Neonatal Diarrhea

Where is the majority of water absorbed?

Jejunum and ileum

Where does the horse have significant absorption?

Colon

What are the mechanisms of diarrhea?

Malabsorption

Hypersecretion

Hypermotility

What do coronavirus and rotavirus attack?

Tips of the villi

What does parvovirus attack?

Crypts of villus

What is the pathogenesis of bovine viral enteritis?

Multiplication in villous intestinal epithelial cells

Fecal oral transmission

Describe bovine enteric CoV

Common and often involved with other agents

What can cause fibrinonecrotizing colitis?

Bovine enteric CoV

What are the group of bovine rotaviruses?

A B or C

T/F bovine rotavirus is often subclinical?

True

T/F bovine rotavirus causes colitis?

False

What is the pathogenesis of piglet enteritis?

Viral infection of villar tip epithelium

Necrosis of epithelium at tips

Villus atrophy

Healing by adjacent epithelium and by crypt hyperplasia

Villus fusion

What is the pathogenesis of Cryptosporidium parvum?

Protozoa colonize villi

Smaller blue dots are along villi surfaces

What is the signalment for Crypto?

1-4 weeks of age with malabsorption and hypersecretion diarrhea

T/F co-infection is common with Crypto?

True

How can you diagnose Crypto?

Small blue dots on top of villi on histology

When does Cystoisospora suis affect pigs?

5-6 days

What is the pathogenesis of Cystoisospora suis?

Feces

Rapid sporulation of C. suis in environment

Ingested

Replicates in villus epithelium

Necrosis of epithelium

Villous atrophy, necrosis, erosion, ulceration, fibrin

Malabsorption and effusive diarrhea

What kind of diarrhea does Cystoisospora suis cause?

Malabsorptive and effusive

If you see fibrinonecrotic enteritis in a 6 day old pig what should you suspect?

Cystoisospora suis

What is required for E. coli to cause a disease?

Attachment and toxin production must be present

T/F E. coli causes villus atrophy?

False

What do you have to put on an exam when talking about E. coli being a causative agent?

Toxigenic or ETEC must be stated

What does chyle seen grossly tell you about the intestines?

There is still absorption occurring (no villus atrophy)

What are the mechanisms of diarrhea?

Malabsorption

Hypersecretion

Exudation

Hypermotility

What causes malabsorption diarrhea?

Osmotic diarrhea in the small intestine

What causes hypersecretion diarrhea?

Net efflux of food and electrolytes independent of permeability changes or absorptive capacity

T/F hypersecretion has a structurally intact mucosa?

True

What is an exudative diarrhea?

Increased capillary pressure or epithelial permeability

T/F hypermotility diarrhea is a common problem in domestic animals?

False

What causes swine viral enteritis?

Transmissible gastroenteritis virus

Porcine epidemic diarrhea virus

Porcine delta coronavirus

Swine acute diarrhea syndrome

Swine rotavirus group A

What is the pathogenesis of swine viral enteritis?

1. Fecal oral transmission

2. Multiply in villous intestinal epithelial cells

3. Villous atrophy

Describe TGE (transmissible gastroenteritis virus)?

Coronavirus common in suckling or nursing pigs. Eradicated by vaccines basically

Describe PED (porcine epidemic virus)

TGE like, not detected by TGE moleclular tests

Describe PDCoV

Similar to TGE, detected in wake of PED, less virulent

Describe rotavirus

Subclincial usually, severity depends on dose, age, and immunity

What is a cause of villus atrophy with an intact proliferative compartment and primary increased rate of lass of villar epithelium?

Coronavirus and rotavirus

What is a cause of villus atrophy with an intact proliferative compartment and a primary crypt hyperplasia?

Chronic coccidial infection

What is required for E. coli to be virulent?

Have pili and toxins

What is F4 (K88)?

Adhesion factor for pig E. coli

What is F5 (K99)?

Adhesion factor for calve E. coli

Why do F4 and F5 pili binding go away shortly after birth in calves and pigs?

The receptors are shed once the animal ages a few days

What E. coli pili is most common in nonneonates?

F18

What are the heat labile toxins?

LT1 and LT2

What are the heat stabile toxins?

STa and STb

T/F ETEC causes villous atrophy?

False

What is the pathogenesis of E. coli edema disease?

1. STEC serotypes O138, 139, and 141

2. Colonize by F18 fimbriae

3. STx2E toxin

4. Circulates in blood

5. Direct vascular injury/angiopathy, edema

What is an example of enterotoxemia?

E coli edema disease

What toxin causes E coli edema disease?

STx2E

How does E. coli that causes edema disease colonise?

F18

T/F E. coli edema has diarrhea?

False

How are C. perfringes typed?

Based on toxins

What toxin does C. perfringes type C produce?

Beta-toxin

What toxin does C. perfringes produce?

Alpha-toxin

What inactivates Beta toxin from C. perfringens?

Trypsin

Why is C. perfringes type C seen in neonates?

It produces Beta toxin which is inactivated by trypsin, which neonates do not have

What do all C. perfringes toxins do?

Cause necrosis and hemorrhage and emphysema

Necrosis and hemorrhage in a young animal points you to what?

C. perfringes

What is the pathogenesis of C. perfringens?

1. C. perf is a normal inhabitant

2. Microbiome alteration

3. Overgrowth of C. perf

4. Elaboration of toxins

5. Necrosis and hemorrhage

What toxins does C. difficile make?

A and B

What does C. difficile do?

Diarrhea and fibrinous colitis in neonatal and older pigs

T/F for both Clastridium and E. coli you have to confirm presence of bacteria and toxins before disease?

True

What is the pathogenesis of Salmonella?

1. Fecal-oral route

2. Colonize intestinal epithelium

3. Effector proteins

4. Secretory diarrhea and epithelial necrosis

5. Fibrinonecrotizing enteritis

If you see fibrinonecrotizing enteritis, what do you think?

Salmonella

T/F you can usually diagnose Salmonella with just presence of it, not toxin production?

True