Lecture 27 - GI/Liver Bacteriology 5

Question 1

what is unique about Lawsonia intracelullularis?

*hint: it is in it’s name

Answer 1

obligate intracellular pathogen

Question 2

what is the habitat for L. intracelullularis?

Answer 2

enterocytes mainly in pigs and foals

Question 3

how is L. intracelullularis spread?

Answer 3

excreted via feces

Question 4

summarize the pathogenesis of Lawsonia in steps

Answer 4

1. attach to enterocytes
2. internalized into cells
3. upregulate cell division
4. cause proliferative enteropathy
5. spread along intestinal mucosa leading to clinical sings

Question 5

immature enterocytes replace _____ and _____

Answer 5

goblet cells; absorptive cells

Question 6

If enterocytes outnumber goblet and absorptive cells what 3 things occur

Answer 6

1. more fluid loss
2. decreased absorption
3. lose of protein into lumen

Question 7

describe lawsonia in pigs

Answer 7

Porcine Proliferative Enteropathy

• high morbidity, low mortality
• chronic intermittent diarrhea to acute hemorrhagic enteropathy
• reduced weight gain
• finishing and weaned pigs

Question 8

describe lawsonia in foals

Answer 8

Equine Proliferative Enteropathy

• rapid weight loss, D+, colic, fever, edema
• affecting weanlings (<1 y/o)

Question 9

describe the progression of lawsonia in foals in 4 steps

Answer 9

1. protein loss into the intestine
2. low protein in blood
3. fluid leaks out into tissues
4. edema

Question 10

T/F: a hallmark of Lawsonia in horses would be thickened intestines on ultrasound

Answer 10

TRUE

Question 11

what diagnostics are available for lawsonia

Answer 11

1. US
2. scrapings
3. PCR

Question 12

T/F: if diagnosed with lawsonia, horses should be treated with tylosin and pigs should be treated with clarithromycin

Answer 12

FALSE - flip treatments

Question 13

T/F: a live vaccine for lawsonia is available to pigs

Answer 13

TRUE

Question 14

what is the habitat for Brachyspira

Answer 14

large intestine of animals, but can survive in the environment for long

Question 15

what enzyme assists Brachyspira’s tolerance to oxygen

Answer 15

NADH oxidase

Question 16

T/F: Brachyspira have flagella responsible for motility and penetration into mucus layer

Answer 16

TRUE

Question 17

T/F: brachyspira produces only hemolysin

Answer 17

FALSE - hemolysin AND cytotoxin

Question 18

T/F: Brachyspira does not penetrate beyond the intestinal epithelium

Answer 18

TRUE

Question 19

brachyspira causes what regarding pathogenesis

Answer 19

1. degeneration and inflammation of superficial mucosa
2. hypersecretion of mucus

Question 20

describe the clinical disease of B. hyodysenteriae in swine

Answer 20

Swine dysentery

• 6-12 weeks of age
• decrease app. and polydipsia
• D+ (first yellow and then bloody)
• large economic loss

Question 21

describe B. pilosicoli

Answer 21

affects birds, pigs, and humans

pig: chronic mucoid d+
poultry: d+, egg loss, increased mortality

Question 22

what are the diagnostics available for Brachyspira

Answer 22

1. cecal scrapings
2. culture (anaerobic, slow-growing)
3. PCR
4. species ID w/ biochemical testing

Question 23

how is brachyspira treated

Answer 23

antibiotic administration in water

Question 24

how is brachyspira controlled (3 ways)

Answer 24

1. improved hygiene/biosecurity
2. rodent control
3. depop. to remove carriers