Actinobacillus

Question 1

What facultative pathogen of pigs under 6 months of age needs to be cultured with S. aureus as a source of NAD?

Answer 1

Actinobacillus pleuropneumoniae

Question 2

What are the 2 types of Actinobacillus pleuropneumoniae and how do they differ when cultured?

Answer 2

Biotype 1: NAD dependent - no growth beyond diffusion zone of NAD (S. aureus)

Biotype 2: NAD independent - no limit to growth

Question 3

What are the 2 types of transmission for Actinobacillus pleuropneumoniae?

Answer 3

Pig to Pig: contact or aerosol

Stable to Stable: ventilation, regrouping, farmers

Question 4

What are the clinical signs associated with acute and hyperacute A. pleuropneumoniae infection?

Answer 4

Fibrinous pleuritis, hemorrhagic necrotizing pneumonia, respiratory distress

Question 5

What can be found on the lungs in chronic A. pleuropneumoniae infections?

Answer 5

Nodules

Question 6

Detection of carriers is critical in controlling outbreaks of A. pleuropneumoniae. How would you test pigs in the stable to see if they’re carriers?

Answer 6

PCR on swabs from the nose and tonsils

Question 7

T/F: pigs can be vaccinated against Actinobacillus pleuropneumoniae.

Answer 7

TRUE

Question 8

Antibiotics are administered in what ways for A. pleuropneumoniae?

Answer 8

IV or PO

Question 9

What kind of toxin does A. pleuropneumoniae produce?

Answer 9

APX

Question 10

Which Actinobacillus species is similar to A. pleuropneumoniae, but less severe, and found in the tonsils and vagina of carriers?

Answer 10

Actinobacillus suis

Question 11

What are the 2 subspecies of Actinobacillus equuli?

Answer 11

Haemolyticus

Equuli

Question 12

Which subspecies of Actinobacillus equuli has a horse reservoir?

Answer 12

subsp Haemolyticus

Question 13

Pigs and horses are reservoirs for what subspecies of A. equuli?

Answer 13

subsp Equuli

Question 14

What are the clinical signs of Actinobacillus equuli BEFORE septicemia?

Answer 14

Pneumonia
Pleuritis
Bronchitis

Question 15

Septicemia from A. equuli in foals leads to what?

Answer 15

Sleepy Foal Disease, enteritis, slimy pus

Question 16

Septicemia from A. equuli in adult horses causes what clinical signs?

Answer 16

Abortion, joint localization.

Question 17

T/F: both foals and adults can be treated successfully with abx after being infected by A. equuli.

Answer 17

FALSE: adults can be treated but antibiotic treatment in foals fails most of the time :-(

Question 18

What Actinobacillus species causes “wooden tongue” or “timber tongue” in cows, and sometimes stomatitis in horses?

Answer 18

Actinobacillus lignieresii

Question 19

Infection by Actinobacillus lignieresii is endogenic and can be found in the _________ of cattle, sheep and horses.

Answer 19

nasopharynx

Question 20

A. lignieresii infects what type of tissue?

Answer 20

Connective tissue (weak tissues)

Question 21

You arrive at a farm to discover one of the cows has granulomatous abscesses around the jawline with yellow pus and sulfur granules. In light of a recent surgical procedure, you are suspicious of Actinobacillus lignieresii. What could have caused this, how can you test for it, and how will you treat it?

Answer 21

Likely caused by surgical contamination.

Dx: microscopy of granules to see structure and look for Gram negative bacteria.

Tx: Surgical intervention and iodine based topicals

Question 22

What’s the prognosis like for Actinobacillus lignieresii?

Answer 22

Good only if caught early!

Relapse common.