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Veterinary bacteriology: information about important bacteria
Veterinary bacteriology


Species/Subspecies: Histophilus somni
Etymology: Genus name: tissue friend.
Species epithet: of sleep (refers to one of the disease conditions).
Significance:  [Important]   
Alternative Species Name(s):Haemophilus agni, Histophilus ovis, Haemophilus somnus, Haemophilus somnifer
Taxonomy:
Phylum
Proteobacteria
Class
Gammaproteobacteria
Order
Pasteurellales
Family
Pasteurellaceae 
Genus
Histophilus
Type Strain: 8025 = ATCC 43625 = CCUG 36157.
Macromorphology (smell):
 
Some strains are haemolytic. Forms small colonies (0.2-0.5 mm in diameter), which contain a yellow pigment.
Micromorphology: Small nonmotile rods
Gram +/Gram -:G-
Metabolism: Facultatively anaerobic
Catalase/Oxidase:-/+
Other Enzymes: Esculinase -, tryptophanase (+), urease -.
Fermentation of carbohydrates:
D-glucose
?
lactose
?
maltose
+
L-rhamnose
-
sucrose
-
L-arabinose
v
cellobiose
?
D-mannitol
?
salicin
?
trehalose
+
glycerol
-
inulin
-
raffinose
-
D-sorbitol
?
starch
?
Other carbohydrates: dulcitol V, D-galactose V, inositol V, melezitose -, melibiose -, xylitol ?
Spec. Char.:
Disease:
 
¨
HostsDiseaseClinical picture
Cattle (sheep, goat)Bronchopneumonia, Thrombo/TEME, with sepsisBronchopneumonia in calves the most common manifestation. Thromboembolic meningoencephalitis myocarditis, sepsis, ataxi, convulsions, blindness and sudden death.
Genome Sequence:
Acc-noStrainSize (bp)GenomeRef.
NC_008309 129PT 2 007 700 1c + 1c Nr 90

16S rRNA Seq.:
Acc-noStrainNumber of NTOperon
AF549387 (T) 1361 

Taxonomy/phylogeny:
 
Only one species have been described within genus Histophilus, which is relatively close to Nicoletella semolina, which also is a single species within its genus.
Comment:X- and V-factor are not requirements for growth in contrast to bacteria belonging to the closely related genus Haemophilus.
Reference(s): No. 63
Updated:2021-09-26

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