We all like to give our pets variety and treats as part of their diet. So today, we’re going to look at what rabbits can’t eat. Understanding this is just as important as knowing what a healthy rabbit diet should look like.
This article will discuss unhealthy rabbit diets, foods to feed with caution, and those that would make it onto any self-respecting list of forbidden foods for bunnies. We’ll also consider nutrients that are essential but can cause problems if too much is given.
Four Dietary Trends – Avoid These And You Are Halfway There
1. Feeding Muesli Type Rabbit Foods
As well as the critical hay portion of their diet, there are two main kinds of food sold for rabbits – pellets and muesli. The muesli is not desirable for several reasons. Firstly, it allows the rabbit to selectively feed, and this can lead to obesity and malnutrition (lack of nutrition caused by not eating the broad selection of nutrients needed).
Rabbits have evolved to select plants with higher energy value when grazing (usually young, tender shoots). This means that they will tend towards selecting the higher calorie ingredients in a muesli mix.
Secondly, most muesli mixes are based on grains, legumes, and seeds. None of these would form part of a natural rabbit diet. They are high energy elements that will often be favored by rabbits over hay pellets and hay, causing obesity, digestive issues, and nutrient imbalances.
Thirdly, legumes, grains, and seeds can also contain high levels of antinutrients like phytates and lectin, which can affect the absorption of essential minerals in a rabbit’s gut by binding to these elements. More on this soon.
So, considering all these points, we can see that muesli mixes are one of the rabbit foods to avoid.
2. Feeding Too Much Protein To Your Rabbits
Rabbits are grazers, adapted to primarily eat the leaves, stems, and even flowers of grasses and wild meadow plants. These plants are not high in protein, and a rabbit’s protein needs are low (around 12-14% of the diet).
Legumes and seeds have a high protein content, and selective feeding can boost the effect of this even more. Even alfalfa hay – a legume grass – has a higher protein content than standard grass hay.
It’s easy to see how a pet rabbit could be eating significantly more protein than they need. Excess protein is processed in the body and stored as fat. The breakdown products of protein can put a strain on the rabbit’s kidneys as they age.
So, while protein is clearly not toxic to rabbits, it is likely to cause problems if too much is included in the diet.
3. Feeding Too Many Calories To Your Bunnies
Calories are simply the amount of energy a food contains. If a rabbit takes in more energy than they use up, they will gain weight over time. Even a small excess can lead to obesity if it continues long enough.
All food contains calories, with fats being the most concentrated form of energy in food. Your bunnies have a really low requirement for fat – less than 2% of the diet – and food items such as legumes, seeds, and even some fruits can contain far more than is actually needed.
However, excess protein and carbohydrate – especially processed carbohydrate, like bread – is readily converted by your rabbit into fat. So, feeding treats other than fresh vegetables can also lead to weight gain.
This even applies to fruit. Wild rabbits do include a small number of berries (in season) in their diet when they can but do not generally eat much fruit. Berries contain less sugar than most fruit, so if you are sure that you want to feed fruit to your rabbits, it is best to choose a variety of berries in treat amounts.
Shop bought treats can often be quite unsuitable for a rabbit and are really not necessary. Avoid those based on grains, legumes, and seeds or those that contain over 2% fat. High fat treats are definitely a rabbit food to avoid.
4. Feeding Rabbit Pellets Adlib
Rabbits need food to be available all of the time. However, this should only be hay or fresh grass (grazing) rather than rabbit pellets. Standard grass hay (meadow hay) contains plenty of long fiber, which helps to maintain digestive health and is low in fat.
If you feed rabbit food (pellets) adlib, it can often lead to many more calories and higher protein intake than is needed, again resulting in obesity. It can also mean digestion suffers as hay intake is decreased or nonexistent.
Pellets should be fed in a measured amount and can be up to about 10% of the diet, but they’re not a necessity unless your rabbit struggles to maintain weight. However, most bunnies love them – so a small scattered portion is a great foraging addition.
Remember, keeping your bunnies safe is not just about the foods that rabbits can’t eat – it’s also about how we feed the foods that we know are healthy and safe.
