Infectious Diseases of the Intestines

Question 1

what makes up the digestion at the brush border in the small intestine?

Answer 1

carbohydrases
peptidases

Question 2

how do intestinal viruses cause disease?

Answer 2

infect certain cells and blow them up

Question 3

what are the main viruses that impact the intestinal tract?

Answer 3

rotaviruses
coronaviruses
parvoviruses

Question 4

what does loss of the mucosal barrier lead to?

Answer 4

toxemia/sepsis

Question 5

what are the possible locations of gastrointestinal tract lesions?

Answer 5

damage to villi: enterocyte injury
crypt injury
altered microvilli
injury to lamina propria, submucosa, and deeper

Question 6

what are the types of gastrointestinal tract lesions?

Answer 6

inflammation
proliferative
necrotizing processes
functional alterations
lymphangiectasia
disorders of innervation

Question 7

what does parvovirus damage?

Answer 7

crypt epithelium

Question 8

what does Mycobacterium avium subsp paratuberculosis cause?

Answer 8

johne’s disease: thickened ileum due to granulomatous inflammation
macrophages expand lamina propria and submucosa

Question 9

what do rotaviruses cause histologically?

Answer 9

shortening and fusion of villi: jejunum and ileum

Question 10

which coronoviruses do pigs get?

Answer 10

transmissible gastroenteritis virus
porcine epidemic diarrhea virus

Question 11

parvovirus requires the host cells to be in _____________________

Answer 11

mitotic division

Question 12

what does bovine viral diarrhea virus cause histologically?

Answer 12

ulcers throughout gastrointestinal tract: over peyers patches
lymphoid depletion

Question 13

does enterotoxigenic E. coli cause lesions?

Answer 13

no

Question 14

who does enterotoxigenic E. coli affect?

Answer 14

neonates: piglets and calves

Question 15

where does shiga toxin producing E. coli impact?

Answer 15

spiral colon mesentery
gastric submucosa
eyelids
brain (neurological signs)

Question 16

who does shiga toxin producing E. coli affect?

Answer 16

post-weaning swine: 6-14 weeks

Question 17

what does Clostridium perfringens cause?

Answer 17

necrohemorrhagic enteritis in all species

Question 18

what toxin does Clostridium perfringens type D secrete?

Answer 18

epsilon toxin: damage to epithelial cells

Question 19

which animals are usually affected by Mycobacterium avium subsp paratuberculosis?

Answer 19

ruminants older than 2 years

Question 20

where are lesions from Mycobacterium avium subsp paratuberculosis?

Answer 20

ileum
cecum
proximal colon
ileocecal valve

Question 21

where do Brachyspira hyodysentereriae and Brachyspira pilosicoli impact?

Answer 21

cecum
colon

Question 22

which cells does Lawsonia intracellularis have an affinity for?

Answer 22

crypt cells

Question 23

which species are affected by Lawsonia intracellularis?

Answer 23

pig
horse
hamster
rabbit
ferret

Question 24

what are some fungal, fungal-life, and algal diseases of the intestine?

Answer 24

Histoplasma capsulatum
pythiosis: Pythium insidiosum
prototheca

Question 25

where does Pythium insidiosum impact in the gastrointestinal tract?

Answer 25

stomach small intestine large intestine

Question 26

what are some protozoal diseases of the intestines?

Answer 26

Eimeria/Isospora (coccidiosis) Cryptosporidium sp

Question 27

what are the gross lesions in severe coccidiosis?

Answer 27

hemorrhagic and necrotic, except in sheep and goats

Question 28

what are lesions like in sheep/goats with coccidiosis?

Answer 28

nodular, proliferative (hypertrophic crypt-villus units)

Question 29

where does Cryptosporidiosis live?

Answer 29

within brush border small intestine more than large intestine

Question 30

what are ascarids?

Answer 30

large worms in small intestine

Question 31

where do hookworms inhabit?

Answer 31

small intestine

Question 32

where do whipworms inhabit?

Answer 32

cecum +/- colon

Question 33

where do small strongyles in horses inhabit?

Answer 33

cecum colon

Question 34

how does digestion in the lumen of the small intestine occur (as apposed to the brush border)?

Answer 34

pancreatic enzymes bile

Question 35

what is typhlitis?

Answer 35

inflammation of cecum

Question 36

what kills animals with enteritis/colitis/typhlitis/proctitis?

Answer 36

dehydration loss of mucosal barrier: toxemia/sepsis

Question 37

what is proctitis?

Answer 37

inflammation of the rectum

Question 38

why is diarrhea more life-threatening for young animals?

Answer 38

slower turnover: losing fluids longer

Question 39

how do infectious diarrheas cause diarrhea?

Answer 39

some get into cells others make exotoxins others make secretory toxins

Question 40

are bacteria more important in large or small animals?

Answer 40

large animals

Question 41

what does damage to crypt epithelium lead to?

Answer 41

more severe maldigestion/malabsorption +/- exudation of blood, serum, inflammatory cells diarrhea

Question 42

what do rotaviruses produce?

Answer 42

secretory toxin: NSP4

Question 43

do rotaviruses have high or low mortality?

Answer 43

low mortality

Question 44

where do coronaviruses attack?

Answer 44

villi jejunum, ileum, colon

Question 45

what does shiga toxin producing E. coli cause?

Answer 45

edema disease: post-weaning pigs

Question 46

does enterotoxigenic E. coli cause lesions?

Answer 46

no

Question 47

is diarrhea or significant mucosal disease typical with shiga toxin producing E. coli?

Answer 47

no

Question 48

what cells do Salmonella sp survive inside?

Answer 48

enterocytes M cells macrophages

Question 49

what does acute salmonellosis look like in the intestines?

Answer 49

fibronecrotizing and hemorrhagic enteritis

Question 50

what does chronic salmonellosis look like in the intestines?

Answer 50

button ulcers

Question 51

how do Clostridium perfringes and C. difficile cause disease?

Answer 51

produce toxins: kill everything they encounter (epithelial cells, vasculature)

Question 52

where do Eimeria and Isospora (coccidia) impact?

Answer 52

small intestine large intestine in cattle

Question 53

what are severe lesions like of coccidiosis?

Answer 53

hemorrhagic and necrotic sheep/goats different