Clinical Signs / Symptoms Guide


  • Kidney/Renal disease
  • Chronic disease (e.g., lengthy course of illness, lymphoma, leukemia)

Abdomen enlarged/bloated


  • Right-sided Heart Failure
  • Disease involving the liver
  • Abdominal tumors
  • Renal disease/failure


  • Diseases of the mouth
  • Malocclusion
  • Poor diet
  • Systemic disease
  • Pain

Circling/Head Tilt

  • Otitis media/interna (ear inflammation or infection)
  • Pituitary tumor
  • Brain abscess
  • Meningitis (inflammation of the membrane that covers the brain and the spinal cord)
  • Encephalitis (inflammation of brain parenchyma)


  • Antibiotic induced
  • Environmental stress
  • Dietary issues
  • Endoparasites (e.g., helminths, protozoa)
  • Liver disease

Eye lesions / bulging

  • Cataracts
  • Keratitis due to infection (e.g., coronaviruses)
  • Corneal abrasions
  • Luxation/subluxation
  • Retrobulbar abscess

Facial Swelling

  • Salivary gland swelling – Corona virus infections (e.g., RCV/SDAV)
  • Abscessed lymph nodes
  • Dental abscess
  • Neoplasia (e.g., Zymbal’s Gland Tumor)

Hairloss (Alopecia)


Lumps, large nodules



Tail constrictions/Bumps/Necrosis

Urinary Bleeding/Discharge/Odor/Volume

  • Bacterial infection
  • Bladder stones
  • Neoplasia
  • Diabetes (increased amount of urine)
  • Renal disease (increased amount of urine)

Vaginal discharge

  • Pyometra (e.g., bacterial infection)
  • Neoplasia (e.g., uterine / ovarian tumors)
  • Dystocia (e.g., ineffective uterine contractions in birthing; a labor emergency!)
  • *Note: female rats normally experience estrus every 4-5 days (go into “heat” at fairly regular times- year round), they do not menstruate (shedding of / expelling blood).

Testicular Issues

  • Neoplasia (e.g., firm mass felt in addition to testes)
  • Cryptorchidism (e.g., one or both testes absent, or are retained permanently in the abdomen)
  1. Keeble, E. J., & Meredith, A. (2009). BSAVA manual of rodents and ferrets.(pp.342), Quedgeley: British Small Animal Veterinary Association.
  2. Keeble, E. J., & Meredith, A. (2009). BSAVA manual of rodents and ferrets.(pp.335-337), Quedgeley: British Small Animal Veterinary Association.


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