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About Lethal Whites

Microphthlamia or better known as the lethal white gene is caused by breeding a roan x roan or dalmatian x dalmatian or a dalmatian x roan together.

Studies show that there is a 25% chance of guinea pigs born from the breeding of a roan x roan or dalmatian x dalmatian or dalmatian x roan. That's one in four chances it will result in having a lethal white baby. Usually they don't survive birth, past a week or fight and survive. There are responsible breeders will never intentionally breed these dalmatians and roan's. Usually this is avoided when breeding a solid colour with a roan or dalmatian. Such as a self black, which is a guinea pig that is completely black in colour. 

Signs of a lethal white is they are born dead, die soon after birth or have a shorter life. Lethal white guinea pigs are always born completely white with red-bluish eyes. This is not just a colour, it's because this is due being born without skin pigmentation. They are born blind in one or both eyes, they can be born with no eyes. Born deaf in one or both ears. They usually have teeth deformities or teeth missing or no teeth. If they have teeth this usually means they will require ongoing dental treatment to keep there teeth filed as there teeth grow faster then a normal guinea pig. If they have no teeth, they require crittacare feeds to give them the vitamins and minerals they require. They also require there food to be minced/ ground down. They can sometimes be born with head tilt or slowly develop it as they grow. 

A lethal white guinea pig does not have a life expectancy as they are born with a weaker immune system and have on going issues. They can live a good life if treated correctly, they do require ongoing care and vet treatment in order to make sure they are healthy and and can live a happy life. 

Lethal Whites: About

What is the difference between a Pink Eyed White and a Lethal White? Are all Pink Eyed White guinea pig's Lethal Whites?

This question gets asked quite often, so what better way to help then answer with some more information. With the help of photos of Vanilla and Mello and the difference between them.

Lethal Whites: About


Vanilla is a Pink Eyed White.
You can tell this by the following:
- The way his body sits, shows he has a healthy body and immune system.
- His eye's are wide and bright.
- His eye's are bright ruby red.
- He's head sits straight and he looks directly at you.
- He is alert of all the noises and movement around him.
- He has darkening in his ears.
- Has all of his front teeth.



Mello is a Lethal White.
You can tell this by the following:
- She sits differently, showing that her body and immune system isn't the best.
- Eye's sit differently, while one eye may be big the other is smaller. Eye's are usually smaller and more sunken.
- Eye's are dull, redish blue in colour.
- Her head sits on an angle, cause of head tilt from neurological issues. Neurological issues can also cause twitching in the eyes and seizures.
- She is not always alert of things around her, as her hearing and sight is not as good as Vanilla. She is always more cautious because of this.
- Gets overwhelmed easier and spins in circles.
- Smells overwhelm her, as she relies more on smell.
- Ears are a brighter pink.
- She only has three front teeth, they grow at a faster rate to Vanilla. Require regular checks and teeth trims.

Lethal Whites: Team

There is always a way to tell the difference between a Pink Eyed White and Lethal White. As there are strong differences. Not all Pink Eyed White guinea pig's are Lethal White. All non Lethal White guinea pig's can live long and healthy lives. While a Lethal White's life span can be unpredictable, because of there condition.
A Lethal White is born from breeding a roan x roan, dalmatian x dalmatian or a roan x dalmatian. Although there is a 25% chance of a Lethal White being born. That is still 1 in 4 chances. It is not impossible for more then one Lethal White to be born in a litter. It has happened a few times now.

Lethal Whites: Text

Closer Look At Lethal Whites Compared To Pink Eyed Guinea Pigs

Let's take a closer look at what makes a lethal white different to a pink eyed guinea pig. We will explore there differences in there eyes, teeth and head tilt.


Lethal White Eyes

As you can see with the difference with a lethal whites are as follows: 
- Eye shape is different. 
- Eyes tend to be smaller in size. 
- Eyes are a reddish blue in colour. 
- Eyes are dull and slow to respond.
- Eyes has haze/ fog look to them.
- Eyes are sunken into skull.


