Lesson 4c: Listeria species

Question 1

Outbreaks of listeriosis often related to ?

Answer 1

silage feeding

Question 2

Ingestion of feed contaminated with L. monocytogenes result to?

Answer 2

1. septicaemia
2. encephalitis
3. abortion

Question 3

In pregnant animals, infection results in ?

Answer 3

transplacental transmission

Question 4

It is thought that L. monocytogenes, may penetrate via _________ when sheep are cutting or losing teeth. From this site, migration in cranial nerves is thought to be the main route of infection in neural listeriosis

Answer 4

dental pulp

Question 5

has the ability to invade both phagocytic and non- phagocytic cells, to survive and replicate intracellularly and to transfer from cell to cell
without exposure to humoral defence mechanism.

Answer 5

L. monocytogenes

Question 6

in listeriosis this 3 destroys the membranes of phagocytic vacuoles allowing Listeria to escape into the cytoplasm

Answer 6

1. cytolytic toxin
2. listeriolysin,
3. phospholipase enzyme

Question 7

In the cytoplasm _______ & _____ produced
by the organism, directs the formation of tail-like structures from host cellular microfilaments which aid the motility of the invading pathogens thereby inducing pseudopod-like projections which are taken up by adjacent cells and replicate infection.

Answer 7

Actin-polymerizing protein& (ActA)

Question 8

Another way of L. monocytogenes to survive within the hosts cell is by ?

Answer 8

inhibiting cell autophagy.

Question 9

is present as encephalitis, abortion, septicaemia or endophthalmitis in ruminants.

Answer 9

Bovine Listeriosis

Question 10

Clinical signs of bovine listeriosis :

Answer 10

for neural listeriosis (14-40 days) are
1. dullness
2. circling
3. tilting of the head
4. unilateral facial paralysis

Question 11

Tx of bovine listeriosis;

Answer 11

1. ampicillin
2. amoxicillin,
3. In combination with aminoglycosides

Question 12

the pathogenicity associated with?

Answer 12

intracellular replication

Question 13

Septicaemic listeriosis has how many days of incubation period?

Answer 13

2-3 days