Diarrhea of grow-finish and adult swine

Question 1

What are the two main diarrheic dz of adult swine?

Answer 1

1. necroproliferative enteritis

2. swine dysentery

Question 2

What is necroproliferative enteritis?

Answer 2

A group of prevalent ACUTE and CHRONIC conditions of widely differing clinical signs but ith a COMMMON UNDERLYING PATHOLOGY

Question 3

What are the three chronic manifestations of necroproliferative enteritis?

Answer 3

PIA–porcine intestinal adenomatosis
NE–necrotic enteritis
RI-regional enteritis

Question 4

What is PIA?

Answer 4

Porcine intestinal adenomatosis (proliferative enteropathy)

Question 5

What is NE?

Answer 5

Necrotic enteritis (coagulative necrosis of mucosa)

Question 6

What is RI?

Answer 6

regional ileitis (granulomatous inflammation, hypertrophy of muscle layers)

Question 7

Who gets the chronic manifestation of necroproliferative enteritis?

Answer 7

grower and finisher hogs

Question 8

Who gets the acute manifestation of necroproliferative enteritis?

Answer 8

finisher hogs and adults

Question 9

What is PHE?

Answer 9

an acute manifestation of necroproliferative enteritis

Proliferative hemorrhagic enteropathy–severe GIT hemorrhage

Question 10

How is necroproliferative enteritis transmitted?

Answer 10

fecal oral

Question 11

What is the pathogen responsible for necroproliferative enteritis?

Answer 11

lawsonia intracellularis

Question 12

When are animals exposed to lawsonia intracellularis (chronic form)

Answer 12

late nursery or early grower

Question 13

What is the incubation period of chronic necroproliferative enteritis

Answer 13

2-3 wks

Question 14

What are the clinical signs of chronic necroproliferative enteritis?

Answer 14

1. diarrhea (50%)
2. slow growth
3. weight loss
   (more severe signs associated with increasing mucosa/muscle layer involvement)

Question 15

What is the pathogenesis of chronic necroproliferative enteritis?

Answer 15

1. intracellular invasion of intestinal crypt cells (affintiy for immature)
2. proliferation of immature crypt cells (don’t mature)

Question 16

What is the consequence of proliferation of immature crypt cells in chronic necroproliferative enteritis?

Answer 16

hyperplastic–>adenomatosis
thickened mucosa (SI and colon)
hose-pipe gut (ileum)

Question 17

What are the lesions of porcine intestinal adenomatosis?

Answer 17

no necrosis, only mucosal proliferation mainly ileum

corrugated hyperplastic appearance. Homogenous diarrhea

Question 18

What area of the gut does lawsonia intracellularis most typically affect?

Answer 18

the ileum (less common colon and caecum)

Question 19

What area of the intestine does lawsonia intracellularis affect that swine dystentery (brachyspira) does not affect?

Answer 19

the ileum

Question 20

What are the lesions of necrotic enteritis?

Answer 20

necrotic membrane on the thickened intestine? may slough off

Question 21

What are the lesions of regional ileits?

Answer 21

smooth muscle hypertrophy occurs when the necrotic mucous membrane has sloughed away

Question 22

Is regional ileitis common or rare?

Answer 22

rare, most pigs die before this

Question 23

What is the progression through the types of chronic necroproliferative enteritis?

Answer 23

PIA–>NE–>RI

Question 24

What are the clinical signs of acute necroproliferative enteritis? (proliferative hemorrhagic enteritis)

Answer 24

1. anorexia
2. acute/peracute death
3. anemia
4. melena

Question 25

What is the pathogenesis of proliferative hemorrhagic enteritis?

Answer 25

Degeneration of epithelial cells, leakage of capillary beds | =>acute hemorrhage in upper SI

Question 26

What are DDX for PHE in young boars?

Answer 26

gastric ulcers | swine dysentery

Question 27

What animals are at risk for proliferative hemorrhagic enteritis?

