Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

POSTMIDTERM:LHE BACTE > Chapter 37: Pathogenic anaerobic non-spore-forming Gram-negative Bacteria > Flashcards

Chapter 37: Pathogenic anaerobic non-spore-forming Gram-negative Bacteria Flashcards

(68 cards)

Start Studying
1
Q

Often in association with

A

facultative anaerobes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Type of bacteria

A

Gram-negative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Emvironment

A

Anaerobic bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Endospores

A

Not produced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Requirement

A

Fastidious: enriched media

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Commensals in

A

Mucosal surfaces, principally in the alimentary tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Synergism with other bacteria in mixed infections

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Produces foot rot in sheep in association with other pathogens

A

Dichelobacter nodosus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

50% of this organism isolated from/ constitutes:

A

-Fusobacterium spp
-Prevotella genus
-Dichelobacter genus
-Porphyromonas genus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Usual habitat

A

-Mucous membranes of animals and humans
-Particularly in digestive and urogenital tracts
-Excreted in feces
-Survive for short periods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Differentiated based on

A

-Bacterial morphology
-Colonial appearance
-Antibiotic susceptibility testing
-Fatty acid production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Bacterial morphology:
Dichelobacter nodosus

A

-Thick, straight or slightly curved rods
-6 um long,
-bulge at one or both ends

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Bacterial morphology:
Fusobacterium necrophorum

A

-irregularly staining
-long, nom-branching filamentous forms (Fig. 37.1)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Colonies usually have

A

-Foetid or putrid ordor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Colonies have ordor due to

A

Volatile fatty acid production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Virulent strains from ovine foot rot lesions:

A

-have dark central zone
-pale granular middle zone
-spreading irregular periphery
-with a ground glass appearance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Fusobacterium necrophorum colonial appearance

A

-grey, round, shiny
-some isolates are hemolytic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Prevotella and Porphyromonas colonial appearance:

A

-Become darkly pigmented after incubation (5 days)
-May appear red under UV light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

For accurate identification of species:

A

-Antibiotic susceptibility
-Biochemical test
-Gas liquid chromatography

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Methods for detecting virulent strains of Dichelobacter nodosus:

A

-Elastin and gelatin gel test
- ELISA
-Polymerase chains reaction
-Molecular tests

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Detection of proteases activity

A

-Elastin and gelatin gel test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Using monoclonal antibodies

A

ELISA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Detection of virulence-specific genes

