Spore-Formers

Question 1

Why form Endospores?

Answer 1

Resistance to dessication, freezing, heating, Radiation, UV light, and chemicals.

Question 2

What are the important spore formers? What is their classification?

Answer 2

Both Gram positive rods.
Clostridium - Anaerobic
Bacillus - Aerobic

Question 3

Important Clostridium species (3)

Answer 3

C. perfringens, C. botulinum, C. tetani

Question 4

What diseases are the Clostridia related to? (3)

Answer 4

Enterotoxaemias, Intoxication, Histotoxic affects.

Question 5

C. Perfringens: How many types?

Answer 5

Five types (A-E) based on toxin production.

Question 6

C. perfringens mainly related to which diseases (3)…

Answer 6

Enterotoxaemias in sheep, Blackleg (in ruminants) and Necrotic Enteritis in Pigs and Poultry.

Question 7

C. perfringens Type A: which toxins?, causes…

Answer 7

Alpha toxin, Enteritis in Pigs and Chickens.

Question 8

C. perfringens Type B: which toxins?, causes…

Answer 8

Mainly Beta toxin, but also Epsilon. Enterotoxaemia in Sheep (Lamb Dysentery)

Question 9

C. perfringens Type C: which toxins?, causes…

Answer 9

Mainly Beta toxin.

Enterotoxaemia in Sheep (Struck), Necrotic Enteritis in Lambs and Piglets.

Question 10

C. perfringens Type D: which toxins?, causes…

Answer 10

Mainly Epsilon toxin.

Enterotoxaemia in Sheep (Pulpy Kidney)

Question 11

C. perfringens: What are it’s histotoxic effects?

Answer 11

Wound contamination. Spores contaminate traumatised tissue from the soil or faeces.

Question 12

C. chauvoei causes…

Answer 12

Blackleg in Ruminants. - Latent spores in muscle and liver, may be activated by trauma.

Question 13

C. novyi toxins causes…

Answer 13

Histotoxic wound infections in Rams (Big Head), and Black Disease following Fasciola Hepatica infestatio.

Question 14

C. botulinum: Why is it important?

Answer 14

Preventable by careful canning and treatment, Spores germinate in Anaerobic feed stuff. Ingestion of very poisonous Toxin.

Question 15

C. botulinum: How does the toxin work, what is the final outcome?

Answer 15

Botox blocks release of ACh at NMJ. This leads to Flaccid paralysis and Death.

Question 16

C. tetani: Where it it found, what does it cause?

Answer 16

‘Drumstick’ shaped Spores found in Soil or Faeces. Inoculated into Tissue. Causes Tetanus.

Question 17

C. tetani: How does the toxin work, what is the final outcome?

Answer 17

Release of Tetanospasmin. It blocks release of NT from inhibitory synapse, uncontrolled synapse. Tensing of muscles, Paralysis.

Question 18

Bacillus: Which species is important and why?

Answer 18

Bacillus anthracis - cause of Anthrax.

Question 19

Why is B. anthracis so important?

Answer 19

Produces a highly toxic exotoxin - Holotoxin. This causes death by causing systemic shock.

Question 20

B. anthracis: Holotoxin components (3)

Answer 20

(1) Oedema factor, (2) Protective factor (binding to receptor), (3) Lethal Factor

Question 21

Anthrax: Species, Route of Infection?

Answer 21

Affects mainly Sheep, Cattle and Horses. Spores enter usually via GIT (esp with spiny vegetation), gain entry to Blood.