Estimated reading time: 7 minutes
Crested geckos eat fruit and insects in the wild. However, in captivity fruit should only be given in moderation as you can do a lot wrong as a beginner. Crested geckos need a good calcium-to-phosphorus ratio and sadly most fruits have a bad ratio. But what about apples?
Crested geckos can eat apples but only as an occasional treat. Apples have a bad calcium-to-phosphorus ratio but have a low oxalic acid level. Apples aren’t that popular as a fruit for crested geckos and – when given – should be put in a fruit mash with other more suitable fruit.
When you’re new to crested geckos, you want to give a commercial crested gecko diet supplemented with insects. It’s recommended to give fruit, including apples, only as a treat to your crested gecko. For more experienced users that know what they’re doing fruit can play a more important part in the diet.
In this article, you’ll learn a little bit about the nutritional value of apples and why they’re mostly suitable as a treat for your crested gecko and not as the foundation of a crested gecko diet. Finally, you’ll learn how to feed them to your crestie.
Nutritional Value of Apples
Apples are the edible fruit of apple trees and you can find apples almost anywhere in the world. They form a part of a healthy diet for us and are also given to certain animals as a treat. Apples can be eaten fresh, processed, or cooked.
The following nutritional data comes from FoodData Central:
|Total lipid (fat)||0.17||g|
|Carbohydrate, by difference||13.81||g|
|Fiber, total dietary||2.4||g|
|Sugars, total including NLEA||10.39||g|
|Vitamin C, total ascorbic acid||4.6||mg|
|Vitamin A, RAE||3||µg|
|Lutein + zeaxanthin||29||µg|
|Vitamin E (alpha-tocopherol)||0.18||mg|
|Vitamin D (D2 + D3)||0||µg|
|Vitamin K (phylloquinone)||2.2||µg|
|Fatty acids, total saturated||0.028||g|
Are Apples Good or Bad for Crested Geckos?
To determine whether apples are good or bad for crested geckos we need to take a look at two important nutrient levels:
- the calcium-to-phosphorus ratio (Ca:P ratio)
- the level of oxalic acid
Ca:P ratio of apples
Introduction to Ca:P ratio
Crested geckos need calcium to stay healthy and to prevent the development of a specific disease called metabolic bone disease. Gravid females, hatchlings and juveniles have a special need for calcium because they need the calcium to grow and to form eggshells (in the case of gravid females).
Calcium and phosphorus have a special relationship. When the calcium levels raise the phosphate levels are lowered and when the phosphate levels rise, the calcium levels drop. This means that, for crested geckos, foods should contain a lower amount of phosphorus than calcium.
A widely used tool to determine if a food is suitable for crested geckos is the calcium to phosphorus ratio. The Ca:P ratio can be described as a percentage but is more often described in terms of [number]:1 or 1:[number], where 1 is the mineral that’s the lowest of the two. To calculate the calcium to phosphorus ratio this way you’ll need to bring back the lowest number to 1. So, the ratio is calculated by dividing the largest number by the lowest number.
Research has shown that good calcium to phosphorus ratio (Ca:P) is between 1:1 and 2:1. For crested geckos, it’s recommended to have a calcium to phosphorus ratio of 2:1 or better.
Calculating the Ca:P ratio
So, the Ca:P ratio of apples is 1:1.8, which is considered a bad ratio. This doesn’t mean that apples are bad, but you should be aware that they aren’t that beneficial for crested geckos as for example papayas.
Oxalic acid in apples
Introduction to oxalic acids
Oxalic acid is a compound that’s found naturally in living organisms such as vegetables and fruits. It can be sometimes tasted in food when the amount of oxalic acid is very high. Textbook examples of plants that have a level of high oxalic acid are rhubarbs, star fruit, and spinach.
Oxalic acid is associated with the inhibition of calcium and the formation of kidney stones in humans. Crested geckos also need to avoid eating food that has a high level of oxalic acid. The compound will be bound with minerals such as magnesium and calcium and form oxalates (tiny rectangular crystals).
Since calcium is essential for crested geckos, it’s recommended to stay away from foods that have a medium level of oxalic acid and to avoid foods with a high level of oxalic acid altogether.
Oxalic acid level of apples
Peeled apples have a low level of oxalic acid and unpeeled apples have a medium level of oxalic acid. Since you always need to peel fruit before you give it to your crested gecko, we only take the peeled apple into consideration.
Apples are good as a treat
A crested gecko diet needs to have a good Ca:P and should be low in oxalic acid. Apples won’t give your crested gecko the necessary nutrients but can occasionally be given as a treat.
Feeding Apples to Crested Geckos
How many times to feed apples?
There are some gecko owners that give their own balanced diet consisting of insects and fruits to their crested geckos. However, there exist enough good commercial diets that offer all the nutrients needed.
If you’re a new crested gecko owner and don’t have experience with balancing the diet of a crested gecko, your crested gecko will benefit the most from a meal replacement powder that has a high nutritional value and add apples or even better a fruit mash as a treat once or twice a month.
How many apples can you feed?
If you make a mashed fruit puree you can fill a shallow dish with the same amount as a normal meal replacement powder. If you give fruit as a treat you can give a small piece of an apple and mash it up.
How to feed apples to crested geckos?
Crested geckos can’t bite hard so you need to be careful that the food you give can be eaten. Fruits are often mashed in a puree to make them edible. When you feed apples to your crested gecko you’ll need to do the same. You can also soften the apple by cooking it or by exposing the slices to air for a bit before giving them. This will soften them up.
Another way crested geckos can eat apples is by giving (almost) rotten apples. In nature, crested geckos will eat rotten fruit that has fallen on the ground because it’s much softer.
A step-by-step guide to feeding apples
Wash the apple
The peel of apples can contain a lot of bacteria and pesticides. You’ll need to wash the apple to make sure that your crested gecko doesn’t ingest bad bacteria or pesticides.
Peel and slice the apple
Peel off the hard skin of the apple and slice it in small pieces. Since crested geckos will only eat a small slice of the apple, you can eat the other slices yourself.
Mash it up in a fruit puree (optional)
You can feed the slice of apple to your crested gecko or mash it in a fruit puree with yogurt and other fruits like banana.
Fill a feeding cup with the apple slice or the fruit puree
You don’t want to overfeed your crested gecko. So, only give the same amount of food as a meal replacement powder. Your crestie will lick and bite in the slice or puree and will need little to no biting power.
Want to Learn More?
If you want to learn more about crested geckos as pets, please read the following articles.