Antinutrients – What Are They And Why They Matter?
Many plants naturally contain compounds and chemicals that can interfere with the absorption of the nutrients in the gut. These plant chemicals are called antinutrients because they can stop your rabbits (and you!) from getting the nutrition they need.
There are several common antinutrients with different ill effects. Some of them (like fiber) also have important beneficial effects on the digestive process or (like lectin) as a powerful antioxidant.
Your rabbits need a high fiber diet to keep their gut healthy. That same fiber also prevents the absorption of some of the protein and minerals in the food. To balance this, they must be fed a mineral-rich diet that meets their needs.
All hay, greens, herbs, vegetables, grains, legumes, and seeds contain some antinutrients because, at the very least, they contain fiber. However, hay, greens, and herbs, in particular, are also generally rich in minerals.
Some of the other commonly occurring antinutrients that may affect your rabbit’s diet include:
- Amines and nitrates– nitrates and/or amines are found widely in fruit and vegetables. They can combine in the gut to create nitrosamines that are thought to be carcinogenic. However, this effect may be canceled out by the antioxidants they contain.
- Oxalates (oxalic acid) – this naturally occurring plant acid can bind with minerals (like calcium and iron), which means there are fewer minerals for your bunny to absorb into their body. The result is the formations of crystals, some of which are passed out in the feces, but some may also contribute to bladder and kidney stone formation, which is common in rabbits. Many vegetables and some fruits are high in oxalic acid, including spinach, beets/beet greens, chard, parsley, celery, and strawberries. However, these foods are still considered healthy and okay to feed to your rabbit in moderation.
- Glucosinolates are plant chemicals that are found particularly in cruciferous vegetables, such as broccoli, cabbage, cauliflower, and sprouts. They help the plant to fight off diseases and have been shown to have a protective effect against cancer. However, when eaten in excess, they cause thyroid and reproductive issues in rabbits. In this instance, “excess” is defined as being the primary food source, so everything in moderation.
The presence of these plant chemicals does not mean that the foods that contain them are toxic to rabbits – just that they can cause problems when overfed. By feeding a variety of plants, you can avoid these issues as you’re not relying too much on a single food source.
However, some plant chemicals are toxic to feed to your bunnies, and we need to avoid plants where the level of these toxins is high. Some of these are listed in the Foods Your Rabbit Can’t Eat section below.
Unnecessary Food Additives That Can Affect Your Rabbits
Rabbits can get all of the sodium and chloride they need from an excellent diet, so it is unnecessary, but not thought to be harmful to give your rabbit a salt/mineral lick. It’s one of those grey areas where there isn’t much agreement between experienced owners.
What most people would agree on is that giving table salt is unnecessary and not good for a rabbit’s health. Salt licks are actually mineral blocks that contain a spread of minerals – not just sodium and chloride.
Some muesli type rabbit foods and treats contain artificial colors, which are generally used in pet food to make it look more appealing to human eyes. The most common artificial colors used are:
- Yellows 102, 104, 107, 110
- Red 122 through to 129
- Blues 131, 132, 133
- Green 142
- Black 151, 153
- Browns 154, 155
These dyes are a completely unnecessary addition to your rabbits’ diets. In sensitive individuals, it can cause problems with the skin, gut, respiratory tract, and the central nervous system.
In small amounts, artificially colored food may not be toxic to rabbits as such. Still, because of the potential issues, highly colored mixes are rabbit foods to avoid.
Some Groups Of Foods To Feed To Rabbits With Caution
Food That Doesn’t Contain Much Nutrition
These are foods that generally won’t harm your rabbit, but they are also relatively low in micronutrients. They would include food like pale leaf lettuce, for which there are many more nutritious alternatives such as arugula and greens. Also, cucumber, which is about 98% water – better alternatives are broccoli, green pepper, or squash.
Dried Foods That Concentrate Nutrients
Some rabbit owners like to dehydrate fruit and vegetables to create bunny treats. Dehydrating a food concentrates the nutrients by removing most of the water. In the case of fruit, one of these nutrients is sugar.
