Curled Toe Paralysis (Riboflavin Deficiency) in Chickens
- Curled toe paralysis is a neurologic problem most often seen in growing chicks when the diet is too low in riboflavin, also called vitamin B2.
- Affected chicks may curl their toes inward, walk on their hocks, seem weak, and have trouble standing or reaching food and water.
- Early cases may improve when your vet helps correct the diet and add appropriate vitamin support, but long-standing nerve damage may not fully reverse.
- A complete age-appropriate poultry feed is the foundation of care. Scratch grains, treats, or homemade rations can dilute key vitamins if they make up too much of the diet.
- Because leg weakness can also be caused by Marek's disease, injury, toxins, or other neurologic problems, a veterinary exam is important if signs are worsening or affecting more than one bird.
What Is Curled Toe Paralysis (Riboflavin Deficiency) in Chickens?
Curled toe paralysis is a condition in young chickens linked most strongly to riboflavin deficiency, meaning the chick is not getting enough vitamin B2 in the diet. Riboflavin is important for normal nerve function and growth. When levels stay too low, the peripheral nerves can become damaged, especially the sciatic nerve, and chicks may start curling their toes inward and walking abnormally.
This problem is classically described in growing chicks, not usually in healthy adult hens on a complete ration. Birds may rest on their hocks, struggle to extend the legs normally, and become progressively weaker if the deficiency continues. In early stages, some chicks improve once the diet is corrected. If the problem has been present for too long, the nerve damage may become permanent.
For pet parents, the key point is that curled toes are a sign, not a final diagnosis. Nutritional deficiency is one important cause, but your vet may also want to rule out infectious, orthopedic, toxic, or traumatic causes of leg weakness before deciding on the best care plan.
Symptoms of Curled Toe Paralysis (Riboflavin Deficiency) in Chickens
- Toes curling inward on one or both feet
- Walking on the hocks instead of the feet
- Leg weakness or trouble standing
- Reluctance to walk, run, or keep up with flockmates
- Poor growth compared with other chicks
- Progressive inability to reach feed or water
- Recumbency or being unable to rise
Mild early signs can look subtle, especially in a busy brooder. A chick may seem clumsy, sit more often, or curl the toes only when walking. As the condition progresses, the bird may rest on the hocks and lose the ability to move normally.
See your vet promptly if your chicken cannot stand, is getting trampled, is not eating or drinking well, or if multiple birds are affected. Those patterns raise concern for a flock-level nutrition problem or another disease that can mimic riboflavin deficiency.
What Causes Curled Toe Paralysis (Riboflavin Deficiency) in Chickens?
The most common cause is a diet that does not provide enough riboflavin for growing chicks. This can happen when birds are fed an imbalanced homemade ration, too many treats or scratch grains, feed formulated for the wrong species or life stage, or old feed that has lost vitamin potency over time. Chicks have higher nutritional demands than many pet parents realize, so even well-meant feeding changes can create gaps.
Riboflavin deficiency is especially important in young birds because it affects developing nerves. Merck Veterinary Manual notes that chicks with deficiency can develop changes in the sciatic nerves, leading to the classic curled-toe paralysis pattern. Merck also notes that when the whole vitamin profile is lacking, riboflavin deficiency signs are often among the first to appear.
Not every chick with curled toes has a vitamin B2 problem. Your vet may also consider Marek's disease, avian encephalomyelitis, trauma, incubation or hatch-related deformities, slipped tendon, toxin exposure, and other vitamin or mineral imbalances. That is why a diet history and physical exam matter so much.
How Is Curled Toe Paralysis (Riboflavin Deficiency) in Chickens Diagnosed?
Your vet usually starts with a hands-on exam and a detailed feeding history. Be ready to share the exact feed name, whether it is starter, grower, or layer feed, how old the feed is, what treats are offered, and whether the bird has access to other foods. In many backyard cases, that history is one of the biggest clues.
There is not always a quick in-clinic test that confirms riboflavin deficiency in a pet chicken. Diagnosis is often based on the bird's age, the classic posture and toe curling, the diet being fed, and whether the chick improves after the ration is corrected and vitamin support is started under veterinary guidance.
Your vet may recommend additional testing if the signs are severe, one-sided, painful, or not fitting the usual pattern. Depending on the case, that can include radiographs, fecal testing, bloodwork where available, flock review, or necropsy of a deceased bird to rule out infectious or structural causes. This step is especially important if several birds are affected or if there are signs beyond the legs, such as tremors, weight loss, or sudden deaths.
Treatment Options for Curled Toe Paralysis (Riboflavin Deficiency) in Chickens
Spectrum of Care means you have options. Here are treatment tiers at different price points.
Budget-Conscious Care
- Prompt switch to a fresh, complete chick starter or grower feed appropriate for age
- Removal or major reduction of scratch grains and other low-nutrient treats
- Over-the-counter poultry vitamin support added only as directed by your vet or product label
- Supportive nursing care such as easy access to feed and water, non-slip footing, and separation from rough flockmates
Recommended Standard Treatment
- Veterinary exam with neurologic and orthopedic assessment
- Diet review and targeted plan for correcting suspected riboflavin deficiency
- Guidance on vitamin supplementation and safe supportive care
- Monitoring for hydration, body condition, and ability to compete in the flock
Advanced / Critical Care
- Everything in standard care plus imaging or additional diagnostics when indicated
- Hospital-style supportive care for birds that are weak, dehydrated, or unable to access food and water
- Flock-level investigation when multiple birds are affected
- Necropsy or referral testing if a bird dies and the diagnosis remains uncertain
Cost estimates as of 2026-03. Actual costs vary by location, clinic, and individual case.
Questions to Ask Your Vet About Curled Toe Paralysis (Riboflavin Deficiency) in Chickens
Bring these questions to your vet appointment to get the most out of your visit.
- Does this look most consistent with riboflavin deficiency, or do you think another neurologic or orthopedic problem is more likely?
- Is the feed I am using complete for this bird's age and species, or could it be contributing to the problem?
- What vitamin support do you recommend, in what form, and for how long?
- How should I set up the brooder or coop so this chick can reach food and water safely while recovering?
- What signs would mean the nerve damage may be permanent or that quality of life is declining?
- Do my other chicks need a diet review or preventive supplementation too?
- Are there signs that would make you worry about Marek's disease, avian encephalomyelitis, injury, or toxin exposure instead?
- If this bird does not improve, what would the next diagnostic step be?
How to Prevent Curled Toe Paralysis (Riboflavin Deficiency) in Chickens
Prevention starts with feeding a fresh, complete, age-appropriate poultry ration as the main diet. Chicks should be on a properly formulated starter or grower feed rather than layer feed, scratch, or a homemade mix unless that recipe has been professionally balanced. Complete feed matters because riboflavin and other vitamins are needed in small amounts but have a big effect on nerve and growth health.
Store feed in a cool, dry place and avoid using stale or poorly stored bags for young birds. If treats are offered, keep them limited so they do not crowd out balanced feed. This matters even more in small backyard flocks where a few handfuls of scratch can make up a surprisingly large share of what a chick eats in a day.
If you hatch chicks or raise mixed-age birds, review nutrition carefully with your vet. Merck notes that riboflavin deficiency can develop when feed is not formulated properly, and nutrient requirements vary by age and production stage. Early correction of diet problems protects not only one chick, but the whole flock.