My Dog's Back Legs Are Getting Weaker. Could It Be Neospora?

If your dog’s back legs seem weak or wobbly, and they spend time on a farm or around raw meat, neosporosis is worth mentioning to your vet. It’s caused by a microscopic parasite called Neospora caninum, and while it’s treatable when caught early, it can move fast, especially in puppies.

Here’s what you need to know.

What is neospora in dogs?

Neospora caninum is a single-celled parasite (a protozoan) that lives inside the cells of its host. Dogs are what’s called a definitive host, meaning the parasite can complete its full life cycle inside a dog’s gut, producing eggs (oocysts) that get shed in the dog’s stool. From there, those oocysts can contaminate soil, water, and food sources, continuing the cycle.

Once inside a dog, the parasite doesn’t stay in the gut. It spreads to muscle and nerve tissue, where it forms cysts and causes inflammation. In pregnant dogs, it can also cross the placenta (called transplacental or congenital infection) and infect puppies before they’re even born. Those congenitally infected puppies are often the most severely affected.

Neospora symptoms in dogs

The hallmark sign of neosporosis is progressive hind limb paralysis: weakness that starts in the back legs and gradually works its way forward. Vets call this ascending paralysis. In puppies, it can look subtle at first: a little wobbly, slow to get up, not quite keeping pace with littermates.

• Stiff or rigid hind legs: The muscles may actually feel hard to the touch. In a young puppy that seems clumsy or is falling behind the litter, this is worth a same-day call to your vet.
• Progressive weakness or difficulty standing: Weakness that gets noticeably worse over days or weeks is not something to wait out. This is one of the clearest signals to act quickly.
• Difficulty swallowing or chewing: A sign the paralysis is progressing beyond the hind limbs. If you’re seeing this alongside leg weakness, treat it as urgent.
• Muscle wasting in the hindquarters: Visible loss of muscle mass in the back legs, often from disuse as the dog compensates for weakness.
• Seizures or other neurological signs: In more severe cases. Seizures alongside any of the above symptoms are an emergency.
• Skin lesions in some dogs: Less common, but occasionally seen alongside neurological signs.

Puppies under six months are hit hardest, especially if infected in the womb. Adult dogs can get neosporosis too, but often show more generalized muscle disease rather than the classic ascending paralysis pattern.scending paralysis pattern.

Should I go to the emergency vet, or can this wait?

Call your vet and aim to be seen today if:

• Your puppy seems unusually clumsy, wobbly, or is lagging behind littermates
• Hind leg weakness has appeared in a dog with any history of raw meat consumption or farm exposure
• Muscle stiffness in the back legs is new and unexplained

Go to emergency care now if:

• Hind leg weakness is progressing rapidly over hours, not days
• Your dog can no longer stand or bear weight on their back legs
• Your dog is having seizures alongside any motor weakness
• Swallowing or chewing seems impaired alongside leg symptoms

Neosporosis moves fast, especially in puppies. Ascending paralysis that progresses unchecked can cause irreversible nerve damage. Don’t wait to see if it improves on its own.

The dog–cattle connection: why farm dogs face higher risk

Neospora caninum is one of the leading causes of cattle abortion worldwide. Cows are intermediate hosts, meaning the parasite can infect them but can’t complete its life cycle in cattle the way it can in dogs.

The cycle works like this: an infected dog sheds oocysts in its stool, which contaminate pasture or feed. Cattle eat the contaminated material and become infected. When a pregnant cow miscarries or delivers a stillborn calf, a dog might eat the placenta or fetal tissue, and that’s how the parasite gets back into the dog. Farm dogs that have access to cattle afterbirth, raw meat scraps, or infected carcasses are at significantly higher risk of picking up neospora.

If you’re on a farm or your dog roams near cattle, it’s worth talking to your vet about routine monitoring.

Diagnosis and treatment

How vets diagnose neosporosis

Diagnosing neospora in dogs usually starts with a blood test called serology, looking for antibodies your dog’s immune system has made in response to the parasite. The most common versions are ELISA (enzyme-linked immunosorbent assay) and IFA (immunofluorescent antibody test), both of which detect whether your dog has been exposed to Neospora caninum. Your vet may also recommend imaging or a spinal fluid analysis if neurological signs are present, to get a clearer picture of how much the nervous system is affected.

Is neospora in dogs curable?

Early treatment gives dogs a real chance. The standard approach is clindamycin, an antibiotic that targets the parasite and is typically given for several weeks. Some vets combine it with other medications depending on how the dog is presenting. When treatment starts before significant nerve damage sets in, many dogs respond well and can recover meaningful function.

The honest answer is: it depends on timing. Dogs with mild to moderate symptoms caught early often do well. Puppies or dogs with severe, long-standing paralysis may have lasting neurological deficits even with treatment, because nerve tissue doesn’t repair itself the way other tissue does. That’s why speed matters so much here.

How to prevent neospora in dogs

There’s no vaccine for neosporosis, so prevention comes down to managing exposure:

• Don’t feed raw meat, especially beef, venison, or other potential intermediate hosts
• Keep your dog away from cattle placentas, stillborn calves, or any animal carcasses
• Prevent access to standing water or feed that might be contaminated with cattle or dog feces
• Pick up your dog’s feces promptly, especially on farms, to break the transmission cycle
• If you have a pregnant dog with a history of exposure, talk to your vet about testing. Puppies born to infected mothers may need early monitoring.

Does pet insurance cover neosporosis treatment?

Diagnosing neosporosis isn’t cheap. Between serology panels, imaging, spinal fluid testing, and weeks of medication, costs can add up quickly, especially if your dog needs neurological specialist care.

Neosporosis is covered under a Lemonade Pet accident and illness policy, as long as it’s not pre-existing and develops after your waiting periods end. Like all pet insurance, coverage requires your dog to be enrolled before symptoms appear. Getting a policy before anything shows up is what makes coverage actually work when you need it.

Before we go

Neosporosis is the kind of condition most dog owners have never heard of – until they’re dealing with it. If you have a young puppy, a farm dog, or a dog with access to raw meat or cattle, it’s worth keeping on your radar. Hind limb weakness that progresses quickly is always a reason to call your vet, not wait and see. And if you don’t yet have a pet insurance policy, now is a good time to look into one – before symptoms ever appear.

Neospora in dogs FAQs

A few quick words, because we <3 our lawyers: This post is general in nature, and any statement in it doesn’t alter the terms, conditions, exclusions, or limitations of the policies issued, which differ according to your state of residence. You’re encouraged to discuss your specific circumstances with your own professional advisors. The purpose of this post is merely to provide you with info and insights you can use to make such discussions more productive! Naturally, all comments by, or references to, third parties represent their own views, and Lemonade assumes no responsibility for them. Coverage may not be available in all states. Please note that statements about coverages, policy management, claims processes, Giveback, and customer support apply to policies underwritten by Lemonade Insurance Company or Metromile Insurance Company, a Lemonade company, sold by Lemonade Insurance Agency, LLC.  The statements do not apply to policies underwritten by other carriers.