101. Infectious necrotic hepatitis, bacillary haemoglobinuria caused by Clostridium haemolyticum.

Question 1

Occurrence and ethiology Of black disease

Answer 1

Occurrence:

• worldwide,
• summer-early autumn

x Etiology:

• C. novyi B
• Sheep: 1-4-year-old (sometimes cattle)
• Facultative - Parasite infection: liver fluke ʹ in background

Question 2

Pathogenesis and clinical signs of black disease?

Answer 2

Pathogenesis:

• endogen infection enters gut
• Æ liver
• Æ liver necrosis caused by liver flukes (other parasites)
• Æ focal necrosis
• Æ toxic effects from alpha toxin absorbed
• Æ DEATH

Clinical signs:

• Fast,
• depression,
• teeth grinding,
• labored breathing

Question 3

Pathology, diagnosis differentiation and prevention of Black disease?

Answer 3

Pathology:

• liver (necrotic foci, surrounded by a red ring
• Æ haemolysis, Hgb diffused),
• accumulation of thoracic and
• abdominalfluid (if over longer time)

Diagnosis:

• signs and PM lesions
• Detection of the agent:
• microscopy,
• IF,
• bacterium culture
• Detection of toxin

Differentiation:

• fasciolosis

Prevention:

• antiparasitic
• vaccine: anaculture/anatoxin

Question 4

Occurrence Ethiology and pathogenesis of red water disease?

Answer 4

Occurrence:

• America,
• Australia, (Europe)
• Cattle (mainly beef cattle),
• sometimes sheep

Etiology:

• C. hemolyticum
• (beta toxin: phospholipase C, lecitinase ʹ decomposes RBC/hemolysis)
• Habitat: gut

Pathogenesis:

• infection PO from soil
• liver(anaerobic)
• Endogen infection
• Predisposing factor: fasciolosis
• Phospholipase C: intravascular hemolysis > anemia, hemoglobinuria

Question 5

Clinical signs, Pathology, diagnosis, differentation and treatment/control of red water disease?

Answer 5

Clinical signs:

• sudden onset (sometimes without signs),
• fever,
• depression,
• increased HR/RR,
• red urine,
• hemoglobinuria,
• jaundice,
• anemia

Pathology:

• thin blood,
• hemorrhages,
• edema,
• liver necrosis,
• bloody blood fluids (abdominal, thoracic cavity),
• red urine in bladder

Diagnosis:

• epi ʹ clinical signs - PM lesions
• Detection of agent: bacterium culture, IF
• Detection of toxin

Differentiation:

1. anthrax,
2. anaplasmosis,
3. leptospirosis,
4. toxicosis

Treatment:

• penicillin,
• fluid,
• blood transfusion (not often fluid/blood in cattle)

Control:

vaccine (6 monthƐ͛ protection) & antiparasitic