Hedgehog night feeding: mealworms, calcium and weak back legs

Quick answer

A bowl left down all night is comfortable for the owner and expensive for the hedgehog. It removes the one measurement that tells you when something is wrong, and it lets a hedgehog eat by preference rather than by need.

Preference in this species means insects, and insects mean mealworms. A hedgehog that fills up on mealworms is eating a food that is high in fat and carries far more phosphorus than calcium, and the consequence over months is bone that gives way. The first thing owners notice is a hedgehog whose back legs are not working properly, which is also the first sign of an entirely different and untreatable disease.

Food goes down at dusk and comes back up in the morning. What is left in the bowl is the most useful health information you will get.

• Offer a measured portion at dusk and remove what is left in the morning. The leftovers are your early warning system.
• Mealworms are a treat, not a diet. Fed heavily they cause a calcium imbalance that weakens bone.
• Dust and gut load feeder insects. An insect fed on bran and eaten dry contributes almost no calcium.
• Weak back legs have several causes, and the treatable ones are only treatable if you go early.
• Never feed milk or dairy. Hedgehogs do not digest lactose and it causes diarrhoea.

Decide in 60 seconds

Why the always full bowl is the problem

The argument for free feeding is that a nocturnal animal eats through the night and should therefore have access all night. That part is correct. A hedgehog does eat in several bouts across its active period.

The mistake is leaving the bowl topped up rather than portioned. Two things go wrong.

You lose the signal.

A hedgehog that has gone off its food is telling you something important, and in a species that hides illness this is often the earliest thing you can detect. If the bowl is always full, there is nothing to notice. If a weighed portion goes down every night and one morning half of it is still there, you have a date and a number.

Intake drifts upward.

Hedgehogs in captivity have far less to do than hedgehogs in a field, and obesity is one of the most common problems in the species. Constant access to a palatable food is exactly the arrangement that produces it.

The practical version is simple. Weigh out the portion, put it down as the lights go off, and weigh what is left when you get up. Record both numbers. It takes under a minute and it turns feeding into monitoring.

Water stays available at all times. Portioning applies to food only.

What insect heavy feeding does to bone

Water available all night, food portioned. That combination is both better welfare and better information.

Bone is not inert. It is a calcium reserve that the body draws on continuously to keep blood calcium within a narrow range, because muscle and nerve function depend on it.

When the diet supplies too little calcium relative to phosphorus, the parathyroid glands respond by increasing the hormone that releases calcium from bone. Blood calcium stays normal, which is why an owner sees nothing wrong for a long time, and the skeleton pays for it.

Over months the bone becomes less dense. The early consequences are functional rather than dramatic: reluctance to walk far, a wider or lower stance, difficulty climbing onto the wheel, and a hedgehog that spends more time still. Later, ordinary activity is enough to fracture a bone.

Feeder insects sit exactly in this trap. Their bodies are protein and fat wrapped in chitin, and chitin is not a calcium source. Mealworms are the worst offender in common use because they are also the most palatable and the most heavily fed.

Two things change the arithmetic and both are worth doing.

Gut loading. Feeder insects fed on a calcium rich diet for a day or two before use carry that mineral in their gut. Insects kept in a bag of bran carry nothing.

Dusting. Coating insects in a calcium supplement immediately before feeding. Dust in a bag or a small container, use the insects straight away, and be aware that powder falls off within minutes, so dusted insects left in a bowl for hours are not dusted insects by the time they are eaten.

Which supplement, and whether it should include vitamin D3, is a conversation with a vet who sees hedgehogs, because over supplementation causes its own problems and the right product depends on the rest of the diet.

Weak back legs: the differentials

This is the single most important comparison in hedgehog medicine for owners, because the causes range from fully treatable to untreatable and they look similar at the start.

Nutritional bone disease.

Gradual onset over weeks to months. A hedgehog that is reluctant to walk, low to the ground, sometimes with a bowed or splayed appearance, often with a history of a mealworm heavy or insect heavy diet. Potentially improvable if caught before fractures occur.

Wobbly hedgehog syndrome.

A progressive degenerative disease of the nervous system. It usually starts with a wobble in the hind end, progresses to ataxia, then to an inability to stand, then to the front limbs, over months. There is no cure and management is supportive. It is often diagnosed by excluding the treatable causes, which is why going early matters.

Obesity.

A very overweight hedgehog moves poorly, cannot curl fully, and may be assumed to be weak when it is loaded.

Trauma and spinal injury.

Sudden onset. Falls, being trodden on, a limb caught in a wheel or a cage gap.

Arthritis and degenerative joint disease.

In older hedgehogs. Worse after rest, better with movement.

Tumours.

