GI - equine diarrhoea

Question 1

Where does diarrhoea always originate from in horses?

Answer 1

Large intestine

Question 2

How much fluid enters the GI tract and is absorbed in the LI in 24 hours in a horse?

Answer 2

100L / 24 hours

Question 3

What is the term for bowel inflammation?

Answer 3

Colitis

Question 4

What are the 3 main mechanisms of diarrhoea from inflammation in horses?

Answer 4

Malabsorption
Increased secretion
Decreased transit time

Question 5

What does GIINANDDTONIICC stand for?

Answer 5

Genetic
Infection
Inflammation
Neurologic
Autoimmune
Nutritional
Developmental
Degenerative
Trauma
Ormonal (hormonal)
Neoplastic
Iatrogenic
Idiopathic
Cardiovascular
Chemical and toxic

Question 6

What are the main differentials of chronic colitis?

Answer 6

Chronic salmonellosis
Parasites - strongyles, cyathostomes
Sand eating
Inflammatory bowel disease
Neoplasia - lymphoma
NSAIDs

Question 7

What are the main differentials for acute colitis?

Answer 7

Salmonella, clostridia
Cyathostomes
Rotavirus - foals
Nutritional - diet change
Idiopathic
NSAIDs

Question 8

What is the most common cause of acute diarrhoea?

Answer 8

Idiopathic - most acute colitis

Question 9

What tests should you do in diarrhoea cases to assess dehydration?

Answer 9

Heart rate - skin tent doesnt work
Can do PCV/TP in lab

Question 10

What test can you do for protein lost?

Answer 10

Total proteins and albumin

Question 11

What tests should you do to find the cause of the diarrhoea?

Answer 11

Faecal sample - for bacteriology and egg count (for strongyles)
Biopsy - rectal or intestinal
Abdominoparacentesis
Abdominal ultrasound

Question 12

What can you evaluate for on a GI biopsy?

Answer 12

IBD
Neoplasia
Culture - salmonella
Encysted cyathostomes

Question 13

When should you do an intestinal biopsy? How do you do it?

Answer 13

In chronic cases if rectal biopsy was unrewarding - not common
Standing or GA - laparoscopy or laparotomy

Question 14

What is an abdominoparacentesis?

Answer 14

Belly tap

Question 15

What can you evaluate for on abdominoparacentesis?

Answer 15

Neoplasia - lymphoma, SCC
Inflammatory cells - IBD

Question 16

How do you treat chronic diarrhoea?

Answer 16

Horse usually stable so reach diagnosis then treat the cause

Question 17

How do you treat dehydration due to acute diarrhoea?

Answer 17

Make a fluid plan
IV fluids
Monitor

Question 18

How do you treat electrolyte and acid base imbalance in horses with acute diarrhoea?

Answer 18

Feed
Hydrate
Then spike fluid bags

Question 19

How do you treat hypoproteinaemia in horses with acute diarrhoea?

Answer 19

Plasma transfusion
(expensive)

Question 20

How do you treat endotoxaemia in horses with acute diarrhoea? What are the risks?

Answer 20

Flunixin - anti-endotoxic drug
Can cause colitis itself - balance risk of laminitis with risk of increasing colitis
Polymyxin B - binds LPS

Question 21

How do you treat bacteraemia/bacterial overgrowth in horses with acute diarrhoea?

Answer 21

If sick/toxic give penicillin, gentamycin, metronidazole
Take faecal and blood culture

Question 22

What is transfaunation?

Answer 22

Filter faeces from a healthy horse from the sick horses hone environment
Then nasogastric tube it several times

Question 23

What drugs can you give to encourage blood flow to the colon wall in horses with acute diarrhoea?

Answer 23

Prostaglandin agonists:
Oral sucralfate
Oral misoprostal

Question 24

What parasite causes massive inflammatory reaction, severe diarrhoea and often death in horses when they all emerge at once?

Answer 24

Cyathostomes

Question 25

What do cyathostomes look like?

Answer 25

Small redworm

Question 26

Where do the cyathostomes encyst? For how long?

Answer 26

Encyst in the large intestinal mucosa for 2-3 years

Question 27

How do you treat cyathostomiasis?