Pink Eyed Eyes

As you can see the difference with pink eyes are as follows: 
- Eye shape is wide and regular. 
- Eyes are bright ruby red in colour.
- Eyes are alert and open. 
- Respond to anyone or anything that gets close to them. 
- Sensitive to the sun or bright lights. 
- Eyes sit correctly in the skull. 


Lethal White Teeth

As you can see with the difference lethal whites teeth are as follows:
- Teeth can be missing. 
- V shape in teeth. 
- Teeth are uneven/ don't sit straight. 
- Teeth grow at a faster rate and need to be monitored and trimmed regularly to prevent overgrowth.


 Regular Guinea Pig Teeth

As you can see the difference with a regular guinea pigs teeth is as follows: 
- All teeth are present. 
- Teeth are straight. 
- Teeth growth is a normal rate. 
- Teeth should not require trimming if given a correct diet of regular hay etc. 


Head Tilt

Head tilt is very easy to spot. This is when a guinea pig has their head tilted to the side. Although this is common in lethal whites this can occur for regular guinea pig's. 
What causes head tilt? 
Head tilt is caused when a guinea pig either develops or is born with neurological issues. 
What are neurological issues? 
Neurological issues are caused by damage to the proprioceptive pathways of the spinal cord, cerebellum or vestibular system. 
What are the signs? 

In-coordination of voluntary movements of the limbs, body and/or head and neck. This is what leads to head tilt, seizures, muscle spasms and even walking in a circle. 

Lethal Whites: Team
Lethal Whites: Team



Houdini is a perfect example of a roan, a roan is a breed that has white flicks throughout a solid colouring of the fur. 
This however can become even harder to tell on a guinea pig with white fur. A guinea pig that has white fur and is a roan is what is known as a hidden roan. 



Chip is the perfect example of a dalmatian, a dalmatian is a breed that is white is black spots/ markings throughout its fur. Basically the same when you think of a dalmatian dog.


How To Care For A Lethal White

Information gathered from experience of caring for lethal whites.

Caring for a lethal white does prove to be more work and time then a normal guinea pig. You must be prepared to be committed and have the time if you do plan to care for a lethal white. As there has been more breeding and lethal white's being born into the world and some people ending with them and not knowing what to do. I thought i would share some helpful hints. This in no way is encouraging to breed and make lethal whites. This information is to help those who need it. 

