Facial Nerve Paralysis in Cows: Drooped Ear, Eyelid, and Muzzle in Cattle

Quick Answer
  • Facial nerve paralysis in cattle affects muscles of the ear, eyelid, lips, and nostril on one side of the face, so the ear may droop and the cow may not blink normally.
  • Common causes include nerve trauma, especially around the zygomatic arch or head, plus neurologic disease such as listeriosis and ear disease in calves.
  • The biggest short-term risk is eye damage because an affected cow may not blink well enough to protect and lubricate the cornea.
  • See your vet promptly if facial droop appears suddenly, if the cow is weak, circling, drooling, cannot eat normally, or has a cloudy or painful eye.
  • Many mild traumatic cases improve with time and supportive care, but recovery depends on the underlying cause and how quickly eye protection and diagnosis begin.
Estimated cost: $150–$1,800

What Is Facial Nerve Paralysis in Cows?

Facial nerve paralysis means the seventh cranial nerve is not working normally. In cattle, that nerve controls important facial movements, including blinking, ear position, lip tone, and nostril movement. When the nerve is injured or inflamed, one side of the face often looks slack or uneven.

A cow with facial nerve paralysis may have a drooped ear, a lowered eyelid, a flaccid lip, or a muzzle that pulls to the opposite side. The exact pattern depends on which branch of the nerve is affected. A more localized injury may only affect the eyelid, while a more proximal lesion can affect the ear, eyelid, lips, and nostril together.

This is a sign, not a final diagnosis. Some cases are caused by local trauma, such as pressure or injury near the cheekbone. Others are linked to deeper problems, including listeriosis, middle or inner ear disease, or other neurologic conditions. That is why a veterinary exam matters even when the facial droop looks mild.

Symptoms of Facial Nerve Paralysis in Cows

  • Drooped ear on one side
  • Inability to blink or incomplete blink
  • Lowered eyelid or widened eye opening
  • Drooped lip or muzzle asymmetry
  • Nostril asymmetry or reduced nostril movement
  • Loss of menace response with normal vision
  • Drooling or feed packing in the cheek
  • Head tilt, circling, depression, or fever

When to worry depends on what else is happening besides the facial droop. A cow with a mild isolated eyelid or ear droop after restraint trauma may still need prompt care, but a cow with facial asymmetry plus circling, salivation, trouble eating, fever, head tilt, or behavior changes needs urgent veterinary attention. Eye changes also matter. If the eye looks dry, cloudy, red, painful, or stays open, see your vet quickly because corneal injury can develop fast.

What Causes Facial Nerve Paralysis in Cows?

In cattle, facial nerve paralysis is often caused by trauma to the nerve or one of its branches. Merck notes that cattle struggling in stanchions can injure the palpebral branch where it crosses the zygomatic arch, leading to eyelid paralysis. Pressure, blunt trauma, difficult handling, or local swelling around the head can also affect the nerve.

Infectious and neurologic disease are also important causes. Listeriosis is a classic concern in cattle with one-sided facial droop, especially when it is paired with circling, depression, salivation, or other cranial nerve deficits. Merck also describes otitis media or interna in calves, including cases associated with Mycoplasma bovis, as a cause of ear droop and other facial nerve signs.

Less commonly, facial paralysis can be part of a broader brainstem or peripheral nerve disorder. Your vet may also consider toxic, inflammatory, or severe systemic neurologic disease depending on the herd history, age of the animal, feed changes, and whether other cattle are affected. Because the same outward sign can come from very different problems, the cause should not be guessed from appearance alone.

How Is Facial Nerve Paralysis in Cows Diagnosed?

Diagnosis starts with a hands-on exam and a neurologic exam. Your vet will look at ear position, eyelid closure, lip tone, nostril movement, menace response, palpebral reflex, and whether the eye retracts with third-eyelid elevation instead of blinking. They will also check for signs that the problem is limited to the facial nerve or part of a larger brainstem or ear disorder.

The history is very helpful. Your vet may ask whether the cow recently struggled in a chute or stanchion, had a head injury, developed signs after calving or transport, or has been eating silage that could raise concern for listeriosis. In calves, ear droop, fever, and vestibular signs can point toward middle or inner ear disease.