Answer 27

Moxidectin - be careful of inflammation from dead worms causing colitis Concurrent corticosteroids to reduce inflammation

Question 28

What worm parasite affects foals through dams milk causing diarrhoea 6 months later?

Answer 28

Strongyloides westeri

Question 29

What are the 4 clinical syndromes for salmonella in horses?

Answer 29

Latent/active carrier Depression, fever, anorexia, neutropenia but no diarrhoea or colic Acute enterocolitis with diarrhoea Septicaemia with/without diarrhoea

Question 30

How is salmonella spread?

Answer 30

Faeco-oral transmission Persists in environment

Question 31

What are the signs of acute enterocolitis due to salmonella in horses?

Answer 31

Fever, anorexia Endotoxaemia - shock, laminitis, thrombophlebitis Pink gums Diarrhoea - 24-48 hours after pyrexia Dehydration Colic

Question 32

When should you isolate a horse under suspicion of salmonella?

Answer 32

If it has any two of Pyrexia Depression Diarrhoea Leukopenia

Question 33

What is the prognosis of salmonella?

Answer 33

Need aggressive treatment - can be complications, become carriers, develop chronic salmonellosis Poor if persists more than 4-5 weeks

Question 34

What can trigger clostridia infection in horse GI tract?

Answer 34

Antibiotic administration

Question 35

Are clostridia normally found in the gut?

Answer 35

Yes, but not those producing enterotoxin

Question 36

What does lawsonia intracellularis cause in horses? When?

Answer 36

Proliferative protein-losing enteropathy in small intestine, diarrhoea

Question 37

How does lawsonia intracellularis cause diarrhoea in horses?

Answer 37

Alters nutrient absorption and fluid secretion by disrupting villi and stopping epithelial cells maturing into absorptive cells

Question 38

At what age does lawsonia intracellularis affect horses?

Answer 38

At weaning - 4-6 months old foals

Question 39

What is seen on ultrasound in lawsonia intracellularis infection?

Answer 39

Marked thickening and oedema of intestinal wall

Question 40

How do you treat lawsonia intracellularis?

Answer 40

Supportive treatment and plasma infusion Doxycycline - orally

Question 41

Where does NSAID induced colitis occur in the horses body?

Answer 41

Right dorsal colitis

Question 42

What are the clinical signs of NSAID induced colitis?

Answer 42

Anorexia, lethargy Colic Diarrhoea Protein losing enteropathy - ventral oedema

Question 43

How do you treat NSAID induced colitis?

Answer 43

Stop NSAIDs Analgese with opioids and buscopan, paracetamol maybe Treat colitis

Question 44

What can cause antibiotic induced colitis in horses that havent been given antibiotics themselves?

Answer 44

Dams ingesting foals erythromycin when they clean their face/butt

Question 45

What bacteria tends to overgrow in antibiotic induced colitis?

Answer 45

Clostridia

Question 46

What are some causes of IBD in horses?

Answer 46

When get excited When on haylage Spectrum of conditions

Question 47

How do you diagnose IDB in horses?

Answer 47

Ultrasound Peritoneal fluid sample - inflammatory cells Biospy if these fail

Question 48

How do you treat IBD?

Answer 48

Corticosteroids - pred ? Resection ? Short fibre diet ? Yeasacc

Question 49

What causes 'foal heat' diarrhoea in foals?

Answer 49

Change in GI function

Question 50

What is a common virus which causes diarrhoea in foals?

Answer 50

Rotavirus

Question 51

What is the most common bacterial cause of diarrhoea in foals up to 2 weeks old?

Answer 51

Gastroenteritis - failure of passive transfer

Question 52

What is the most common bacterial cause of diarrhoea 3 months old plus in foals?

Answer 52

Rhodococcus

Question 53

How can you correct hypoalbuninaemia in horses?

Answer 53

Blood plasma

Question 54

What does a high heart rate indicate in a horse?

Answer 54

Pain Dehydration Endotoxaemia

Question 55

What is the treatment for a horse with mild diarrhoea who doesnt seem systemically ill?

Answer 55

Transfaunation Maybe biosponge