La Medicine Ii -- Foal Diarrhea

Front 1

What is foal heat diarrhea?

Back 1

-- mild, self-limiting diarrhea

-- occurs between 8-14 days of age

-- foals are clinically normal

Front 2

Why is it called foal heat diarrhea? What is the suspected cause?

Back 2

-- coincides with first pospartum estrus of mare

>> correlation, not causation

-- due to physiologic changes in foal's GI tract

-- occurs in orphan foals, too

Front 3

Treatment for foal heat diarrhea?

Back 3

-- no treatment usually necessary

-- keep clean, prevent scalding

Front 4

What is the most common infectious cause of diarrhea in neonatal foals? It causes up to ___% of all diarrhea cases in foals.

Back 4

-- rotavirus

-- 50% of diarrhea cases

>> high morbidity, low mortality

Front 5

Predisposing causes of rotaviral enteritis?

Back 5

-- overcrowding

-- poor hygiene

Front 6

Why is rotavirus good at causing outbreaks and becoming an endemic problem on some large farms?

Back 6

-- it survives well in the environment

>> need virocidal disinfectants

Front 7

Pathophysiology of rotavirus infection? What does this result in?

Back 7

-- virus invades the small intestine

-- absorptive cells are lost

-- brush border enzyme production disrupted

-- villous atrophy

-- proliferation of crypt cells

>> malabsorption

>> maldigestion

Front 8

One supportive medication that may help foals with malabsorption/maldigestion due to rotavirus?

Back 8

-- lactaid

Front 9

Rotavirus causes what kind of diarrhea? This results in what for the foal?

Back 9

-- profuse, watery diarrhea

-- dehydration

-- electrolyte distrubances

-- acid/base disturbances

Front 10

Death from rotavirus occurs due to? Thus, what treatment is important?

Back 10

-- hypovolemic shock

-- important to give IV fluids with supportive care

Front 11

Most foals with rotavirus improve when?

Back 11

-- improve within 3-5 days, up to 2 wks

Front 12

Diagnosis of rotavirus?

Back 12

-- PCR of feces

-- EM

-- ELISA

-- latex agglutination test

Front 13

Prevention of rotavirus infection?

Back 13

-- vaccination (big farms with endemic problems)

-- isolation

-- hygiene/biosecurity

-- disinfect equipment

>> virocidal, follow mixing instructions

>> phenolic compounds effective

Front 14

Salmonella targets foals of what age?

Back 14

-- < 30 day old foal

Front 15

With salmonella, ______ _____ occurs before _____ develops.

Back 15

-- septic shock occurs before diarrhea

Front 16

Clinical signs of salmonella?

Back 16

-- septic shock before diarrhea

-- obtunded

-- severe abdominal pain

-- profuse watery diarrhea

-- endotoxemia

Front 17

Laboratory findings with salmonella?

Back 17

-- acidemia, neutropenia, leukopenia, hypovolemia

Front 18

Diagnosis of Salmonella?

Back 18

-- PCR

-- blood culture (fresh sample)

-- may need to test mares (carriers/shedding)

Front 19

Species of clostridia that affect foals?

Back 19

-- C. difficile

-- C. perfringens type A, B, and C

Front 20

Most common type of clostridium that infects foals?

Back 20

-- Type A

Front 21

Signs of Clostridium infection?

Back 21

-- peracute death without diarrhea

-- severe diarrhea that lasts for days to weeks

>> can be hemorrhagic

-- bowel perforation and peritonitis

Front 22

Why are foals susceptible to clostridia?

Back 22

-- flora has not established itself in the foal

>> Clostridial organisms proliferate

Front 23

Pathogenesis of Clostridium infection?

Back 23

-- toxins are released

-- damage enterocytes

-- damage entire villus

-- serum exudation and hemorrhage

Front 24

Diagnosis of Clostridial infection?

Back 24

-- PCR for toxin producing genes

>> lots of normal foals have clostridia

>> need proof of toxin

>> e.g. alpha and beta pore-forming toxins

Front 25

Treatment of clostridium infection?

Back 25

-- metronidazole

-- often unrewarding

Front 26

Prevention of clostridial infection?

Back 26

-- consider vaccinating mares?

>> bovine vx, use caution

-- probiotics on farms w/ endemic clostridium

>> try to keep clostridium in check

-- good hygiene pre-foaling

>> wash mare's teats to dec. transmission

Front 27

Rhodococcus equi most often causes what kind of infection?

Back 27

-- respiratory infection
>> lung most common site in foals

-- uveitis, joint effusion

-- occasionally causes diarrhea

-- necrosis of lymph nodes and peyer's patches

Front 28

Isolation of rhodococcus equi in feces is diagnostic. T/F?

Back 28

-- false

-- not diagnostic, can be normal flora

Front 29

Equine proliferative enteritis is caused by what?

Back 29

-- Lawsonia intracellularis

Front 30

Lawsonia affects foals of what age?

Back 30

-- weanling foals

-- 6 mo or older

Front 31

Clinical signs of Lawsonia infection?

Back 31

-- anorexia

-- dependent edema

-- hypoproteinemia/hypoalbuminemia

-- lethargy

-- weight loss

-- fever, colic, diarrhea (less freq. observed)

Front 32

Lawsonia transmission?

Back 32

-- fecal oral transmission

Front 33

Diagnosis of Lawsonia?

Back 33

-- ultrasound: thickened SI walls

-- fecal culture, flotation

-- PCR

Front 34

Lab work with Lawsonia?

Back 34

-- CBC: hyperfibrinogenemia, neutrophilia, leukocytosis, hypoproteinemia

-- chem: hypoalbuminemia

Front 35

Treatment of Lawsonia? How long will it take for them to recover?

Back 35

-- abx: macrolides, tetracycline, doxycycline, chloramphenicol

-- crystalloid fluids, plasma

-- nutritional support

-- porcine vx (off-label)

-- weeks to recover

Front 36

Prevention of Lawsonia?

Back 36

-- vx

-- dec. stress

-- parasite control

-- antimicrobials

Front 37

Cryptosporidium pathogenicity _____.

Back 37

-- pathogenicity unclear

>> can be found in completely normal foals