Answer 27

older finisher hogs | gilts and boars (breeding)

Question 28

What are the lesions of PHE

Answer 28

dark digestd blood in colon. ileal serosa markedly corrugated.

Question 29

How is necroproliferative enteritis diagnosed?

Answer 29

1. gross pathology chronic: corrugated acute: blood/melena 2. stains for intracellular bacteria 3. IHC 4. PCR feces of tissue 5. serology--poor, low Ig NOT culture

Question 30

How is necroproliferative enteritis treated?

Answer 30

1. if PHE=medical emergency--parenteral antimicrobials | 2. water and feed products for herd treatment--more for chronic

Question 31

How is necroproliferative enteritis prevented?

Answer 31

Vaccination--vaccinate in nursery prior to exposure. Oral water soluble. No antimicrobials can be given 3 days before or after and no chlorine in water can put on feed, in mouth, in water

Question 32

How does necroproliferative enteritis vaccine work?

Answer 32

the attenuated live bacteria pass to the small intestine and colonize and induce active immune response

Question 33

What is swine dystenerry caused by?

Answer 33

brachyspira hyodysenteriae

Question 34

What are the features of brachyspira hyodysenteriae?

Answer 34

spirochete | strongly haemolytic

Question 35

What are the virulence factors of brachyspira hyodysenteriae?

Answer 35

1. hemolysins | 2. flagella--love mucus

Question 36

What pigs get brachyspira?

Answer 36

those >8weeks

Question 37

How is brachyspira transmitted?

Answer 37

fecal oral

Question 38

Is brachyspira highly contagious?

Answer 38

yes

Question 39

How can brachyspira travel between farms?

Answer 39

via fomites

Question 40

Can brachyspira survive in the environment?

Answer 40

yes, long term survival

Question 41

Are there reservoirs of brachyspira?

Answer 41

yes, many animals e.g. mice (1yr). can survive in manure pits for 2 months. RODENT CONTROL AND SANITATION IMPORTANT

Question 42

What is the incubation period of brachyspira?

Answer 42

2-14d

Question 43

What are the clinical signs of swine dysentery?

Answer 43

``` MUCOHAEMORRHAGIC DIARRHEA 1. acute stage mucus and blood--FRANK BLOOD mucofibrinous exudate 2. chronic diarrhea without blood or mucus. similar to ileitis ```

Question 44

How does the blood in the diarrhea of swine with acute swine dysentery differ from that of pigs with PHE?

Answer 44

the blood is frank, rather than melena. Also lots of mucus

Question 45

What is the pathogenesis of swine dystentery?

Answer 45

unknwn

Question 46

What areas of the GIT does swine dystenery affect?

Answer 46

caecum and colon only

Question 47

What is the lesion of swine dysentery?

Answer 47

1. fibrinous necrotizine haemorrhagic typhlocolitis. 2. mucosa covered by mucus, fibrin, flecks of blood. 3. mesentery and large intestine wall edematous/congested 4. fibrinonecrotic pseudomembrane if chronic severe--unlikely

Question 48

How is swine dysentery diagnosed?

Answer 48

1. blood/blood tinged/mucoid diarrhea 2. lesions confined to caecum, colon, rectum 3. direct smears (feces, mucosa)--spirochaetes 4. strong beta hemolysis 5. PCR--ID species not serology

Question 49

How is brachyspira cultured?

Answer 49

on specialized blood agar, anaerobic??

Question 50

How is swine dysentery treated?

Answer 50

1. parenteral | 2. mass medication--high costs

Question 51

What is the long term control for swine dysentery?

Answer 51

1. depopulation 2. herd elimination by emptying and disinfecting nursery grow finish and eliminating reservoirs, medicating breeding stock (5-6x therapeutic dose) to stop shedding, then restocking with negative weaned pigs.

Question 52

Why can you not do load, close, expose with brachyspira hyodysenteriae?

Answer 52

because it survives for a long time in the environment

Question 53

Which diarrhea is chunky and which is smooth?

Answer 53

chunky--swine dysentery? | smooth--necroproliferative enteritis