Have you recently noticed white spots on your guinea pig's fleece liners and wondered why? Well, these mysterious white spots can indicate that your guinea pig has eaten a lot of calcium. The white spots in themselves shouldn’t cause you alarm; they’re just how your piggy naturally passes unwanted calcium through their urine. You’ll usually see white marks a day after a heavy calcium meal.
While calcium is an essential mineral in your guinea pig's diet, an overload of it can be harmful to their health. However, it’s also crucial to be aware that it should never be removed entirely, as a lack of calcium in your guinea pig's diet could also be detrimental. Confusing, isn’t it! Here’s our easy-to-follow guide to guinea pigs and calcium, with helpful comments from Tara Richardson, who runs the Kavee Rescue.
What exactly is Calcium?
Calcium is a mineral which is essential for most animals, including humans and guinea pigs. It’s needed for several vital bodily functions such as regulating muscle contractions and heartbeat, and ensuring normal blood clotting.
Calcium also helps strengthen bones and teeth - and we all know just how important guinea pigs’ teeth are for their survival. After all, a piggy’s teeth never stop growing and they need them for munching yummy hay and fresh veggies!
What are the main sources of calcium for guinea pigs?
Calcium is in several different types of foods. You may be aware that, for us humans, dairy produce like milk and cheese are excellent sources of calcium. But how about guinea pigs who obviously CANNOT be fed dairy snacks such as cheddar or brie? Thankfully, calcium can also be found in raw leafy greens and vegetables that guinea pigs love to eat.
Some calcium rich foods include:
- Kale
- Spinach
- Dill
- Parsley
- Beetroot (particularly their leaves/greens)
- Oranges
For a comprehensive list of high and low-calcium vegetables, please check the very useful list provided by Guinea Lynx.
How much Calcium do guinea pigs absorb?
Guinea pigs absorb about 50% of the calcium they ingest. Just like hoomans, vitamin D aids in the absorption of calcium, so try to give your guinea pig about 20 minutes of daily sunlight as long as it’s not too cold. Other minerals are critical to the absorption of calcium, such as phosphorus.
How does calcium work in your guinea pig’s body?
Calcium is stored in the teeth and bones, and is also found in the cells and blood. Your guinea pig’s body cleverly controls exactly where the calcium travels to keep everything healthy, with a process known as calcium homeostasis.
Homeostasis is the technical term used to describe balance, which is what exactly happens within your guinea pig's cells. To achieve a nutritional balance, this process involves two hormones called parathyroid hormone (PTH) and calcitonin, along with vitamin D and another mineral called phosphorus as well as small amounts of the minerals, magnesium and potassium. Together, they all control how and where calcium is stored within the body.
Phosphorus is especially important in this process as it works together with calcium as a team to build healthy bones. When calcium levels rise, phosphorus levels fall - and vice versa. That's why it's important to have the right balance of both these crucial minerals in order to keep the body running smoothly. This can be achieved by providing your guinea pigs with a balanced diet!
What are normal levels for calcium and phosphorus in guinea pigs?
As stated before, phosphorus is important for the absorption of calcium, so really we should be looking at both of them instead of just calcium levels. A healthy guinea pig’s calcium level should be between 2-3 mmol/L of blood and their phosphorus level should be in the range of 0.68 - 2.3 mmol/L per litre of blood.
This really isn’t something you can check at home. Your guinea pig’s calcium and phosphorus levels must be tested by a qualified vet. If you are currently searching for a vet for your guinea pigs, please consult our map of recommended cavy savvy UK vets.
However, your guinea pigs' calcium and phosphorus levels are not something you should worry about, unless you know for sure your guinea pigs are prone to calcium excess, in which case you should watch their intake.
When should I worry about calcium for my guinea pigs? And what are those white spots on my guinea pig’s fleece liner?
Guinea pigs expel excess calcium in their urine. These milky white calcium secretions are what you may see on your guinea pig's fleece liner or pee pad.
Tara explains: “White powdery spots on your piggy’s fleece are nothing to be concerned about. Guinea pigs naturally pass unwanted calcium through the urine and so you will see white marks a day after a heavy calcium meal. The concern is when there is sludge, a gritty texture or blood.”
However, harder, grittier white stains on your guinea’s pig bedding may indicate a health issue. Why? Well, as guinea pigs’ urine is naturally alkaline, calcium can’t dissolve in it. Instead, it tends to form clumps otherwise known as uroliths or ‘urinary tract stones’. These hard stones can develop anywhere in your guinea pig’s urinary tract, bladder or kidneys and are more commonly found in sows.
These stones are sometimes tiny enough to pass when your piggy pees. However, larger stones may get stuck in the urethra or cause bladder irritation, bleeding or even prevent your guinea pig from urinating at all. Common signs to watch out for include hard, gritty white stains on your guinea pig's bedding or noticing them straining, squeaking or crying as they try to pee.
On the other hand, calcium deficiency can lead to weak bones and teeth, which can be devastating for your piggy’s health.
