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Diseases of the nasal cavity and sinuses (view source)
Revision as of 10:02, 1 February 2007
, 10:02, 1 February 2007→Bacterial infections
====Bacterial infections====
====Bacterial infections====
*Pasturella multocida
*''Pasturella multocida''
**Atrophic rhinitis in pigs
**Atrophic rhinitis in pigs
**Pigs aged 4-12 weeks old show clinical signs
**Pigs aged 4-12 weeks old show clinical signs
**2 forms of the disease
**2 forms of the disease
***'Progressive' atrophic rhinitis
***'Progressive' atrophic rhinitis
****Due to infection of the nasal turbinates by P.multocida strains carrying the toxA gene that encodes for an osteolytic toxin. P.multocida adheres poorly to mucous membranes, and therefore requires a predisposing nasal insult to assist colonisation eg: co-infection with B.bronchoseptica; or Porcine cytomegalovirus (inclusion body rhinitis)
****Due to infection of the nasal turbinates by P.multocida strains carrying the toxA gene that encodes for an osteolytic toxin. ''P.multocida'' adheres poorly to mucous membranes, and therefore requires a predisposing nasal insult to assist colonisation eg: co-infection with ''B.bronchoseptica''; or Porcine cytomegalovirus (inclusion body rhinitis)
****Turbinate bone atrophy is permanent and progressive
****Turbinate bone atrophy is permanent and progressive
***'Non-progressive' atrophic rhinitis
***'Non-progressive' atrophic rhinitis
****Due to infection of the nasal turbinates by Bordatella bronchoseptica strains alone, that carry a gene that encodes for a dermonecrotic toxin.
****Due to infection of the nasal turbinates by ''Bordatella bronchoseptica'' strains alone, that carry a gene that encodes for a dermonecrotic toxin.
****Turbinate bone can regenerate by the time of slaughter
****Turbinate bone can regenerate by the time of slaughter
**'Snuffles' in rabbits
**'Snuffles' in rabbits
****Most often P.multocida and/or B.bronchoseptica infection of the nasal mucosa
****Most often ''P.multocida'' and/or ''B.bronchoseptica'' infection of the nasal mucosa
****Clinical signs (nasal discharge, sneezing) result from an acute to chronic rhinitis.
****Clinical signs (nasal discharge, sneezing) result from an acute to chronic rhinitis.
*Streptococcus equi
*''Streptococcus equi''
**Streptococcus equi subsp. equi
**''Streptococcus equi subsp. equi''
***Cause of 'Strangles' in horses
***Cause of 'Strangles' in horses
***Infection with Streptococcus equi occurs after contact with contaminated feed, water bowls or an infected carrier horse
***Infection with ''Streptococcus equi'' occurs after contact with contaminated feed, water bowls or an infected carrier horse
***Organism remains viable in environment for months
***Organism remains viable in environment for months
***Possibility of other sources of infection - in pharynx of in-contact dogs?
***Possibility of other sources of infection - in pharynx of in-contact dogs?
***Regional suppurative lymphadenitis - can rupture onto skin of neck
***Regional suppurative lymphadenitis - can rupture onto skin of neck
***Bacteraemia with abscess formation in other organs (eg: liver, kidneys) - Bastard Strangles!
***Bacteraemia with abscess formation in other organs (eg: liver, kidneys) - Bastard Strangles!
**Streptococcus equi subsp. zooepidemicus
**''Streptococcus equi subsp. zooepidemicus''
***Can infect the respiratory tract (nasal cavity, paranasal sinuses, trachea and bronchi/bronchioles)
***Can infect the respiratory tract (nasal cavity, paranasal sinuses, trachea and bronchi/bronchioles)
***URT infection can be indistinguishable clinically from Strangles, but does not cause suppurative lymphadenitis (cf: S.equi subsp. equi)
***URT infection can be indistinguishable clinically from Strangles, but does not cause suppurative lymphadenitis (cf: ''S.equi subsp. equi'')
====Fungal infections====
====Fungal infections====
*Filamentous fungal organisms
*Filamentous fungal organisms