Topic 89 - Lamb dysentery and struck (GREEN)

Question 1

What is lamb dysentery?

Answer 1

It is a worldwide, sporadic disease causing death in 1-2 week old lambs

Question 2

Causative agent for lamb dysentery

Answer 2

Clostridium perfringens B

Question 3

Aetiology of Clostridium perfringens

Answer 3

C. perfringens produces toxins, which are produced by 12 toxins! There are 4 main toxins and 8 auxillary toxins

There are 5 different types of Clostridum perfringens, A-E and these strains are divided by the basis of combinations of the main toxins

Question 4

Name the main toxins of Clostridium perfringens

Answer 4

Alpha
Beta
Epsilon
iota

Question 5

Diseases caused by Clostridium perfringens A

Answer 5

Mainly a human pathogen, causing gas gangrene and food poisoning

Question 6

Diseases caused by Clostridium perfringens B

Answer 6

Lamb dysentery

Question 7

Diseases caused by Clostridium perfringens C

Answer 7

Struck
Pig enterotoxaemia
Necrotic enteritis of poultry
Necrotic enteritis of humans

Question 8

Diseases caused by Clostridium perfringens D

Answer 8

Enterotoxaemia of sheep and goats = Pulp kidney disease

Question 9

Route of infection in case of Lamb dysentery

Answer 9

Faeces
Environment, infected with poor hygiene
Teats can carry the infection

Question 10

Toxin produced by the causative agent of Lamb dysentery

Answer 10

Beta

Trypsin sensitive This means that the bacteria is only effecive the first two weeks due to the physiological trypsin inhibition

Question 11

Host and age susceptible for Lamb dysentery

Answer 11

Sheep
1-2 week old lambs

Question 12

Clinical signs in case of Lamb dysentery

Answer 12

1. Abdominal pain
2. Hunched back
3. Diarrhoea: foamy and brownish
4. Death will happen

Question 13

Post mortem lesions in case of Lamb dysentery

Answer 13

Limited to the small intestines mainly, there is a sharp start and ending where the lesions appear
1. Haemorrhagic and necrotic enteritis
2. Ulceration
3. Gas bubbles
4. Fluids and haemorrhages in the pericardium

Question 14

How to diagnose Lamb dysentery

Answer 14

Lamb dysentery can only be diagnosed with a direct smear with staining or with a detection of toxin

Question 15

Treatment of Lamb dysentery

Answer 15

Generally not possible

Question 16

Prevention of Lamb dysentery

Answer 16

1. Improving hygiene
2. Vaccine!
   The vaccine is given to ewes pregnant in their last trimester
3. Penicillin can be given to the ewes, and the piglet will get this through the milk

Question 17

What is struck disease?

Answer 17

It is a sporadic disease, occurring worldwide. Causing a fast death in sheep

Question 18

Causative agent for struck disease

Answer 18

Clostridium perfringens C

Question 19

Toxins produced by causative agent of struck disease

Answer 19

Alpha
Beta

Question 20

Pathogenesis of struck disease

Answer 20

1. Colonises in the mucosa of the rennet and small intestines
2. With predisposing factors, the Beta toxin is produced in large amount
3. We have a necrosis of the gut epithelium
4. There is a damage to the blood vessels
5. And there is an enterotoxaemia

Question 21

Predisposing factors for struck disease

Answer 21

Overeating
Change of diet
High protein and carbohydrate content

Question 22

Clinical signs for struck disease

Answer 22

Not very typical
1. Anorexia
2. Hunched back
3. Teeth grinding
4. NO diarrhoea
5. Fast death

Question 23

Post mortem lesions for struck disease

Answer 23

1. The rennet is filled with reddish fluid.
2. In the small intestine we see Haemorrhagic enteritis
   3. If the course is not too fast, we can see necrosis in the liver

Question 24

How to diagnose struck disease

Answer 24

Since the toxin is heat liable, detecting them is not too easy.
We can isolate the agent from the liver

Question 25

Treatment of struck disease

Answer 25

NO !! treatment

Question 26

Prevention for struck disease

Answer 26

1. Feed with high fibre content
2. Inactivated toxin vaccine