Pasteurellaceae: Haemophilus and Histophilus

Question 1

Haemophilus and Histophilus are gram ______ bacteria.

Answer 1

Negative

[coccobacilli]

Question 2

True/False. Haemophilus and Histophilus are facultative anaerobes and opportunistic pathogens.

Question 3

What does it mean to say that Haemophilus is a fastidious organism?

Answer 3

Needs special factors and environmental conditions to grow

Requires 5-10% CO₂ for optimal growth

Question 4

What is Factor X? What kind of agar would you grow these haemophiles on?

Answer 4

Factor X is (Hemin-protoprophyrin IX) a component in the blood

These haemophiles are grown on blood agar because it contains Factor X

Question 5

What is Factor V? Which kind of agar do you grow these haemophiles on?

Answer 5

Factor V is NAD (nicotine adenine dinucleotide)

Use chocolate agar because it has both factors required for growth (X AND V)

Question 6

How does growth of Haemophilus with Staphylococcus happen?

Answer 6

Staphyloccous lyses red blood cells and supplies NAD (Factor V)

Satellitism growth around Staphylococcus colonies

Question 7

Which species does Haemophilus parasuis affect? What disease does it cause?

Answer 7

Pigs

Glasser’s disease

Key features of disease: polyserosistis, polysynovitis, meningitis

Question 8

How is Haemophilus parasuis transmitted?

Answer 8

Spread from sows to piglets at early stage of life

Question 9

How can you differientiate Haemophilus suis from Actionbacillus pleuropneumonia?

Answer 9

Hemolysis

CAMP +

Question 10

What is the main disease caused by Histophilus somni? Which species does it affect?

Answer 10

Bronchopneumonoia in feedlot cattle (shipping fever)

Question 11

Why was Histophilus somni removed from the Haemophilus family?

Answer 11

It does not need Factor X or V and can grow on blood agar

Question 12

What is the main virulence factor of H. somni?

Answer 12

Lipooligosaccharides (LOS)

Question 13

What other condition will you see with Histophilus somni and is pathognomic for H. somi infection?

Answer 13

Thromboemolic meningoencephalitis (TEME) - Sleeper syndrome

Question 14

What are other key lesions for Histophilus somni that you won’t see with Pasteurella or Haemophilus?

Answer 14

Necrotic laryngitis

Myocarditis (picture)

Abortion

Vulvitis, vaginitis, cervicitis, endometritis

Orchitis

Question 15

Which bacteria cause Fowl Coryza?

Answer 15

Avibacterium paragallinarum

[factor V dependent]

Question 16

What are the clincal signs of Fowl Coryza?

Answer 16

Swelling of infraorbital region, oculonasal discharge, swollen wattles and diarrhea

Question 17

Which bacteria resembles Pasteurella and can cause respiratory tract diseases in wild and domestic birds?

Answer 17

Ornithobacterium rhinotracheale

[resembles NAD-independent Actinobacillus paragallinarum]

Question 18

How can you control the spread of Fowl Coryza?

Answer 18

Prevention

All-in/all-out farm programs with sound management and isolation methods

“biosecurity for the birds”