Changes

*Formerly known as ''Bacteroides''

*Characteristics:

 

**Large Gram negative rods with terminal swellings

**Long polar fimbriae

**16 antigenic types of fimbriae - used to differentiate strains antigenically

**All strains possess same O antigen

**Colonies of virulent strains have a dark central zone, a pale granular middle zone and an irregular periphery

 

**Thermostable proteases and elastase contribute to pathogenesis

''D.nodosus'' is formerly known as ''Bacteroides''. It is a [[Pathogenic anaerobic non-spore-forming Gram-negative species - Overview|pathogenic, anaerobic, non-spore-forming Gram-negative bacteria]]. It causes foot rot in sheep, along with other bacteria.

**Keratinolytic proteases required for virulence

 

**Fimbriae required for adhesion to hoof

==Characteristics==

**Primary pathogen of epidermal tissues of hoof of ruminants, suriving briefly in the envionment

''D.nodosus'' are large rods with terminal swellings. They have long, polar fimbriae. There are 16 antigenic types of fimbriae, which can be used to differentiate strains antigenically. All of the strains possess the same O antigen.

**Passed from animal to animal

Colonies of virulent strains have a dark central zone, a pale granular middle zone and an irregular periphery.

 

Thermostable proteases and elastase contribute to the pathogenesis of ''D.nodosus''. Keratinolytic proteases are required for virulence and fimbriae are required for adhesion to hoof.

**Wet pasture and hydrated stratum corneum leads to colonisation by Gram positive cocci and [[Arcanobacter pyogenes|''Arcanobacter pyogenes'']], followed by ''F. necrophorum''; addition of ''D. nodosus'' causes footrot

 

''D.nodosus'' is a primary pathogen of epidermal tissues of the hoof of ruminants, suriving briefly in the envionment. It can be passed from animal to animal.

*Immunity:

 

**Homologous antibody to fimbrial antigen prevents adhesion and protects against footrot

==Immunity==

**Antibody must penetrate the epidermal layers and reach adequate concentration on the skin surface

A Homologous antibody to the fimbrial antigen prevents adhesion and protects against ''D.nodosus''. The antibody must penetrate the epidermal layers and reach adequate concentration on the skin surface. A vaccine is available against ''D.nodosus''. Strains can be detected by ELISA and PCR.

**Vaccine available

[[Contagious Footrot]]

[[Contagious Footrot]]

[[Category:Pathogenic_anaerobic_non-spore-forming_Gram-negative]][[Category:Sheep]]

[[Category:Pathogenic_anaerobic_non-spore-forming_Gram-negative]]

[[Category:To_Do_-_Bacteria]]

 

[[Category:To_Do_-_AimeeHicks]]