Pasteurella Infection in Rats: Respiratory Symptoms and Vet Treatment

Quick Answer
  • Pasteurella can contribute to pneumonia in rats, but many pet rats with respiratory disease also have Mycoplasma pulmonis or mixed infections.
  • Common signs include sneezing, noisy breathing, porphyrin staining around the eyes or nose, reduced appetite, lethargy, and increased effort to breathe.
  • See your vet promptly if your rat is breathing harder than normal. Open-mouth breathing, blue or gray gums, weakness, or refusal to eat are urgent signs.
  • Your vet may recommend an exam, chest imaging, and antibiotics such as doxycycline, enrofloxacin, or trimethoprim-sulfa depending on the case.
  • Typical US cost range is about $90-$220 for an exotic pet exam and basic medications, with more severe cases ranging from $300-$1,200+ if imaging, oxygen, hospitalization, or repeat visits are needed.
Estimated cost: $90–$1,200

What Is Pasteurella Infection in Rats?

Pasteurella infection in rats usually refers to respiratory disease linked to Pasteurella species, bacteria that can be involved in pneumonia and other airway infections. In pet rats, though, respiratory illness is often more complicated than one germ causing one problem. Mycoplasma pulmonis is a very common underlying cause of chronic respiratory disease, and bacteria such as Pasteurella may act as secondary or mixed infections that make signs worse.

That means a rat with sneezing or noisy breathing may not have a pure "Pasteurella infection" by itself. Instead, your vet may be treating a respiratory infection complex involving Mycoplasma, Pasteurella, other bacteria, environmental irritation, or all of these together. This is one reason rats can relapse even after they improve.

For pet parents, the most important takeaway is practical: if your rat has respiratory signs, early veterinary care matters. Rats can decline quickly, and even treatable infections may leave lasting airway damage that makes future flare-ups more likely.

Symptoms of Pasteurella Infection in Rats

  • Sneezing or frequent sniffling
  • Porphyrin staining around the eyes or nose
  • Noisy breathing, clicking, or wheezing
  • Reduced appetite or weight loss
  • Lethargy, hunching, or less grooming
  • Labored breathing, flared sides, or abdominal effort
  • Open-mouth breathing or collapse

Respiratory disease in rats can start subtly, then worsen fast. Mild sneezing may be the first clue, but noisy breathing, reduced appetite, weight loss, or visible effort to breathe are more concerning. Because rats hide illness well, a rat that looks only a little sick may already be struggling.

See your vet immediately if your rat has open-mouth breathing, blue or pale gums, marked weakness, feels cool, cannot stay upright, or stops eating. Even if signs seem mild, schedule a visit soon if they last more than a day or two, recur often, or affect more than one rat in the group.

What Causes Pasteurella Infection in Rats?

Pasteurella-related illness happens when Pasteurella bacteria colonize or overgrow in the respiratory tract, sometimes alongside other infectious agents. In rats, respiratory disease is commonly associated with Mycoplasma pulmonis, and secondary bacteria such as Pasteurella can worsen inflammation, mucus buildup, and pneumonia. Viral disease or other bacterial pathogens may also be part of the picture.

Environment matters a lot. Ammonia from dirty bedding, poor ventilation, dusty substrate, smoke, aerosols, and household fragrances can irritate the airways and make infection more likely or more severe. Stress from overcrowding, recent transport, illness, pregnancy, or introducing new rats can also lower resistance.

Spread between rats can happen through close contact, respiratory droplets, and contaminated surfaces. That is why quarantine for new rats and careful cage hygiene are so important. Your vet can help sort out whether your rat's signs fit an infectious flare, chronic respiratory disease, or both.

How Is Pasteurella Infection in Rats Diagnosed?

Diagnosis usually starts with a hands-on exotic pet exam and a careful history. Your vet will ask about sneezing, noise when breathing, appetite, bedding type, cage cleaning routine, exposure to smoke or sprays, and whether other rats are affected. In many cases, the diagnosis is based on the pattern of respiratory signs plus exam findings.

If your rat is stable enough, your vet may recommend chest X-rays to look for pneumonia, chronic lung changes, heart enlargement, or masses. In selected cases, testing may include culture, cytology, or other lab work, but these are not always practical or definitive in small patients. Because mixed infections are common, treatment is often started based on the most likely causes rather than waiting for one perfect test result.

