Hedgehog food safety: wild insects, raw meat, lungworm, and what a faecal test actually finds

Quick answer

Commercially raised feeder insects on a base diet. Where the insects came from matters more to a hedgehog's health than which insects they are.

The raw feeding debate was written for dogs and cats and does not transfer to an insectivore. A hedgehog already eats whole raw prey when it eats insects, so the question is not raw versus cooked. It is what the food carries into the animal.

Two things carry risk. Anything caught outdoors can carry parasites, and slugs, snails and earthworms in particular are the intermediate hosts for lungworm. Anything raw from the kitchen can carry Salmonella, which hedgehogs shed to people as well as to each other.

• Feed captive-bred feeder insects from a supplier who breeds them. Do not collect insects, slugs, snails or worms from a garden.
• Slugs, snails and earthworms are the single highest-risk food item you can offer a hedgehog.
• Raw meat and raw egg carry Salmonella, and hedgehogs are recognised carriers that can shed it while looking perfectly well.
• A routine faecal flotation does not detect lungworm larvae. Ask specifically for the test that does.
• Blind worming is not a substitute for a diagnosis. Different parasites need different drugs, and some need none.

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Never feed a hedgehog wild-caught slugs, snails or earthworms.

They are the intermediate hosts for lungworm. The larvae migrate from the gut to the lungs, and the disease that follows presents as coughing, laboured breathing and weight loss. In wild hedgehog populations it is one of the commonest causes of death.

There is a second hazard in the same handful. Slugs and snails from any garden may have taken up molluscicide bait, and a hedgehog that eats a poisoned slug takes the poison with it.
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Decide in 60 seconds

Why the dog raw-feeding argument does not apply

A hedgehog is an insectivore. Its natural diet is whole invertebrates: beetles, caterpillars, worms and other small prey, eaten alive and entire.

Its gut reflects that. The tract is short and simple, there is no caecum for fermentation, and food passes through quickly. That is efficient for a diet of soft-bodied prey and unforgiving of anything that irritates the bowel.

So the question raw feeders ask about dogs, whether raw is better than cooked, is already answered for a hedgehog. It eats raw prey by default.

The useful questions are different ones. Where did the food come from. What is living in it. What is the ratio of calcium to phosphorus in the whole animal being eaten. Is the exoskeleton digestible at the size being offered.

A great deal of harm gets done by importing a framework built for a carnivore. Owners construct minced raw meat diets for an animal that in the wild would rarely eat vertebrate flesh, and in doing so they add a pathogen risk and remove the whole-prey calcium that insects provide.

What comes in with the food

Lungworm.

Acquired by eating slugs, snails and earthworms carrying the larvae. The larvae leave the gut, reach the lungs, and mature there. The result is coughing, increased breathing effort, nasal discharge, weight loss and, in heavy infections, death. This is the reason the wild-food rule is absolute rather than cautious.

Much of the published work is on wild European hedgehogs rather than the African pygmy hedgehog kept as a pet, because that is the population that gets examined. The route of infection is the same for any hedgehog that eats the same intermediate hosts.

Intestinal worms.

Capillaria and other nematodes produce weight loss, poor coat and diarrhoea. Some are acquired directly from a contaminated environment rather than from food, which is why a filthy enclosure sustains an infection that treatment keeps failing to clear.

Coccidia.

Single-celled parasites spread faecal to oral rather than through food. They cause diarrhoea and are hardest on young, newly moved or otherwise stressed animals. Wormers do nothing to them: they need a specific anticoccidial drug.

Cryptosporidium.

Another single-celled parasite, difficult to treat and transmissible to people. It matters particularly in households with a young child, an elderly person or anyone immunosuppressed.

Salmonella.

Carried in raw meat, raw egg, and by hedgehogs themselves. Infected hedgehogs frequently show nothing at all while shedding the organism in their droppings. Human infections traced to contact with pet hedgehogs are documented, which is why hand washing after handling is not a formality.

Toxoplasma and other meat-borne organisms.

Raw meat, particularly raw pork and raw offal, carries risks that cooking removes. If meat is fed at all, cooked plain meat carries a fraction of the risk of raw.

Chemical contamination.

Insects from a treated garden carry insecticide. Slugs from anywhere near bait carry molluscicide. Neither is visible.

What a faecal test actually finds, and what it misses

Weighing the food and weighing the animal are both part of this. Accurate weight is what a correct parasite dose is calculated from, and weight loss is usually the first measurable sign of a parasite burden.

There is no single "worm test". The laboratory chooses a technique, and the technique determines what can be found.

Flotation suspends the sample in a dense solution so that worm eggs and coccidial oocysts rise and can be collected. It is the routine test and it finds most intestinal parasites.

Direct smear looks at a small amount of fresh material under the microscope. It finds motile organisms that flotation would kill or distort.

Sedimentation catches heavier eggs that will not float.

Larval recovery, usually a Baermann technique, is what finds lungworm. It works by letting larvae migrate out of the sample into water over several hours. A standard flotation will not reliably show them.

That last point is the one to take to the appointment. If your hedgehog is coughing and the practice runs a routine flotation that comes back clear, lungworm has not been excluded.

Two practical details change the result more than most owners expect. The sample must be fresh, and refrigerated rather than frozen, because freezing destroys some structures. And shedding is intermittent, so a pooled sample collected across three consecutive days is far more sensitive than one dropping.

Why blind worming fails

A wormer is not a general-purpose cleaner. Each drug covers a specific range of organisms.

