Changes

*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. [[Pasteurella species and Mannheimia haemolytica|''P.multocida'']] adheres poorly to mucous membranes, and therefore requires a predisposing nasal insult to assist colonisation eg: co-infection with [[Bordetella bronchiseptica and Bordetella avium|''B.bronchoseptica'']] or [[Cytomegalovirus|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. [[Pasteurella species and Mannheimia haemolytica|''P.multocida'']] adheres poorly to mucous membranes, and therefore requires a predisposing nasal insult to assist colonisation eg: co-infection with [[Bordetella bronchiseptica and Bordetella avium|''B.bronchiseptica'']] or [[Cytomegalovirus|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 [[Bordetella bronchiseptica and Bordetella avium|''B.bronchoseptica'']] strains alone, that carry a gene that encodes for a dermonecrotic toxin.

***Due to infection of the nasal turbinates by [[Bordetella bronchiseptica and Bordetella avium|''B.bronchiseptica'']] 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===

===Snuffles===

*Caused by [[Pasteurella species and Mannheimia haemolytica|''Pasteurella multocida'']], less commonly and/or [[Bordetella bronchiseptica and Bordetella avium|''B.bronchoseptica'']]

*Caused by [[Pasteurella species and Mannheimia haemolytica|''Pasteurella multocida'']], less commonly and/or [[Bordetella bronchiseptica and Bordetella avium|''B.bronchiseptica'']]

*Clinical signs (nasal discharge, sneezing) result from an acute to chronic [[Nasal Cavity Inflammatory - Pathology|rhinitis]]

*Clinical signs (nasal discharge, sneezing) result from an acute to chronic [[Nasal Cavity Inflammatory - Pathology|rhinitis]]