Approach to equine diarrhoea

Question 1

What are the two major functions of the equine hindgut?

Answer 1

Critical role in the storing and absorption of water
Site of fermentation of ingested fibre by bacteria and protozoal flora

Question 2

What is the definition of diarrhoea?

Answer 2

Symptom and NOT a disease
Increased water content in faeces
various severity and range of clinical presentation

Question 3

What is acute onset diarrhoea?

Answer 3

caused by infectious agents

Question 4

What causes acute onset diarrhoea in horses?

Answer 4

Salmonella, Clostridium, Coronavirus

Question 5

What causes acute onset diarrhoea in foals and weanlings?

Answer 5

Foal heat diarrhoea, Rotavirus, Rhodococcus equi, Lactose intolerance

Question 6

How does salmonelliosis cause acute equine diarrhoea?

Answer 6

Gram negative faculative anaerobe
Spread by the faecal-oral route
Faecal shedding varies by group and the method of detection

Question 7

What are the clinical signs of subclinical salmonelliosis?

Answer 7

None/ Non-pathogenic

Question 8

What are the clinical signs of mild salmonelliosis?

Answer 8

Fever, anorexia, depression, diarrhoea, rapid recovery

Question 9

What are the clinical signs of acute enterocollitis salmonelliosis?

Answer 9

Fever, anorexia, Depression, Diarrhoea, Colic
Gastric reflux

Question 10

What are the clinical signs of bacteraemia salmonelliosis?

Answer 10

Endotoxaemia
Meningitis, septic arthritis, osteomyelitis

Question 11

How would you diagnose salmonelliosis?

Answer 11

Bacterial culture, Faecal PCR, Lateral flow test

Question 12

What is clostridiosis?

Answer 12

Gram positive, anaerobic spore forming bacteria
spread via the faecal-oral route
Opportunistic pathogen of the GIT

Question 13

What is equine coronavirus?

Answer 13

Coronaviridae family group B enveloped ssRNA virus
spread by the faecal oral route

Question 14

What is larval cyathostominosis?

Answer 14

Clinical syndrome syndrome caused by mass emergence of encysted cyathostominlarvae from the large intestinal walls
Faecal testing is not reliable due to the larvae being encysted
Serum ELISA test

Question 15

How does carbohydrate overload occur?

Answer 15

CHO are digested in the small intestine
When ingested too much, CHO overflows into the large intestine
too many VFA’s and lactic acids lower the luminal pH
Normal flora disturbance
Pathogenic bacterial overgrowth

Question 16

What NSAIDS are routinely used for equine diarrhoea?

Answer 16

phenylbutazone, Flunixin, Meloxicam, Forocoxib

Question 17

What is the clinical impact of NSAID toxicity?

Answer 17

Equine gastric ulcer syndrome
Right dorsal colitis

Question 18

How would you treat NSAID toxicity?

Answer 18

Misoprostal
Sucralfate

Question 19

What is lawsonia intracellularlis?

Answer 19

Obligate intracellular gram negative bacteria
also an issue in the pig industry
causes proliferation of the crypt epithelial cells in the intestine

Question 20

What is the epidemiology of lawsonia intracellularis?

Answer 20

• Weanling and young yearlings (4 - 7 months most common)
• Seasonality: August to February
• Rabbits and rats: maybe reservoir/amplifier host

Question 21

How do you diagnose lawsonia intracellularis?

Answer 21

Haematology and Biochemistry
* Neutrophilia +/- elevated fibrinogen, SAA
* Hypoproteinemia, hypoalbuminemia
* Ultrasonography
* Thickened Small Intestine
* Faecal PCR
* Low sensitivity: intermittent shedding
* Serum ELIZA
* High sensitivity

Question 22

What are the three main problems in acute onset diarrhoea?

Answer 22

Dehydration
Protein loss
SIRS

Question 23

What is hypoalbuminaemia?

Answer 23

Protein loss from the gastrointestinal tract
Peripheral oedema, intestinal wall oedema, pulmonary oedema

Question 24

What is systemic inflammatory response syndrome?

Answer 24

Exaggerated defence response to inflammation throughout the whole body

Question 25

What causes chronic diarrhoea?

Answer 25

Inflammatory bowel disease
Lymphoma
Sand enteropathy