Considering lethal whites are born either blind, part blind or with no eyes. It is very important to keep there cage layout exactly the same. So they can easily get around and assess food and water without any issues. Usually lethal whites can be born deaf, partly or something be lucky enough to have there hearing in rare cases. So bare in mind when approaching a lethal white, they may be more startled then a normal guinea pig. As they have sight or hearing like a normal guinea pig. They rely strongly on scent, so you will see a lethal white with there nose in the air quite a bit to get a sense of whats around them. I usually put my hand in front of there nose and let them sniff it first. Then approach them, this way it allows them to know you are there first. 
The next important thing to know about a lethal white is there teeth. All normal guinea pigs have 20 teeth. Firstly lets talk front teeth, better known as incisors. Usually normal guinea pigs are born with two upper and two lower incisors. Meaning they have four front teeth altogether. Lethal whites can be born with all there front teeth, teeth missing or no teeth at all. If they have four to three front teeth they can eat normally. But will still require a vitamin rich and calcium diet. I give my lethal whites that have four to three teeth, a good variety of veggies and crittacare daily as a boost for them. As lethal whites have weak immune systems, weaker bones and there teeth grow much faster then a normal guinea pig. This means they will require there front teeth to be trimmed every two to four weeks as they tend to overgrow and make it harder for them to eat. If they have two front teeth or one front tooth. They can still eat okay, but require there food to be prepared differently and they can struggle to eat food normally due to lack of teeth. I cut up vegetables finer and in smaller pieces so its easier to pick up and eat. As for chaff and pellets, i put them through a blender and grind them down to a finer blend. So once again its easier for them pick it up and eat. I give my lethal whites with two teeth or one tooth a good variety of veggies and crittacare daily as a boost for them. Even with less teeth there teeth still grow much faster then a normal guinea pig and will require there front teeth to be trimmed every two to four weeks as they tend to overgrow and make it harder for them to be able to eat. If they have no front teeth, this is where it requires more time and patience. So they have no front teeth, they struggle to have anything to use to be able to pick up food to eat. So pellets have to be softened down into mush, crittacare feeds must be at least two times a day and vegetables must be blended to a mush as well. Since they have no front teeth, they will not require them to be trimmed regularly. 
Now, lets talk back teeth. Better known as molars. Normally guinea pigs have a pair of upper and lower premolars and three pairs of upper and lower molars. 
As stated lethal whites teeth grow faster then normal guinea pigs. So back teeth checks are a must, the best way to have this done is by a vet. Regular vet checks for back teeth and health checks are a must with lethal whites. 
One of the most important things to know about a lethal white is there health and how to keep it as healthy as it can be for a lethal white. As a lethal white struggles to keep there body temperature and can easily get sick. It is important to make sure they are always kept inside only. Where they can have heat when it is cold or cold when it is hot. Lethal whites can not cope with wood shavings or hay as bedding as they have weaker lungs and struggle with too much dust. This doesnt not mean they shouldnt have hay. I put hay in a corner of the cage, in the same spot everytime. So it can always be located. I find toggle mats vet bed or fleece is the best option of bedding for there cage. 
Lethal whites are also prone head tilt/ neurological. They can be born with it, develop it as they age or be can lucky enough to never develop it. Lethal whites must be kept in a calm environment at all times, to reduce any chances of stress. Lethal whites must be weighed regularly to keep an eye on there weight, as lethal whites struggle to keep weight more then a normal guinea pig. Any signing in weight drop could mean a lethal white is sick or something is wrong. In this situation it should be assessed by a vet as soon as possible. Lethal whites can go downhill extremely fast, as there immune system is weak. They can not fight a sickness as long as a normal guinea pig can.

Lethal Whites: About

Research/ Information Gained

Lethal White's have a weaker immune system. Making it important to make sure there cage is regularly cleaned and on a proper diet that contains plenty of vitamins and minerals. They are more prone to getting overwhelmed and having seizures. Seizures can come on at any moment. Sometimes you can bring a lethal white out of a seizure and sometimes you can't. It's important to be with them. Hold them wrapped in a blanket or towel with a heat pack underneath. Followed with massaging them, to keep there body stimulated.

Lethal Whites: About

Special Mention Piggies

Special piggies who's stories deserve a special mention.


Little Miss

Lethal white that didn't make it to the sanctuary.

Little Miss was a lethal white. Although she didn't make it to make it to the sanctuary. Her story still deserves to be shared. A friend of mine noticed a litter of dalmatian guinea pig's for sale. She went to go and get one of the female's. Once she got there and spoke to the person and explained about lethal whites. The person was unaware. But was soon handing her a lethal white. My friend immediately contacted me and told me about her and what had happened. She was driving her to me, when sadly she had a fit and passed away. Little Miss was only 24 hours old, she had no eyes and teeth missing. Sadly so many people are unware of lethal whites and the risks.



Not a lethal white, but still a special piggy that deserves a mention.

Even though Gizmo was not a lethal white, his story still deserves a special mention. Gizmo was abandoned in a ladie's letterbox! Luckily he was found and she contacted me about him and i offered to take him on. Gizmo had many problems and deformities. He had a deformed spine, it was badly curved. Deformed mouth/ nose. I mean it hadn't even formed correctly.. Front teeth didn't sit correctly. Top front teeth were rotted. Jaw didn't sit correctly. Back teeth were clearly missing. Eyes were dried up beyond saving, so he was completely blind. There was probably more to discover, but sadly Gizmo's little body was not strong enough. Even though he had a strong spirit, he pssed away a few days later. Gizmo was the result of incorrect breeding. Even if a guinea pig with extreme deformities is bred into the world. It is not okay to dump a guinea pig that is baby in someone's letterbox!

Lethal Whites: Team
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