Additional testing depends on the case. This may include an eye exam with corneal stain if blinking is reduced, bloodwork, culture or other infectious disease testing, and sometimes referral-level imaging or necropsy-based confirmation in herd or severe neurologic cases. The goal is not only to confirm facial paralysis, but to identify the underlying cause so your vet can discuss realistic treatment options and prognosis.

Treatment Options for Facial Nerve Paralysis in Cows

Spectrum of Care means you have options. Here are treatment tiers at different price points.

Budget-Conscious Care

$150–$400
Best for: Stable cattle with mild, localized facial droop and no major systemic or brainstem signs
  • Farm call or clinic exam
  • Basic neurologic and eye assessment
  • Eye lubrication or protective topical support if blinking is reduced
  • Nursing care, softer feed access, and monitoring of eating and drinking
  • Observation for progression to head tilt, circling, fever, or worsening droop
Expected outcome: Fair to good in mild traumatic or pressure-related cases, especially when the eye stays healthy and signs do not progress.
Consider: Lower upfront cost, but less diagnostic detail. This approach may miss deeper causes such as listeriosis or ear disease if the case changes.
Most Common

Recommended Standard Treatment

$400–$900
Best for: Most cattle with new facial paralysis, especially when the cause is not obvious or the eye is at risk
  • Complete veterinary exam with focused neurologic localization
  • Eye protection plan and corneal stain if the eye is exposed or painful
  • Targeted treatment for the likely cause, such as therapy directed by your vet for infection, inflammation, or trauma
  • Supportive care for hydration, feed intake, and comfort
  • Short-term recheck to confirm the eye and neurologic signs are improving
Expected outcome: Variable but often reasonable when the underlying cause is identified early and the cornea is protected.
Consider: More cost and handling than conservative care, but better information and a stronger plan if the problem is infectious or progressive.

Advanced / Critical Care

$900–$1,800
Best for: Cattle with severe signs, multiple cranial nerve deficits, suspected brainstem disease, or complications such as corneal ulceration
  • Urgent or repeated veterinary visits for severe neurologic cases
  • Expanded diagnostics such as bloodwork, herd-level investigation, or referral consultation
  • Intensive treatment and nursing support for cattle with listeriosis, severe otitis, inability to eat well, or significant eye injury
  • Frequent eye monitoring and treatment if corneal ulceration develops
  • Case-by-case discussion of prognosis, welfare, and herd management implications
Expected outcome: Guarded to variable. Outcome depends heavily on the cause, severity, and how quickly treatment starts.
Consider: Highest cost range and labor needs. It can provide more answers and support, but not every cause has a favorable outcome.

Cost estimates as of 2026-03. Actual costs vary by location, clinic, and individual case.

Questions to Ask Your Vet About Facial Nerve Paralysis in Cows

Bring these questions to your vet appointment to get the most out of your visit.

  1. You can ask your vet whether this looks like an isolated facial nerve injury or part of a larger neurologic problem.
  2. You can ask your vet which signs would make listeriosis, ear disease, or head trauma more likely in this cow.
  3. You can ask your vet whether the eye is drying out or at risk for a corneal ulcer because the cow is not blinking normally.
  4. You can ask your vet what monitoring you should do at home or on the farm for eating, drinking, drooling, circling, or worsening asymmetry.
  5. You can ask your vet what conservative, standard, and advanced care options make sense for this cow’s age, use, and overall prognosis.
  6. You can ask your vet how long recovery may take if this is a traumatic nerve injury and what signs suggest permanent damage.
  7. You can ask your vet whether other cattle in the group are at risk if an infectious or feed-related cause is suspected.

How to Prevent Facial Nerve Paralysis in Cows

Not every case can be prevented, but many can be made less likely with careful handling and early attention to neurologic signs. Reduce head trauma during restraint, transport, and housing. Cattle that struggle hard in stanchions or chutes can injure the facial nerve, especially around the eyelid branch near the zygomatic arch.

Feed management also matters. Good silage practices help lower the risk of listeriosis, which is one of the more important infectious causes of one-sided facial droop in cattle. Work with your vet on herd health planning if you have recurring neurologic disease, poor-quality silage, or calves with ear infections.

Prompt treatment of ear disease and eye problems can also prevent complications. In calves, ear droop or head tilt should not be ignored. And in any cow with reduced blinking, early eye protection can prevent secondary corneal injury. Prevention is often about catching the first subtle signs before a localized problem becomes a more serious one.

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