How can guinea pigs be treated for bladder and kidney stones?
Treatment for bladder stones can be risky, which is why it’s important to be aware of what you’re feeding your piggy in order to avoid this painful health issues in the first place.
Tara explains: “Treatment of stones will depend on your exotic pet vet. Many are managed with a low calcium diet and pain management. Antibiotics can be given in the event of stones causing an infection along with anti inflammatory medications and painkillers. Some piggies can pass the stones if they’re small enough. If not, surgery can be performed. As we all know, surgery brings its own risks but if the stones are severe and too large to be passed through the urethra this may be the only option. We recently lost a little boar to complications after treating bladder stones.”
Why are Kavee fleece liners and pee pads useful for keeping an eye on your guinea pig’s calcium levels?
We’ve already talked about the white stains secreted by guinea pigs in their urine, indicating that their diet is too high in calcium. When these stains are harder and grittier, it may be a sign that things aren’t quite right with your piggy.
Now consider this: you’re unlikely to spot the tell tale white marks if your guinea pig is peeing onto wood shavings or white paper bedding, are you? However, if your piggy’s cage is lined in soft fleece liners and pee pads, it will be easier to spot suspicious white stains on the fabric and adjust your piggy’s diet as required.
Should I be worried about feeding high-calcium food to my guinea pigs?
If your guinea pigs are healthy, there is nothing to worry about. Just know which food are rich in calcium and only feed them two to three times a week (For a comprehensive list of high and low-calcium vegetables, please check the very useful lists provided by the Guinea Pig Forum as well as Guinea Lynx).
Tara explains: “How often should you feed calcium rich foods? Well, the simple answer is that, as long as you're balancing the diet, it’s not something to worry about too much. Feeding high calcium foods two to three times a week is usually adequate to allow for a good variety of foods throughout the week. Keep a close eye on your piggy’s wee and poo - it’s often one of the first signs that something is wrong. Always consult an exotic vet if you're worried, feed a balanced, varied diet and give them the happiest life you can.”
My guinea pigs have had an issue with calcium, what should I feed them now?
If your guineas are displaying signs of having too much calcium in their diets, limit the high calcium foods to just once or twice a week. Owners of guinea pigs with bladder issues or similar health concerns, in particular, may also want to consider "low calcium diets" where they keep an eye on the Calcium:Phosphorus ratio. As explained earlier, it is important to also consider phosphorus when keeping an eye on calcium since those two work together.
All in all, the ratio Calcium:Phosphorus should be around 1.5:1. You do not need to get the ratio perfect - as long as it is somewhere within the range of 1.3:1 to 1.6:1, and you are feeding a good variety in moderation.
To calculate the ratio in your piggies' vegetables and fruits, you can try this free Calcium:Phosphorus ratio calculator by Guinea Lynx. Always aim for a ratio between 1.3:1 to 1.6:1.
Also take into account the calcium and phosphorus content in your guinea pig’s pellets. By consulting the nutritional analysis section on the packaging, you can also figure out their ratio (usually they are given as a percentage). Some pellets are made with Lucerne, which is Alfalfa hay, and rich in calcium. Whilst piggies find it very tasty, it should be fed in moderation to adults. Instead, look for foods made with Timothy hay, which is lower in calcium.
It’s important to be aware that baby guinea pigs need more calcium than older piggies as their bones are still developing. For that reason, feed calcium-rich Alfalfa hay to little ones to ensure they’re getting enough. The same applies to pregnant and nursing mums. However, once your piggy is fully grown, switch to Timothy hay which is lower in calcium but high in fibre.
Please find below four examples of calcium-balanced meals for two guinea pigs with a ratio between 1.3:1 to 1.6:1.
Reminder of some golden rules for feeding your guinea pig:
- Your guinea pig should have an eighth of a cup (16g) of pellets per day.
- The rest of their food should be made up of fresh food and hay.
- Feed your piggy 1/2 to 1 cup of fresh leafy greens or other vitamin C rich vegetables daily (approximately 50g per guinea pig).
- Guinea pigs require 10 to 30 mg/kg of vitamin C daily to prevent scurvy
- Only give fruit as an occasional treat, once or twice a week.
- Your piggy should have constant access to fresh water.
- Be careful to only feed your guinea pig calcium-rich veggies such as kale or spinach two to three times a week only
- As spinach leaves often come in mixed salad bags, save a few of the leaves for your guinea pig but only serve them once or twice a week as a treat.
Conclusion
Calcium is an important part of your guinea pig's diet for healthy bones and teeth. If calcium rich foods are fed too frequently, guinea pigs have an increased risk of developing urinary tract stones. However, as long as you feed your guinea pigs a balance diet, by following the tips outlined above, don't sweat it unless you notice an issue! Should your guinea pig show signs of a high calcium diet, such as gritty or sludgy white urine, it is advised to consult a cavy savvy vet to further assess your guinea pigs calcium and phosphorus levels.