A

PCR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

-PCR techniques
-For grouping strains of Dichelobacter nodosus

A

Molecular tests

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Replicate only at
Low or negative reduction potentials (*Eh*)
26
Opportunistic pathogens which produces
superoxide dismutase
27
Superoxide dismutase functions
-allows them to survive in oxygenated tissues until *Eh* reaches levels favoring their growth
28
_____ and _____ followed by _____ of the bacteria can lower *Eh* levels to a range suitable for the proliferation of the bacteria
-Tissue trauma -Necrosis -multiplication of the bacteria
29
Produces heat-labile factor which stimulates *F. necrophorum* replication
*Arcanobacterium pyogenes*
30
Produces leukotoxin which correlates with the strain virulence and aids survival of *A. pyogenes*
-*F. necrophorum*
31
Is important in the pathogenesis of ruminant pedal lesions
Synergism between *F. necrophorum* and *Dichelobacter nodosus*
32
Facilitates tissue invasion by *D. nodosus* and is itself stimulated by a _____ elaborated by *D. nodosus*
-*F. necrophorum* -growth factor
33
2 or more bacteria interacting synergistically. Produce lesions which the individual organism cannot produce. Example of this type of synergism
-Production of a heat-labile factor by *Arcanobacterium pyogenes*, which stimulates *F. necrophorum* replication -In turn, *F. necrophorum* produces leukotoxin which correlates with the strain virulence and aids survival of *A. pyogenes* -Synergism between *F. necrophorum* and *Dichelobacter nodosus* is important in the pathogenesis of ruminant pedal lesions -In this instance, *F. necrophorum* facilitates tissue invasion by *D. nodosus* and is itself stimulated by a growth factor elaborated by *D. nodosus*
34
2 subsp of *F. necrophorum are recognized:
-*F. necrophorum* subsp. *necrophorum* -*F. necrophorum* subsp *funduliforme*
35
-has greater haemolytic activity -more virulent than subsp. *funduliforme*
-*F. necrophorum* subsp. *necrophorum*
36
-produces oral, -paraoral and -necrotizing pneumonic infections in horses -classified as new species
-*F. necrophorum*? -*F. equinum*?
37
*F. necrophorum* virulence factor:
-Leukotoxin -Haemagglutinins -Haemolysins -Dermotoxin -Other extracellular enzymes -Lipopolysaccharide (LPS)
38
-important virulence determinants -active against ruminant neutrophils -but may act also against macrophages and hepatocytes -moderately toxic for: equine neutrophils -little or no activity against: neutrophils of pigs and rabbits
Leukotoxin
39
-important virulence determinants -function as adhesins and promote adherence to, -and invasion of ruminal epithelial cells
-Haemagglutinins
40
-contribute to the development of ruminal lesions -important virulence determinants -endotoxin from this is important in the genesis of hepatic abscesses and induces an intense neutrophilia
Lipopolysaccharide (LPS)
41
Characteristic of *D. nodosus*
-Ability to damage tissues -production of thermostable proteases and elastase -presence of argarolytic activity on agar- based media containing powdered hoof -production of type IV fimbriae, encoded by the *fimA* gene
42
-is central to virulence -highly immunogenic structures -form basis of classification of *D. nodosus* strains into 20 serogroups
Characteristic of *D. nodosus*: -Production of type IV fimbriae, encoded by the *fimA* gene
43
Calf diphtheria
-*F. necrophorum*
44
Bovine liver abscess
-*F. necrophorum* together with *Arcanobacterium pyogenes* (feedlot animals)
45
Necrotic rhinitis of pigs (bull nose)
-*F. necrophorum*
46
Thrush of the hoof
-* F. necrophorum* -secondary to hoof damage (hind feet-frog)
47
Black spot of bovine teats
-*F. necrophorum*
48
Specific syndrome of bovine necrotic vulvovaginitis
-Association with *Porphyromonas levi* -Israeli dairy herds
49
-Straight or curved rods -characteridtic swellings at one or both ends
-*Dichelobacter nodosus*
50
-slender, non-branching filaments -stain irregularly
-*Fusobacterium necrophorum*
51
Tissue damage facilitates invasion by *D. nodosus*
*Fusobacterium necrophorum* ---> *Dichelobacter nodosus*
52
Growth factor
-*D. nodosus*----> *F. necrophorum* -*Arcanobacterium pyogenes*----> *F. necrophorum*
53
Leukotoxin facilitates survival of *A. pyogenes*
*F. necrophorum* ---> *A. pyogenes*
54
Gram-negative, non-spore-forming anaerobes which have been implicated in infections in domestic animals
14 spp. *-Bf -OBs -Bh -Dn -Fe -Fn -Fn -Fr -OFs -Pa -Pl -Ph -Pm -S*
55
(*F. necrophorum*) Predisposing factors: Rough feed producing mucosal damage -Disease condition -Species
-Calf diphtheria -Cattle
56
(*F. necrophorum*) Predisposing factors: Dystocia -Disease condition -Species
-post-partum metritis -cattle
57
(*F. necrophorum*) Predisposing factors: Sudden dietary change leading to acidosis and rumenitis -Disease condition -Species
-hepatic abscessation -cattle
58
(*F. necrophorum*) Predisposing factors: Trauma to region adjacent to teat sphincter -Disease condition -Species
-Black spot of teat -cattle
59
(*F. necrophorum*) Predisposing factors: Poor hygiene and wet housing conditions -Disease condition -Species
-thrush (hoof) -Horses
60
(*F. necrophorum*) Predisposing factors: Poor hygiene -Disease condition -Species
-Necrobacillosis of lower limbs -horses
61
(*F. necrophorum*) Predisposing factors: trauma to nasal mucosa -Disease condition -Species
-bull nose -pigs
62
(Mixed infections) Bacteria implicated: *F. necrophorum, Dichelobacter nodosus* (benign strains) -disease condition -species
-Interdigital dermatitis -sheep
63
(Mixed infections) Bacteria implicated: *Arcanobacterium pyogenes* (facultative anaerobes), *F. necrophorum* and other bacteria -disease condition -species
-heel abscess and lamellar suppuration -sheep
64
(Mixed infections) Bacteria implicated: *D. nodosus, F. necrophorum, A. pyogenes*, unidentified spirochaetes -disease condition -species
-footrot -sheep
65
(Mixed infections) Bacteria implicated: *F. necrophorum, Porphyromonas levii* -disease condition -species
-Interdigital necrobacillosis (foul-in-the-foot) -cattle
66
(Mixed infections) Bacteria implicated: *D. nodosus, F. necrophorum, Prevotella* species, spirochaetes -disease condition -species
-interdigital dermatitis -cattle
67
(Mixed infections) Bacteria implicated: *Treponema* species -disease condition -species
-Digital dermatitis -cattle
68
(Mixed infections) Bacteria implicated: Mixed anaerobes -disease condition -species
-foot abscess in young pigs and bush foot (lamellar suppuration) in older animals -pigs

POSTMIDTERM:LHE BACTE (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions