Lecture 6: Approach to medical diseases of the equine large colon

Question 1

Diarrhea is an issue in which part of intestines

Answer 1

Large colon

Question 2

What are the top 10 differential diagnoses of equine colitis

Answer 2

1. Salmonella spp
2. Clostridia spp
3. Antibiotic induced
4. Potomac horse fever
5. Equine enteric coronavirus
6. Larval cyathostominosis
7. Blister beetle/cantharidin
8. NSAIDS
9. Sand colic
10. Carbohydrate overload

Question 3

How many negative test do you need to diagnosis clearance of salmonella

Answer 3

5 negative tests

Question 4

What is treatment for Potomac horse fever

Answer 4

Tetracycline and supportive case

Question 5

What is treatment for laraval cyathostominosis

Answer 5

Moxidectin and supportive care

Question 6

What type of feed is the blister beetle/cantharidin associated with

Answer 6

Alfalfa

Question 7

T or F: give oil to horses with blister beetle/cantharidin

Answer 7

F= will increase absoprtion of toxin

Question 8

What part of the intestines is most likely affected by NSAIDS

Answer 8

Right dorsal colon—> ulceration—> strictures in mucosa—> chronic colic

Question 9

What tests can be run to determine sand is present

Answer 9

Sand float

Question 10

What can be used to treat sand colic

Answer 10

Psyllium, oil

Question 11

What is a huge risk for carbohydrate overload

Answer 11

Laminitis risk

Question 12

What should you do to treat carbohydrate overload

Answer 12

Gastric lavage, activated charcoal, biosponge

Question 13

How do you diagnose impactions in equine large colon

Answer 13

Rectal palpation

Question 14

T or F: fever is present in simple impactions

Answer 14

False

Question 15

Case example: 13yr Gypsy Vanner with colic signs, depressed, bloated, T=103.1 P=56, R=28, hypermotile GI sounds, bright red mucous membranes
Rectal: everything in normal location, large colon filled with fluid, then exslosive diarrhea- what is your most immediate concern and what do you do next

Answer 15

Biosecurity- diarrhea is treated as infectious until proven otherwise
1. Referral
2. Isolate horse
2. Separate personnel handle this horse last
3. Foot baths

Question 16

Blood work results:
CBC: WBC decreased, HCT increased, platelets increased, neutrophils decreased, bands increased, lymphocytes decreased, fibrinogen increased

What does this tell you

Answer 16

dehydrated, acute inflammation, bands- immature neutrophils, fibrinogen- acute inflammation

Question 17

Blood work results:
Chemistry: decrease total protein, albumin increased indirect bilirubin, increase creatinine, decrease Na, Cl-

Answer 17

Losing protein to intestines, dehydrated, anorexia

Question 18

Arterial blood gas results:
PH: 7.2
PCO2- 40
PO2-95
HCO3-15.1
BEecf: -11.4
SO2- 99

What does this tell you

Answer 18

Uncompensated metabolic acidosis

Question 19

Test results;
Salmonella culture positive, clostridia positive, toxins negative, coronavirus negative, FEC 50epg

What is diagnosis

Answer 19

Salmonella colitis

Question 20

What is treatment plan for horse with salmonella colitis

Answer 20

1. IV fluids
2. Potassium added to fluids
3. Colloids- plasma and hetastarch
4. Banamine, polymixin B
5. Laminitis prevention- cryotherapy
6. Parental nutrition
7. Biosecurity

Question 21

What antibiotics do you want to give with severe neutropenia

Answer 21

Broad spectrum

Question 22

What antibiotics do you want to give for clostridal infection

Answer 22

Metronidazole

Question 23

What antibiotics do you want to give for Potomac horse fever

Answer 23

Tetracycline

Question 24

What could happen if you give tetracycline too fast

Answer 24

Pull out Ca2+—> horse can collapse

Question 25

Case example: horse is colicky, quiet, looking at abdomen. T=100.5, P=48, R-16, GI sounds decreased ventrally
Rectal: nephrosplenic space is identified, pelvic flexors is enlarged and firmer, fecal contents are soft, fecal and most tight, SI not identified.

What is your diagnosis

Answer 25

Pelvic flexure impaction

Question 26

What is your treatment plan for pelvic flexure impaction

Answer 26

Analgesics- banamine
Mineral oil, water, electrolytes via NG tube

Question 27

8yr old Mustang gelding presents with acute colic and fever. Prior to this end healthy with great appetite for alfalfa hay. What is most likely etiology of this horses illness

Answer 27

Cantharidin

Question 28

Mini horse with 1 week history of lameness. Owner calls and reports has not improved even after given 1 gram tablet of phenylutazone twice per day just like when her thoroughbred was lame, but mini seems cockily. Which anatomical structure are you concerned about

Answer 28

Right dorsal colon