Bacteria

Question 1

Anthrax

Pathogen + susceptibility

Answer 1

Bacillus anthracis
All warm-blooded mammals & birds

Notifiable
Zoonotic

Question 2

Malignant oedema

Pathogen + susceptibility

Answer 2

- Clostridium septicum
(a, b, d, g)
- C. novyi
(toxins + lipase, lecitinase)
- C. histolyticum
(toxins + proteases)
- C. sordelli
(toxins)

All species & ages
Most common in grazing animals (sometimes humans)

Question 3

Clostridial gas gangrene diseases

Answer 3

• Blackleg
• Malignant oedema
• Braxy
• Köves disease
• Infectious necrotic hepatitis (“black disease”)
• Bacillary haemoglobinuria

Question 4

Clostridial toxaemic diseases

Answer 4

• Necrotic enteritis of chickens
• Lamb dysentery
• Struck/ Swine enterotoxaemia/ Necrotic enteritis of chickens
• Pulpy kidney disease
• Ulcerative enteritis of chickens

Question 5

Clostridial intoxications

Answer 5

• Tetanus
• Botulism
• Grass sickness (equine dysautonomia)

Question 6

Blackleg

Pathogen + susceptibility

Answer 6

Clostridium chauvoei
(a, b, d, g)

Mainly ruminants (sometimes pigs)

Question 7

Braxy

Answer 7

Clostridium septicum

Usually young sheep

PO w frozen, soil-cont. feed -> damage to mucosa of abomasum -> bact. enters wall of abomasum

Question 8

Köves disease

Answer 8

Clostridium septicum

Pigs

Bact. enters damaged stomach wall

Question 9

Infectious necrotic hepatitis

Answer 9

Clostridium novyi B
(a-toxin)

Sheep

Gut (loss of integrity) -> blood -> liver -> focal infl. + necrosis

Question 10

Bacillary haemoglobinuria (red water disease)

Answer 10

Clostridium haemolyticum
(b-toxin: phospholipase C -> necrotoxic + haemolytic)

Mainly beef cattle (sometimes sheep)

Question 11

Clostridial b-toxin (phospholipase C)

Answer 11

Necrotoxic + haemolytic

Question 12

Anthrax

Pathogenesis

Answer 12

• PO ingestion of spores
• -> intestines –> bacterial prolif. –> local lesion –> bloodstream –> toxin prod. –> blocks resp. center
• Inhalation of spores
• Wound infection (malignant carbuncle formation)

Question 13

Malignant oedema

Pathogenesis

Answer 13

• Wound infection (shearing, castration etc.)

Carbohydrate fermentation + toxins –> acid + gas –> oedema, necrosis

Question 14

Blackleg

Pathogenesis

Answer 14

• PO infection → GI tract (erosions in mm of gut) → Blood → Muscles (microtrauma) → Replicates in muscles that have experienced microtrauma with circulation problems  anaerobic