Changes

====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

*****Catarrhal nasal discharge (due to an acute rhinitis),  sneezing, coughing, can progress to dyspnoea and anorexia.

**Catarrhal nasal discharge (due to an acute rhinitis),  sneezing, coughing, can progress to dyspnoea and anorexia.

*****Shortening and distortion of snout, secondary to nasal turbinate bone loss (histological evidence of osteolysis)

**Shortening and distortion of snout, secondary to nasal turbinate bone loss (histological evidence of osteolysis)

*****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?

*****Colonisation of nasopharynx causing:

***Colonisation of nasopharynx causing:

*****Chronic purulent rhinitis, sinusitis, eustachitis

***Chronic purulent rhinitis, sinusitis, eustachitis

*****Can progress to development of nodular masses in the guttural pouch consisting of inspissated pus and viable bacteria (guttural pouch empyema) - 'carrier' state

***Can progress to development of nodular masses in the guttural pouch consisting of inspissated pus and viable bacteria (guttural pouch empyema) - 'carrier' state

*****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

*****Aspergillus fumigatus

*****Aspergillus fumigatus