Lapis ISSN 2398-2969


Contributor(s): Narelle Walter, Susan Brown, Stephen Hernandez-Divers, Maud Lafortune, Vetstream Ltd


  • Pneumonia is inflammation of the lung parenchyma.
  • Respiratory disease is a major cause of both morbidity and mortality in pet rabbits. It is often presented in advance stages of respiratory compromise.
  • Pasteurellosis   Pasteurellosis   historically quoted as the primary respiratory disease of rabbits.
  • As more pet rabbits make the transition from the garden hutch to the heated home so changes in temperature, ventilation, humidity and environmental pollutants may alter the epidemiology of respiratory diseases.
  • Infectious bronchitis and pneumonia has been well documented since the 1920s.
  • May be a secondary or concurrent condition, with underlying disease or immunodeficiency predisposing animals to pneumonia.
  • Several bacterial and viral pathogens can cause pneumonia.
  • Non-infectious bronchitis and pneumonia may become more important in the home environment and may be caused by:
    • Allergies.
    • Respiratory insults (smoke, aerosols).
  • Signs: lethargy and malaise, fever, anorexia and weight loss, dyspnea and tachypnea, oculonasal discharge, pale to congested mucous membranes, sneezing and coughing.
  • Treatment: correction of underlying factors including poor nutrition and poor environment, antimicrobials and surgical resection if indicated.
  • Diagnosis: based upon history, clinical signs, hematology, radiography, endoscopy, ultrasonography, and lung wash or lung biopsy.
  • Prognosis: depends on disease and severity but often guarded given the advanced presentation of most cases.

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  • Presentation depends upon:
    • Nature of the pneumonia, infectious or non-infectious.
    • Virulence of organism.
    • Age and immunocompetence of the rabbit.
  • In most cases rabbits present with one or more of the following:
    • Lethargy, malaise and/or unkempt appearance.
    • Fever.
    • Anorexia and weight loss.
    • Dyspnea and tachypnea.
    • Oculonasal discharge.
    • Pale to congested mucous membranes or cyanosis.
    • Sneezing and coughing.
  • It is important to realize that many rabbits will mask obvious symptoms of pneumonia until the disease is very advanced.
  • Any rabbit showing even mild lower respiratory tract signs should be considered seriously ill until proven otherwise.
  • Pasteurellosis may cause a myriad of presentations of which respiratory signs may be only one manifestation.


  • Rabbits with acute or peracute pneumonia may simply present as sudden deaths.
  • Signs, if noticed, may include:
    • Severe dyspnea   Dyspnea  with increased respiratory noise.
    • Lateral or ventral recumbency.
    • Open mouth breathing with extended neck.
    • Cyanotic mucous membranes.
    • Hemoptesis (coughing blood).
    • Anorexia   Anorexia  .
    • Fever or shock hypothermia   Hypothermia  .


  • The authors are unaware of any studies that have determined the incidence of respiratory disease in pet rabbits.
  • Incidence of pneumonia increases with the following:
    • Age.
    • Underlying concurrent disease.
    • Stress.
    • Overcrowding.
    • Poor husbandry.
    • Immunodeficient animals. 


  • The incidence and prevalence of disease is increased where temperature fluctuations occur as is more likely in temperate regions. Rabbits exposed to excessively high temperatures in tropical environments may also suffer respiratory embarrassment.
  • Temperature variation will be more significant for hutch-housed rabbits than house rabbits. However, house rabbits may be kept too warm in centrally heated homes.
  • Distribution of pathogens:
    • Most bacterial pathogens appear to have a worldwide distribution.
    • Herpesvirus has been reported in Europe and Canada.
    • Coronavirus (pleural effusion disease): worldwide distribution unknown, incidence low, first reported in Scandinavia, appears restricted to labs.
    •  Chlamydia: appears to be an experimentally induced infection (human model for Chlamydial pneumonia) but natural infection appears rare.
  • Housing and environment may affect disease:
    • Outside hutch and run provide better ventilation but greater temperature fluctuations.
    • House rabbits have a more stable environment but it may be too warm and too dry.


  • Incidence of infection varies:
    • With breed, greater in Flemish Giant   Flemish Giant  than in New Zealand White   New Zealand White  .
    • With season, greater in spring and autumn.
    • With temperature, greater with temperature fluctuations and excessively high temperatures.
  •  Bordetella bronchiseptica  Bordetella bronchiseptica  may be co-pathogen or predisposing factor to Pasteurellaspp   Pasteurella multocida  .
  •  Bordetellaspp appears to be more common in neonatal/juvenile rabbits while Pasteurellaspp is more common in adults.
  • Up to 60% of rabbits may carry subclinical Pasteurellaspp and of that infected population:
    • 40% may develop clinical signs of respiratory disease.
    • 10% may spontaneously recover.
    • 5% may develop pneumonia.
    • 5% may develop bacteremia.
  •  Pasteurella-free status is possible only in SPE laboratory populations.
  • The numbers of rabbits experiencing clinical pneumonia is quite low but subclinical disease, often as an extension of upper respiratory disease, is very common.



  • Costs will depend on the level of investigation and the duration of therapy.
  • Standard investigation, ie consultation, hematology, anesthesia, radiographs, endoscopy, lung wash cytology or lung biopsy for histopathology and microbiology, prolonged antibiotic therapy.
  • Thoracotomy and abscess removal will necessitate extensive surgery and critical care nursing.

Special risks

  • Blood can be collected from the conscious animal, but radiographs, lung wash or biopsy require sedation   Sedation  or general anesthesia   Anesthesia: overview  .
  • Respiratory disease does add a significant risk to anesthesia, which must be weighed against the benefits of making a diagnosis. However, short anesthetic restraint greatly facilitates the collection of diagnostic samples and reduces stress of sample collection, thereby ultimately providing a definitive diagnosis and prognosis.