A product effective against intestinal nematodes does nothing to coccidia. A treatment for coccidia does nothing to lungworm. A treatment for lungworm may need a different drug and a different route from the one in the cupboard.

Dosing is the second problem. Almost all parasite treatment in hedgehogs is off-label, extrapolated by a vet from other species, and calculated on body weight. A hedgehog is small enough that a rough estimate of weight produces a meaningfully wrong dose. Accurate kitchen scales are part of the treatment.

The third problem is the one that costs animals their lives. Weight loss and poor coat have several causes, and parasites are only one. Dental disease, a tumour, kidney disease and heart disease all produce the same picture. Reaching for a wormer and waiting to see whether it works spends the weeks that a treatable diagnosis needed.

Repeated blind treatment also selects for resistance, which matters in a household with several animals.

Sourcing food so nothing comes in with it

A food bowl standing on loose bedding collects droppings and substrate between meals. Feeding on a wipeable surface or a tile makes contamination visible and the bowl easy to clean properly.

Buy live insects from a supplier that breeds them rather than collects them. Captive colonies are raised on known feed, in a controlled environment, without exposure to garden chemicals or wild intermediate hosts.

Gut load them before feeding. Insects transfer what is in their own gut, so a well fed insect is a better meal and a starved one is close to an empty shell.

Never collect insects, slugs, snails or earthworms from outdoors, and never let a pet hedgehog forage in a garden where it can find them itself. That is the same rule stated two ways.

Avoid wild-caught beetles in particular. Several beetle families carry defensive chemicals, and fireflies are known to be lethal to insectivorous reptiles, so there is no case for experimenting.

Treat freeze-dried and canned insects as the low-risk option. Heat and drying remove living pathogens. They are not nutritionally identical to live insects, and a diet built mainly on dried mealworms creates a separate calcium problem, so use them as part of a mixed diet rather than as the whole of it.

Store insect and dry food where it stays cool and dry. Fat goes rancid, storage mites colonise opened bags, and mould in damp food produces toxins that no amount of sorting removes.

If you feed any fresh food, treat the kitchen as you would for yourself. A separate board, hands washed immediately, and no rinsing of bowls in a sink where food is prepared.

Feeding hygiene at night

Hedgehogs eat after dark, so food goes into the bowl in the evening and sits there for hours in a heated enclosure. That is a bacterial incubator.

Wet food, raw food and fresh food should be removed within a couple of hours rather than left until morning. Dry food can stay down.

Wash bowls daily with hot soapy water. A film in the bottom of a bowl is biofilm, and rinsing does not remove it.

Keep the food bowl off loose bedding, ideally on a tile or a wipeable mat, so that droppings and substrate do not end up in it and so you can see when it needs cleaning.

Do not let a hedgehog eat in its litter area, and clean the wheel daily, since most hedgehogs defecate while running and then walk through it.

Changes that mean act today

Any cough, wheeze, click or visible breathing effort.

Respiratory signs in a hedgehog are never minor, and lungworm sits alongside pneumonia and heart disease on the list of causes. Same-day appointment.

Diarrhoea lasting more than a day, or any blood.

A short episode after a food change can be benign. A persistent one dehydrates an animal this size quickly.

Weight loss on the weekly record, even with normal appetite.

Parasites, dental disease and tumours all look like this. The scales notice before you do.

Green droppings that persist.

Green stool often means food is passing too fast, which happens in gut infections and when a hedgehog has stopped eating properly.

Anyone in the household with unexplained gastrointestinal illness.

Mention the hedgehog to your doctor. Salmonella and Cryptosporidium both travel from the animal to people, and that connection is easily missed if nobody raises it.

The routine that keeps this under control

What never to do

Never feed slugs, snails or earthworms from a garden, however organic that garden is.

Never let a hedgehog roam unsupervised outdoors where it can hunt its own invertebrates.

Never feed raw egg. Beyond the Salmonella risk, raw egg white contains avidin, which binds biotin and interferes with its absorption. Cooked egg does not have this problem.

Never worm on a schedule as a substitute for testing. Routine calendar worming is a livestock model and it does not fit a single indoor animal.

Never assume a healthy-looking hedgehog is not carrying Salmonella. Carriage without illness is the normal pattern.

Never feed cow's milk. Adult hedgehogs digest lactose poorly and it produces diarrhoea in an animal that has very little tolerance for fluid loss.

Never treat both parasites and a diet change at the same time when investigating diarrhoea. If it resolves, you will not know which one worked, and that matters when it comes back.

When to get help

Water is the only liquid a hedgehog needs. Milk is not a treat for a hedgehog: adults digest lactose poorly, and diarrhoea in an animal this small becomes a dehydration problem quickly.

Go the same day for coughing, laboured or noisy breathing, blood in the droppings, diarrhoea with lethargy, a hedgehog that has stopped eating, or a hedgehog that feels cold and will not uncurl.

Book promptly, rather than same day, for persistent green or loose stool in an otherwise bright animal, a weight trend heading downward, or a recent history of eating something wild.

The vet will want the exposure history: what the hedgehog eats, where the insects come from, whether it has outdoor access, whether it has ever eaten a slug or snail, what else lives in the house, and whether anyone at home has been unwell.

They will want the weight record, and they will want a fresh pooled stool sample rather than one dropping.

Expect a faecal examination, and ask directly for a larval technique if there are any respiratory signs. Expect that a first negative result may need repeating, because shedding is intermittent and a single clear sample proves less than it appears to.

If treatment is prescribed, the dose depends on an accurate weight, so weigh the animal on the day rather than quoting a figure from last month.