three Eyelids

Cats tend to catch our attention with their elegant actions and amazing eyes. They have a small extra eyelid on each eye that most people don't know is significant for their sight. Some people often wonder, do cats have a third eyelid? And why do cats have a third eyelid? 

Instead of having two eyelids that humans have, cats have three: a third in addition to the upper eyelid and the lower eyelid. This additional covering is what is referred to as the nictitating membrane or simply the cat’s third eyelid.

Knowing about this third eyelid and its appearance can assist you in caring better for your cat and will enable you to detect early symptoms of any disease. We will feature useful ideas and products throughout the process that will benefit your cat's eye health.

A Look into Why Cats Have Three Eyelids: What Is the Third Eyelid?

Learning that cats have three eyelids, not the familiar two, is useful. In the corner of the eye, there's a thin fold known as the third eyelid or nictitating membrane. Though the eyelids on top and below are a darker colour, the third eyelid is not coloured and usually stays hidden, only seen around the eyes when the cat is tired, stressed, or sick.

The inner eyelid of the cat goes over to cover the surface of the eye. These third eyelids are similar in many other animals too, including birds and reptiles. However, the action of the cat's third eyelid is not the same and is easily noticed.

They have special glands at the eyelids that assist in tear production; this maintains a healthy eye and keeps it clean. The teardrops are essential in lubricating and moisturizing the eye of the cat in order to keep it healthy.

People might be confused as they often hear about a third eyelid being named the so-called cat's second eyelid in popular culture. However, in the case of anatomy, it is rather the third eyelid and not the upper or lower eyelid. To learn about the third eyelid in detail and see images, read here to learn more.

Why Do Cats Have a Third Eyelid? Key Functions Explained

A lot of cat owners ask, why do cats have a third eyelid? For the cat's survival and wellness, the upper eyelid serves many different purposes.

1. Protecting the Eye from Harm

Being natural hunters, cats regularly investigate narrow places and face dangerous animals. The third eyelid closes over the eye to defend it from being hurt by small particles during play or a fight.

While blinking blocks the eye entirely, the third eyelid sweeps over the eye while a pet is still seeing, offering a fast way to protect it.

Outdoor cats, as well as active ones, benefit from using this function of their eye. Because it's there, you don't have to worry about accidental abrasion or cuts to your eyes while hunting.

2. Maintaining Eye Moisture and Cleanliness

The presence of the third eyelid ensures your eye does not get dry or itchy by moving your tears over the area. It also removes little particles that might bring discomfort or lead to infections.

In fact, the glands in the third eyelid produce some of the tear film, keeping the cat's eyes lubricated. If cats don't have tears, they may develop dry eyes or harm to the eye's outer covering.

A healthy cornea is supported by proper moisture balance, which keeps inflammation or ulcers away and safeguards vision.

3. Immune Defense for the Eye

Since the nictitating membrane contains lymphoid tissue, it also serves to check the inner surface of the eye and pick out any bacterial or viral invasion in advance. Since this additional lid can combat infections, your cat will not be prone to issues when they get out of the house or come in contact with other animals.

Looking for information on how to care for your cat's eyes? Here are some common cat eye conditions you can learn more about to take care of your feline friend.

When Does the Third Eyelid Become Visible?

A healthy cat's third eyelid will be covered and cannot be seen in most instances. You may realize it when:

● You notice your cat is either relaxed or asleep.

● Something is bothering the cat, and it's possible it is sick.

● An underlying health problem is affecting the eyes.

If you find your cat's third lid is showing up often, it may indicate the cat is dehydrated, has an infection around the eye, has hurt the eye, or is sick elsewhere in the body. If your pet shows any of these signs, you should visit your veterinarian as soon as possible.

What Does It Mean If The Third Eyelid Is Visible All The Time?

If your cat’s third eyelid is visible all the time, there might be an underlying issue:

● Eye problems: An infection or injury can cause the eyelid to show when the eye is inflamed or painful.

● Neurological Issues: Difficulties are found in the nerves controlling eyelid movement.

● Diseases that occur all over the body: These can involve dehydration, high fever, or poisoning.

The cause needs to be discovered and treated quickly by visiting the veterinarian.

FAQs About Cats' Eyelids

1. Do Cats Have Multiple Eyelids?

All cats have three eyelids: a top eyelid, the cat's second eyelid, a bottom eyelid, and another called the nictitating membrane. That, however, is not how it works for humans who have two from birth.

2. How many eyelids does a cat have: one, two, or three?

Though your cat's eyes are protected by two normal eyelids, a third attached membrane also plays a role. The structure is sometimes believed to be the cat second eyelid, while in truth, it is a different second eyelid.

3. What Is This Extra Coating in a Cat's Eye?

You can see the nictitating membrane cat at the inner corner of its eye. It's a thin, transparent eyelid. The cat inner eyelid slants along the eye's edge to keep and remove anything that may impact the surface without completely shutting the eye.

4. What is the Importance of Two Eyelids?

Like humans, cats use their extra eyelids to serve important functions, including protection and lubrication.

How to Care for Your Cat's Eyes and Keep the Third Eyelid Healthy

By taking care of your cat's eyes you will help it feel better and maintain good sight. Try these tips and buy these products to maintain your feline's eye health and control irritation.

1. Keep Their Eyes Clean

If the irritation causes the third eyelid to become visible, dirt, dust, and discharge may collect around your pet's eyes. Caring for your pet's eyes is easier with wipes designed just for pets. Grooming wipes are safe to use and will not cause any trouble when you clean your cat’s eyes.

2. Provide a Stress-Free Environment

If you are stressed or feeling unwell, your third eyelid may become easier to see. Give your cat a safe and clean place to rest. WOPet's cat toys range includes items that are designed to ease your cat's anxiety and stimulate their mind.

3. Monitor for Signs of Eye Problems

Redness, swelling of the eye, or watering is something to always pay attention to. The sooner it is diagnosed, the easier it is to treat. In case you notice any symptoms of warning, take your pet to your vet immediately.

4. Nutrition and Overall Health

Your cat’s eyes and immune system is strengthened by taking care of what you feed it. There are a variety of quality pet foods and supplements you can find out with research that can help keep your cat healthy. You can also use an automatic feeder to schedule feeding times, making life easier for those with busy schedules.

Interesting Facts About the Third Eyelid And Vision

● The third eyelid provides moisture to a cat's eyes, something needed during hunting, which often means fast head movements and exposure to different conditions.

● One reason why cats handle both dust and wind better than other pets is this trait.

● The nictitating membrane cat part helps them as they search for food during their lives.

Final Thoughts

Despite the small size and general obscurity of the cat’s third eyelid, it is excellent proof of cats' evolution, acting to protect, clean and guard a cat's eyes. Learning about the purpose of a cat's third eyelid and looking after it allows your cat to keep seeing comfortably for much longer.

To buy products that will benefit the health of your dog or cat, like wipes and toys, visit WOPet as their offerings can help you to take care of your pet.

Placing pet-friendly wipes around your home and giving them safe toys will help keep your cat's eyes healthy and comfortable. With the help of good care, your cat can be cheerful, healthy and with clear eyes.