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Further Reading


Refereed papers
  • Recent references fromPubMed.
  • Roels S, Wattiau P, Fretin D, Butaye P & Vanopdenbosch E (2007)Isolation of Morganella morganii from a domestic rabbit with bronchopneumonia. Vet Rec161(15), 530-531 PubMed.
  • Deeb B J & DiGiacomo R F (2000)Respiratory diseases of rabbits. Vet Clin North Am Exot Anim Pract3(2), 465-480PubMed.
  • Langan G P, Lohmiller J J, Swing S P & Wardrip C L (2000)diseases of rodents and rabbits. Vet Clin North Am Small Anim Pract30(6), 1309-1335.
  • Hyde D M, Downey G P, Tablin F, Rosengren S, Giclas P C, Henson P M & Worthen G S (1997)Age-dependent neutrophil and blood flow responsiveness in acute pulmonary inflammation in rabbits. Am J Physiol272(3), 471-478PubMed.
  • Mazars E, Guyot K, Durand I, Dei-Cas E, Boucher S, Abderrazak S B, Banuls A L, Tibayrenc M & Camus D (1997)Isoenzyme diversity in Pneumocystis carinii from rats, mice and rabbits. J Infect Dis175(3), 655-660PubMed.
  • Ramirez-Romero R, Brogden K A & Cutlip R C (1997)Influence of immunization on the pulmonary inflammatory response of rabbits induced by Pasteurella haemolytica A1 lipopolysaccharide. J Comp Pathol117(2), 137-145PubMed.
  • Richardson M, Fletch A, Delaney K, DeReske M, Wilcox L H & Kinlough-Rathbone R L (1997)Increased expression of vascular cell adhesion molecule-1 by aortic endothelium of rabbits with Pasteurella multocida pneumonia. Lab Anim Sci47(1), 27-35.
  • Moazed T C, Kuo C, Patton D L, Grayston J T & Campbell L A (1996)Experimental rabbit models of Chlamydia pneumoniae infection. Am J Physiol48(2), 667-676.
  • Vemau K M, Grahn B H, Clarke-Scott H A & Sullivan N (1995)Thymoma in a geriatric rabbit with hypercalcaemia and periodic exophthalmos. JAVMA206, 820-822.
  • DiGiacomo R F, Deeb B J, Brodie S J et al(1993)Toxin production by Pasteurella multocida isolated from rabbits with atrophic rhinitis. Am J Vet Res54, 1280-1286.
  • DeLong D, Manning P J, Gunther R et al(1992)Colonization of rabbits by Pasteurella multocida - serum IgG responses following intranasal challenge with serologically distinct isolates. Lab Anim Sci42, 13-19.
  • Dugal F, Bdlanger M & Jacques M (1992)Enhanced adherence of Pasteurella multocida to porcine tracheal rings preinfected with Bordetella bronchiseptica. Can J Vet Res56, 260-264.
  • Onderka D K, Papp-Vid G & Perry A W (1992)Fatal herpesvirus infection in commercial rabbits. Can Vet J33(8), 539-543.
  • Zimmerman T E, Deeb B J & DiGiacomo R F (1992)Polypeptides associated with Pasteurella multocida infection in rabbits. Am J Vet Res53, 1108-1112.
  • Broome R L & Brooks D L (1991)Efficacy of enrofloxacin in the treatment of respiratory pasteurellosis in rabbits. Lab Anim Sci41, 572-576.
  • Chdsp C E & Foged N T (1991)Induction of pneumonia in rabbits by use of a purified protein toxin from Pasteurella multocida. Am J Vet Res52, 56-61.
  • Choi-Kim K, Meheswaran S K, Felice U et al(1991)Relationship between the iron regulated outer membrane proteins and the outer membrane proteins of in vivo grown Pasteurella multocida. Vet Microbiol28, 75-92.
  • Gunther R, Manning P I, Bouma J E et al(1991)Partial characterization of plasmids from rabbit isolates of Pasteurella multocida. Lab Anim Sci41, 423-426.
  • Lu Y S, Lai W C, Pakes S P et al(1991)A monoclonal antibody against a Pasteurella multocida outer membrane protein protects rabbits and mice against pasteurellosis. Infect Immunol59, 172-180.
  • Zaoutis T E, Reinhard G R, Cioffe C J et al(1991)Screening rabbit colonies for antibodies to Pasteurella multocida by an ELISA. Lab Anim Sci41, 419-422.
  • Deeb B J, DiGiacomo R F, Bernard B L et al(1990)Pasteurella multocida and Bordetella bronchiseptica infections in rabbits. J Clin Microbiol28, 70-75.
  • DiGiacomo R F, Taylor F G R, Allen V et al(1990)Naturally acquired Pasteurella multocida infection in rabbits - immunologic aspects. Lab Anim Sci40, 289-292.
  • Glavits R & Magyar T (1990)The pathology of experimental respiratory infection with Pasteurella multocida and Bordetella bronchiseptica in rabbits. Acta Vet Hung38, 211-215.
  • Kurisu K, Kyo S, Shiomoto Y et al(1990)Cilia-associated respiratory bacillus infection in rabbits. Lab Anim Sci40, 413-415.
  • Okerman L, DeVriese L A, Maerten L et al(1990)In vivo activity of orally administered antibiotics and chemotherapeutics against acute septicaemic pasteurellosis in rabbits. Lab Anim24, 341-344.
  • DiGiacomo R F, Deeb B J, Giddens W E et al(1989)Atrophic rhinitis in New Zealand White rabbits infected with Pasteurella multocida. Am J Vet Res50, 1460-1465.
  • Foged N T, Nielsen J P & Jorsal S E (1989)Protection against progressive atrophic rhinitis by vaccination with Pasteurella toxin purified by monoclonal antibodies. Vet Rec125, 7-11.
  • Shell L G & Saunders G (1989)Arteriosclerosis in a rabbit. JAVMA194, 679-680.
  • Spreadbury C L, Krausz T, Pervez S & Cohen J (1989)Invasive aspergillosis: clinical and pathological features of a new animal model. J Med Vet Mycol27(1), 5-15.
  • Ikeda J S & Hirsh D C (1988)Antigenically related iron-regulated outer membrane proteins produced by different somatic serotypes of Pasteurella multocida. Am J Vet Res56, 2499-2502.
  • Al-Lebban Z S et al(1988)Rabbit pasteurellosis - induced disease and vaccination. Am J Vet Res49(3), 312-320.
  • Duclos P, Caillet J & Javelot P (1986)Flore bacterienne aerobie des cavites nasales du lapin d'elevage. Ann Rech Vet17, 185-190.
  • Nakagawa M, Nakayama K, Saito M et al(1986)Bacteriological and serological studies on Pasteurella multocida infection in rabbits. Jikken Dobutsu35, 463-469.
  • Zeligs B J, Zeligs J D & Bellanti J A (1986)Functional and ultrastructural changes in alveolar macrophages from rabbits colonized with Bordetella bronchiseptica. Infect Immunol53, 702-706.
  • Anderson L C, Rush H G & Glorioso J C (1984)Strain differences in the susceptibility and resistance of Pasteurella multocida to phagocytosis and killing by rabbit polymorphonuclear neutrophils. Am J Vet Res45, 1193-1198.
  • Percy D H, Prescott J F & Bhasin J L (1984)Characterization of Pasteurella multocida isolated from rabbits in Canada. Can J Comp Med48, 162-165.
  • Corbeil L B, Strayer D S, Skaletsky E et al(1983)Immunity to pasteurellosis in compromised rabbits. Am J Vet Res44, 845-85.
  • DiGiacomo R F, Garlinghouse L E & Van Hoosier G L (1983)Natural history of infection with Pasteurella multocida in rabbits. JAVMA183, 1172-1175.
  • Glorioso J C, Jones G W, Rush H G et al(1982)Adhesion of type A Pasteurella multocida to rabbit pharyngeal cells and its possible role in rabbit respiratory tract infections. Infect Immunol35, 1103-1109.
  • Lu Y S, Pakes S P, Rehg J E et al(1982)Pathogenicity of serotype 12 - A Pasteurella multocida in hydrocortisone treated and non-treated rabbits. Lab Anim Sci32, 258-262.
  • Mushin R & Schoenbaum M (1980)A strain of Pasteurella multocida associated with infections in rabbit colonies. Lab Animal14353-356.
  • Patton N M, Holmes H T, Caveny D D et al(1980)Experimental inducement of snuffles in rabbits. J Appl Rabbit Res3, 8-12.
  • Okerman L, Spanoghe L & DeBruycker R M (1979)Experimental infections of mice with Pasteurella multocida strains isolated from rabbits. J Comp Pathol89, 51-55.
  • Lu Y S, Ringler D H & Park J S (1978)Characterization of Pasteurella multocida isolates from the nares of healthy rabbits and rabbits with pneumonia. Lab Anim Sci28, 691-697.
  • Stephen G W & Cooper L V (1977)The role of analgesics in respiratory depression: a rabbit model. Anaesthesia32(4), 324-327.
  • Watson W T, Goldsboro J A, Williams F P et al(1975)Experimental respiratory infection with Pasteurella multocida and Bordetella bronchiseptica in rabbits. Lab Anim Sci25, 459-464.
  • Deeb B J and Kenny G E (1967)Characterization of Mycoplasma pulmonis variants isolated from rabbits - 1. identification and properties of isolates. J Bacteriol93, 1416-1424.
  • Hagen K W (1958)Enzootic pasteurellosis in domestic rabbits - 1. pathology and bacteriology. JAVMA133, 77-80.

