Swine Dysentry

Question 1

What causes swine dysentry?

Answer 1

*Brachyspira hyodysenteriae.
* But can include other bacterial species such as B. piloscoli and B. intermedia.

Question 2

What does swine dysentry cause?

Answer 2

*Severe inflammation of large intestine
*Goblet cell hyperplasia
*Malabsorptive diarrhoea - contains blood + mucus

Question 3

What is swine dysentry most common in?

Answer 3

pigs from 12 to 75kg but severe cases occur occasionally in sows and their sucking piglets

Question 4

What is the incubation period of swine dysentry?

Answer 4

7-14days
can be as long as 60days

Question 5

How long can bacteria live in the environment?

Answer 5

up to 7 weeks in cold moist area
-dies in 2 days in dry warm area

Question 6

What are the clinical signs of dysentry in piglets?

Answer 6

• Severe acute dysentery
• Sloppy light brown faeces with or without mucous or blood.
• Loss of condition.

Question 7

What are the clinical signs of dysentry in weaners/growers?

Answer 7

• Sloppy diarrhoea, which stains the skin under the anus.
• Initially the diarrhoea is light brown and contains jelly-like mucus and becomes watery. May contain blood
• Twitching of the tail.
• Hollowing of the flanks with poor growth. Loss of condition
• Partial loss of appetite.
• Slight reddening of the skin.
• Becomes dehydrated.
• Gaunt appearance & sunken eyes.
• Sudden death may occur - mostly in heavy finishers.

Question 8

What is Brachyspira spp?

Answer 8

• Very resistant bacteria
• Bacteria invades intestinal pithelium- particularly in caecum and colon
• Produces toxins
• Leads to decreased reabsorption, and diarrhoea
• Risk of secondary infection

Question 9

How is Brachyspira spp transmitted?

Answer 9

• Pigs become infected through the ingestion of infected faeces.
• Spread is by carrier pigs that shed the organism in faeces for long periods. May enter farm this way
• Mechanically in infected faeces via equipment, contaminated delivery pipe of feed vehicles, boots or birds.
• It can be spread by flies, mice/ rats, birds and dogs.
• Stress resulting from change of feed may precipitate.
• Poor sanitation and wet pens enhance the disease.
• Overcrowding.

Question 10

How is Brachyspira spp diagnosed?

Answer 10

• This is based on the history
• The clinical picture
• Post-mortem examinations
• Gram-stained faecal or
  colonic smears (rules out
  other organisms)
• PCR of swabbed faecal
  material.
• Fluorescent antibody tests
  on faecal smears
• Isolation and identification
  of B. hyodysenteriae.

Question 11

How is brachyspira controlled?

Answer 11

• Biosecurity very important. Prevent entry and/ or spread
• Prevent access to slurry pits
• Control flies
• Strategic medication with lincomycin or tiamulin (NOT highly recommended but common abroad)
• Foot baths for farm personnel
• Reduce movement and handling of pigs
• Avoid overcrowding
• Isolate and quarantine incoming pigs

Question 12

How is Brachyspira spp controlled?

Answer 12

• Doxycyclin
• Carbadox * +
• Dimetridazole *.+
• Lincomycin *.
• Monensin *.+
• Ronidazole *.+
• Tiamulin *.
• Tylosin *.
• Valnemulin *
  (*very active + no available in conse countries)