Brachyspira

Question 1

What are the characteristics of Brachyspira?

Answer 1

• Spiral shaped
• Anaerobic, O₂ tolerant
• Several species
  
  • 3 are important pathogens

Question 2

What are the Pathogenic Species of Brachyspira?

Answer 2

• B. hyodysenteriae
• B. hampsonii
• B. pilosicoli
• Strong Hemolysis

Question 3

What are the nonpathogenic species of Brachyspira?

Answer 3

• B. innocens
• B. intermedia
• B. murdochii
• Weakly hemolytic

Question 4

How are B.hyodysenteriae infections diagnosed?

Answer 4

• Based on clinical signs, lesions, and isolation of spiral shaped organisms with strong hemolytic activity
• Confirmation by PCR or Fluorescent antibody technique
• Dark-field or phase contrast microscopy of colonic mucosal scapings
• Fluorescent in situ hybridization (FISH) with species-specific monoclonal antibody

Question 5

Where can B. hyodysenteriae be found?

Answer 5

• Both pathogenic and nonpathogenic species reside in the intestinal tract of swine
  
  • Also wild rats and mice

Question 6

What is the mode of infection of B. hyodysenteriae?

Answer 6

Ingestion

Question 7

What are the virulence factors of B. hyodysenteriae?

Answer 7

• Hemolysin
• LPS
• Flagella

Question 8

What are the antigenic characteristics of B. hyodysenteriae?

Answer 8

• Nine serovars based on LPS antigen

Question 9

What is the pathogenesis of B. hyodysenteriae?

Answer 9

1. enters colon
2. invades goblet cells, multiplies in the crypts of Lieberkuhn
3. Stimulates mucus production

• “Muchohemorrhagic colitis”
• Primarily affects grower/finisher pigs

Question 10

What are the clinical signs of B. hyodysenteriae infection?

Answer 10

• Fever (104-105F)
• Watery diarrhea with mucus
  
  • +/- blood
• Abdominal pain
• Dehydration
• Chronic cases:
  
  • Persistent diarrhea with dark feces
• “Black scours”

Question 11

What lesions are seen with B. hyodysenteriae infections?

Answer 11

• Confined to large intestine
• Mucosa covered by mucofibrinous exudate with blood
• Swollen mesenteric lymph nodes

Question 12

How are B. hyodysenteriae infections treated?

Answer 12

• Antibiotics in the feed/water
  
  • Lincomycin, Tylosin, Tiamuli*, Carbadox*, Virginiamycin
• AMR is common, AST is beneficial
• Recovered animals may become carriers

Question 13

What are the control measures for B. hyodysenteriae?

Answer 13

• Antimicrobial feed additives
• Depopulation and sanitation of the facility
• Restock with noninfected pigs

Question 14

What disease does B. hyodysenteriae and B. Hampsonii cause?

Answer 14

Swine Dysentery

Question 15

Is there a Vaccine for B. hyodysenteriae?

Answer 15

• Autogenous vaccine
• Not very effective

Question 16

What is B. pilosicoli?

Answer 16

• Relatively new species
• Morphological differences
• Disease is called Porcine Colonic Spirochetosis
• Affects:
  
  • Humans, primates, dogs, guinea pigs, etc.

Question 17

What are the clinical signs of B. pilosicoli?

Answer 17

• Diarrhea (grower/finishing pigs)
  
  • Not very mucoid
  • May be dark red/tarry appearance

Question 18

How is B. pilosicoli diagnosed?

Answer 18

• Fluorescent antibody technique targeting specific OMP or PCR assay based on 16s rRNA genes

Question 19

What is the treatment for B. pilosicoli?

Answer 19

• Tiamulin
• Carbadox