It should be noted that a small piece of dried fruit has much more sugar in it than a piece of fresh fruit the same size. Giving your rabbit a single berry on occasion is a healthy treat. Because dehydrated fruit is so much smaller, it’s tempting to give several berries to make a good treat portion. This means that sugar intake can soon add up.
If you are keen to dehydrate food, you need to get a good handle on portion size – thinking in terms of the fruit when it’s in its natural state. Or simply dehydrate vegetables instead. Because of their lower sugar content, they pose much less of a problem.
High Calcium Foods
Calcium is another nutrient essential for your rabbit but can be a problem if the diet contains too much. Many mammals do not absorb excess calcium from their food, taking only what they need.
Rabbits, however, have a somewhat different digestive system and generally absorb all of the available calcium. Although the current research isn’t conclusive, most vets encourage a lower calcium diet for any rabbit with high blood calcium, kidney disease, or bladder stones.
Alfalfa hay is high in calcium, as are some greens like broccoli leaves, kale, and collard greens. Lower calcium alternatives include mixed grass hay, broccoli heads and stem, cilantro, dark leaf lettuce, watercress, and endive.
And Finally – The Foods Your Rabbits Can’t Eat
There are a few foods that rabbits must not eat because they can cause problems with digestion and health. Some are toxic to rabbits, while others are known to cause health issues. Some big groups of foods are (hopefully) obvious – no animal products, no fried or fatty food, and nothing highly processed or sugary.
Wild plants that are toxic to rabbits
Some wild plants are toxic to rabbits – this delightful poem details some of the common ones.
Feeding Ode for Rabbits
By G. Lodham
Do not give a Rabbit yew,
Spurge, Fool’s parsley, feverfew.
Nightshade, purple-flowered or white,
Lords and Ladies, Aconite.
Bryony with berries red,
Pimpernels should not be fed.
Add Laburnum, Golden rain,
Hemlock with its Crimson stain.
Buttercup and celandine,
Foxglove, poppy, and woodbine.
If they eat these, rabbits die,
Caution says, ‘Don’t let them try.’
Pride Veterinary Centre has published a neat PDF that lists toxic and safe common plants for rabbits.
Bulbs, including onions and garlic – seem to have been linked to immune suppression and anaphylaxis in rabbits.
Yogurt drops and sugary treats like cookies – may lead to enterotoxemia, an overgrowth of bad bacteria in the rabbit’s digestive system.
Unsafe Fruit and Vegetables
They contain a tiny amount of a substance that is converted to cyanide once ingested. They would have to eat a lot of seeds for this to be a real threat, but some vets recommend that you avoid feeding them to be on the safe side.
Rabbits seem to be particularly sensitive to persin – the plant chemical that makes avocado toxic to several species of pets. All of the fruit (flesh, stone, and skin) contains persin, but it is more concentrated in the skin and stone.
Garlic, onions, chives, and shallots
Onions and related bulbs contain sulfur compounds, that when chewed, undergo a chemical change into disulfides, which can cause red blood cells to rupture, leading to anemia. Many mammals have issues with eating onions and garlic.
Potato and potato tops
Potato greens contain large amounts of solanine – the plant chemical that makes green potatoes toxic to humans. This is toxic to rabbits. Potatoes themselves are also problematic as they are full of starch, which the rabbit’s digestion hasn’t evolved to process properly.
Rhubarb, including the leaves
Because of the high level of oxalic acid in rhubarb, particularly the leaves, it should not be fed to rabbits. This is because of their predisposition to bladder and kidney stones and the link between oxalates and these conditions.
Like potatoes, tomato plants have high solanine content, which is toxic to rabbits.
Rabbits love to eat! Indeed they have evolved to spend by far the majority of their waking time grazing and foraging. Even so, their digestion is specifically adapted to eating long fiber in the form of wild grasses and meadow plants.
Because of this, their healthy diet is limited, and there are many food items they shouldn’t eat. We hope you now feel informed about the foods your bunny can’t eat, and why these foods could harm your precious pet.