72. Gangrene

Question 1

Summarise gangrene

Answer 1

Type of tisse death caused by lack of blood supply

• Gangraena sicca (dry)
• Gangraena humida ( wet)
• Emphysematosa ( gas gangrene)

Question 2

Gangraena sicca

Definition:
changes :
Affects:

Answer 2

Drying out the necrotic tissue
- No bacteria

Macroscopic changes:
* Shrunken
* Dark brown
* Hard as wood
* Recognisable tissue structure

Affects:
- Skin
- umblical cord
- foetus: Mummification

Question 3

Gangrena humida

Definition:
changes :
Affects

Answer 3

Necrotised area superinfected with saprophytic bacteria (proteolysis)
- Bacterial infection

Changes:
* Pulpy & soft
* Grey-black (H₂S + Hb
* Putrid smell
* Gases

Affects:
- oral cavity
-lungs
- uterus

Question 4

Emphysematosa

Answer 4

Gas- gangrene

• Clostridia
• Muscles
• Gas-oedema

Question 5

Gangrena humida: Specific diseases

Answer 5

• Blackleg-disease
• Malignant oedema (skin & muscles)

Question 6

emphysematosia

Diseases:
Agents:
produce:

Answer 6

• Blackleg disease
• Malignant oedema

Agents (Clostridium)
- C. chauvoei
- C. septicum
- C. histolyticum

Produce: exotoxin and co2

Question 7

Emphysematosa ( gas gangrene)

Answer 7

General effect of exotoxin

• Autointoxication
• Skeletal muscle: Myositis emphysematosa
• Stomach wall:
  
  • Swine: Gastritis emphyematosa
  • Lamb: Bradsot
• Liver: Hepatitis emphysematosa
  
  • Sheep: Infectious necrotic hepatitis
• Uterus: Metritis emphysematosa