Common in this species. A mass pressing on the spine or in the abdomen produces hind limb weakness.

Foot and nail problems.

Overgrown nails curling into the pad, bumblefoot, or fibre wrapped around a toe. Always look at the feet, because this is the easiest cause to find and to fix.

Low blood sugar or systemic illness.

Weakness affecting the whole animal rather than the back end specifically.

Any hind limb change is a same day or next day appointment. The examination, and often imaging and blood work, is what separates these, and the treatable ones become untreatable if left.

Building the overnight bowl properly

The base of the diet is a measured amount of a suitable dry food. Many keepers use a high protein, moderate fat dry cat food, and there are also commercial hedgehog diets of variable quality. Read the analysis rather than the marketing, and choose with a vet if you are unsure.

Insects are a supplement and a training currency, not a staple. Vary them rather than relying on mealworms. Dubia roaches, crickets, black soldier fly larvae and silkworms all have different profiles, and rotating them gives a broader intake. Waxworms are very fatty and belong in the occasional treat category.

Small amounts of cooked plain meat, cooked egg and certain vegetables are used by many keepers as variety. Keep them small, keep them plain, and introduce them one at a time so that a reaction can be attributed.

Fresh water in a heavy shallow dish, available all night.

Things to leave out entirely: milk, cheese, yoghurt and any dairy, since hedgehogs do not digest lactose and it causes diarrhoea. Grapes, raisins, avocado, onion, chocolate and anything with added sugar or salt. Raw meat, because of the bacterial risk in an animal that will be handled. Hard nuts and seeds, which lodge across the roof of the mouth and behind the teeth and cause a hedgehog to paw frantically at its face.

Sticky and gluey foods are a practical hazard too, since they cling to the quills and the face.

Weight, condition and the numbers to keep

A hedgehog that settles to eat and then goes to the wheel is doing what it should. A hedgehog that goes straight back to bed is not.

Weigh weekly, on a kitchen scale, on the same day. Record it.

Look at the shape from above. A hedgehog in good condition is a teardrop, wider at the hips and narrowing to the nose. An overweight hedgehog is round, with visible fat pads bulging under the front legs when it tries to curl, and it cannot form a complete ball. An underweight hedgehog shows hip bones and a hollow behind the shoulders.

Record the portion offered and the portion left. The change in leftovers is more sensitive than the weight, because it moves first.

Note wheel activity. Many hedgehogs run considerable distances overnight, and a drop in wheel use is a reliable indicator of pain, illness or a room that is too cold.

Watch the droppings. Normal is firm and dark. Green, loose or mucousy droppings follow diet changes, but they also follow infection, and a change that lasts more than a day or two needs a vet.

Changing a mealworm dependent hedgehog

Abrupt withdrawal is the common mistake, and it produces a hedgehog that eats nothing. In a species prone to fatty liver disease, a hedgehog that stops eating is a genuine emergency rather than a temporary standoff.

The approach that works is gradual. Reduce the number of insects slowly over weeks while keeping the base food available in the same bowl. Crush or crumble a small number of insects over the base food so the smell transfers. Offer the base food first, when the hedgehog is hungriest, and add insects afterwards rather than before.

Weigh weekly throughout, and stop reducing if the weight falls.

Use insects as an earned reward for handling and for the wheel rather than as a free component of the bowl. The same number of mealworms buys far more when it is delivered one at a time.

If the hedgehog refuses the base food for more than a day, or loses weight, speak to a vet rather than pushing on.

What never to do

Do not leave a topped up bowl available permanently.

Do not feed mealworms as the main diet.

Do not feed dusted insects that have been sitting in a bowl for hours, since the powder is no longer on them.

Do not give milk, cheese or yoghurt.

Do not offer nuts, whole seeds or hard fragments.

Do not restrict food sharply to manage obesity. Weight loss in a hedgehog is planned slowly with veterinary input because of the risk of fatty liver disease.

Do not assume hind limb weakness is wobbly hedgehog syndrome without an examination.

Do not add calcium supplements to the diet on your own initiative in large amounts, because excess causes its own harm.

When to get help

Book a veterinary appointment quickly for any hind limb weakness, wobbliness, splaying or reluctance to walk, and for any hedgehog that can no longer curl into a full ball.

Contact a vet the same day for a hedgehog that has stopped eating, is losing weight, is pawing at its mouth, or has loose droppings that persist.

A hedgehog that eats its measured portion, runs on the wheel and holds a steady weight is being fed correctly.

Bring the feeding record, the exact base food including brand and the analysis panel, what insects are fed and how often, whether they are gut loaded and dusted and with what, the weekly weights, and a video of the hedgehog walking on a flat surface at home. That video is often what shows the vet the gait change most clearly.