Abomasal Disorders

Question 1

What is the most common displacement of the abomasum

Answer 1

LEFT DISPLACED ABOMSAUM (lda)

Question 2

What breed is predisposed to LDA

Answer 2

Dairy cattle, especially deep chested Holsteins

Question 3

How is age a factor in LDA

Answer 3

Less common in primiparous/heifers
Older cattle higher risk

Question 4

How is stage of lactation a factor in LDA

Answer 4

80% of LDAs within 4 weeks postpartum

Question 5

What are other risk factors besides age in LDA

Answer 5

Infectious disease
mastitis, metritis, enteritis, lameness
Metabolic disease
hypocalcaemia, negative energy balance

Question 6

How is Transition cow nutrition a factor in LDA

Answer 6

Reduced dry matter intake pre-calving
High concentrate intake pre-calving

Question 7

LDA diagnosis- History

Answer 7

Reduced feed intake
Drop in milk production
Decline in rumination time (if monitored)
Recent calving
Concurrent postpartum disease

Question 8

LDA diagnosis- Clinical Exam

Answer 8

Characteristic “ping” on auscultation and ballottement
Dull

Question 9

What is pH level of fluid from abdominocentesis

Answer 9

<3.5

Question 10

Three catergories to correct LDA

Answer 10

Conservative management
Percutaneous fixation
Surgical fixation

Question 11

What does conservative manage of LDA entail

Answer 11

Cast & roll
Little evidence to support the use of medical management alone High recurrence rate

Question 12

What does Percutaneous fixation of LDA entail

Answer 12

Cast into dorsal recumbency
Clip and surgical scrub from sternum to umbilicus
Instill 10-20ml local anesthetic at surgical sites
With cow in dorsal recumbency identify “ping”
Insert trocar at caudal site, push toggle through then clamp suture end to hold
Move ~10cm up to cranial site and repeat process
Tie both suture together loosely
Leave one hand’s width between suture and body wall
Risk of necrosis if too tight
Roll cow clockwise into sternal recumbency

Question 13

Advantages of Percutaenous fixation

Answer 13

Quick and easy
Minimal specialist equipment needed
Inexpensive

Question 14

Disadvantages of percutaenous fixation

Answer 14

Safety risk with casting and rolling
Require 2+ assistants
Risk of ventral fistula formation
Blind technique so risk of incorrect fixation

Question 15

What does surgical correction of LDA entail

Answer 15

right flank incision
Locate then deflate abomasum
Reposition abomasum

Question 16

Differentiate advantages between right and left flank approach to correct LDA

Answer 16

Right
Standing animal
Do not require assistants
Good access for abdominal exploration
Ensures correct fixation of the omentum or abomasum

Left
Best technique in pregnant animals (space to work)
Standing animal
Good access to the abomasum so can treat adhesions or ulcers
Ensures direct fixation of the abomasum

Question 17

Differentiate disadvantages between right and left flank approach to correct LDA

Answer 17

Right-
Technically more difficult
More invasive surgery with risk of wound infection or peritonitis
Risk of recurrence if pexy fails
Wrong position
Omentum too friable
Risk of pyloric stenosis (pyloropexy)

Left
Requires assistant
Risk of damage to the milk vein
Risk of ventral fistula formation

Question 18

What approach is contraindicated in pregnant cow

Answer 18

Paramedian approach

Question 19

Does Right displaced abomasum and volvulus or LDA have more clinical signs

Answer 19

RAV more severe clinical signs
Signs of colic
Elevated heart rate and respiratory rate
Signs of shock and endotoxaemia
Palpable distended viscus behind last rib

Question 20

What surgical approach to use for RDA

Answer 20

Only right flank approach appropriate (not left flank or paramedian)

Question 21

Dietary causes of impaction

Answer 21

Fibrous diet low in protein and energy
Heavy ingestion of sand
Poor water availability

Question 22

Non-dietary causes of impaction

Answer 22

Abomasal hypomotility in postpartum dairy cattle
Any cause of reduced abomasal outflow e.g Vagal nerve damage

Question 23

Most common reason for loss of wall intergrity

Answer 23

Abomasal ulceration

Question 24

Outline the 4 types of ulceration

Answer 24

Type 1- Non-perforating ulcer without bleeding
No or minimal clinical signs

Type 2- Non-perforating ulcer bleeding into the abomasal lumen
Melena and signs of anaemia

Type 3- Melena and signs of anaemia
No melena, often minimal signs if walled off

Type 4- Perforating ulcer with generalised peritonitis
No melena, non-specific sick cow depending on severity

Question 25

Abomasal ulceration diagnosis

Answer 25

C/S
Faecal occult blood test
Haematology and biochemistry
Low PCV and total protein (Type II)
Inflammatory response (Type III or IV)
Ultrasound of the ventral abdomen +/- abdominocentesis
Exploratory laparotomy

Question 26

Abomasal ulcer treatment

Answer 26

Offer high fibre diet
Supportive therapy
Blood transfusion (Type II)
Oral antacids (magnesium oxide, aluminium hydroxide)
Cimetidine, ranitidine, omeprazole are not licensed in food producing animals in UK
Surgery (Type III or IV)

Question 27

What is an abomasal fistula

Answer 27

Infrequently develop following abomasopexy
Intraluminal suture placement can allow leakage of abomasal content and weakening of the incision