Other sources of information

  • Johnson D (2011)Pneumonia in Small Mammals.In: Proc Association of Avian Veterinarians Conference.
  • Kelleher S (2008)Rabbit Respiratory Disease.In: Proc Western Veterinary Conference.
  • Murray M J (2006)Rabbits it's not always Pasteurella.In: Proc North American Veterinary Conference.
  • Hoefer H (2001)Rabbit Respiratory Disease.In: Proc Atlantic Coast Veterinary Converence.
  • DiGiacomo R F & Mare C J (1994)Viral diseases.In: Biology of the Laboratory Rabbit.Eds: P Manning, D H Ringler & C E Newcomer. Academic Press, Orlando, Florida. pp 171-204.
  • Cohen J O (1991)Staphylococcus.In: Medical Microbiology.Ed: S Baron. Churchill Livingstone, New York. pp 203-214.
  • Manning P J, DiGiacomo R F & DeLong D (1989)Pasteurellosis in laboratory animals.In: Pasteurella and Pasteurellosis.Ed: C Adlam & J M Rutter. Academic Press, London. pp 263-302.
  • Rimler R B & Rhoades K R (1989)Pasteurella multocida.In: Pasteurella and Pasteurellosis.Eds: C Adlam & J M Rutter. Academic, London. pp 37-73.
  • Flatt R E (1974)Bacterial diseases.In: Biology of the Laboratory Rabbit.Eds: S H Weisbroth, R E Flatt & A K Kraus. Academic Press, New York. pp 193-236.