Your vet may also assess hydration, body condition, and oxygenation, then decide whether outpatient treatment is reasonable or whether oxygen support, nebulization, injectable medications, or hospitalization are safer. Follow-up matters, because some rats improve quickly while others need longer courses or repeated care for chronic disease.

Treatment Options for Pasteurella Infection in Rats

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

Budget-Conscious Care

$90–$220
Best for: Mild to early respiratory signs in a bright, eating rat without obvious breathing distress.
  • Exotic pet exam
  • Empiric oral antibiotic plan chosen by your vet
  • Home supportive care instructions
  • Environmental cleanup and bedding review
  • Short recheck if improving as expected
Expected outcome: Often fair if treatment starts early, but relapse is possible because chronic respiratory disease is common in rats.
Consider: Lower upfront cost, but less diagnostic detail. If the rat has pneumonia, mixed infection, or chronic airway damage, symptoms may return or need escalation.
Most Common

Recommended Standard Treatment

$220–$550
Best for: Most rats with moderate respiratory signs, recurrent flare-ups, suspected lower airway disease, or incomplete response to first treatment.
  • Exotic pet exam and weight-based treatment plan
  • One or two antibiotics commonly used in rats, depending on your vet's assessment
  • Chest X-rays if breathing sounds are concerning or the rat is not improving
  • Nebulization or bronchodilator/anti-inflammatory support when appropriate
  • Recheck exam to adjust medications based on response
Expected outcome: Fair to good for many rats when treated promptly, though some will have chronic recurring signs due to Mycoplasma-associated disease or residual lung damage.
Consider: More complete evaluation and monitoring, but higher cost range and more handling, travel, and medication administration at home.

Advanced / Critical Care

$550–$1,200
Best for: Rats with open-mouth breathing, severe effort to breathe, pneumonia, dehydration, collapse, or failure of outpatient treatment.
  • Emergency or urgent exotic pet exam
  • Oxygen therapy and warming support
  • Injectable medications, fluids, and assisted feeding as needed
  • Chest imaging and additional diagnostics when the rat is stable enough
  • Hospitalization, intensive monitoring, and discharge plan for ongoing home care
Expected outcome: Guarded to fair, depending on how advanced the disease is and how well the rat responds in the first 24-72 hours.
Consider: Provides the most support for unstable rats, but cost range is higher and some critically ill rats may still have long-term respiratory problems or may not survive.

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

Questions to Ask Your Vet About Pasteurella Infection in Rats

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

  1. Do my rat's signs fit a Pasteurella infection, Mycoplasma flare, pneumonia, or a mixed respiratory problem?
  2. Is my rat stable for home treatment, or do you recommend oxygen support or hospitalization?
  3. Which antibiotic options make sense for my rat, and how long should treatment continue?
  4. Would chest X-rays change the plan today, or can we start with treatment and monitor response?
  5. Are there bedding, ventilation, or cleaning changes that could help reduce future flare-ups?
  6. Should I separate this rat from cage mates, and for how long?
  7. What signs mean the treatment is working, and what signs mean I should call right away?
  8. If this becomes a chronic issue, what conservative, standard, and advanced care options do we have over time?

How to Prevent Pasteurella Infection in Rats

Prevention focuses on lowering respiratory stress and reducing exposure to infectious organisms. Keep your rat's enclosure clean, dry, well ventilated, and low in dust. Many rats do better on paper-based bedding than on aromatic wood shavings, especially cedar or dusty substrates. Avoid cigarette smoke, vaping aerosols, candles, incense, perfume sprays, and harsh cleaners near the cage.

Quarantine new rats for at least 2 weeks before introductions, and wash your hands between groups if one rat is sick. Do not share bowls, hides, or enrichment items between a healthy group and a coughing or sneezing rat until they have been cleaned well.

Good nutrition, stable temperatures, low stress, and prompt veterinary care for early sneezing or noisy breathing can also reduce the chance of a mild flare becoming pneumonia. Some rats are prone to chronic respiratory disease despite excellent care, so prevention is about risk reduction, not perfection. If your rat has repeated flare-ups, ask your vet for a long-term management plan that fits your household and budget.

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