Abomasal Disorders Flashcards
What is the most common displacement of the abomasum
LEFT DISPLACED ABOMSAUM (lda)
What breed is predisposed to LDA
Dairy cattle, especially deep chested Holsteins
How is age a factor in LDA
Less common in primiparous/heifers
Older cattle higher risk
How is stage of lactation a factor in LDA
80% of LDAs within 4 weeks postpartum
What are other risk factors besides age in LDA
Infectious disease
mastitis, metritis, enteritis, lameness
Metabolic disease
hypocalcaemia, negative energy balance
How is Transition cow nutrition a factor in LDA
Reduced dry matter intake pre-calving
High concentrate intake pre-calving
LDA diagnosis- History
Reduced feed intake
Drop in milk production
Decline in rumination time (if monitored)
Recent calving
Concurrent postpartum disease
LDA diagnosis- Clinical Exam
Characteristic “ping” on auscultation and ballottement
Dull
What is pH level of fluid from abdominocentesis
<3.5
Three catergories to correct LDA
Conservative management
Percutaneous fixation
Surgical fixation
What does conservative manage of LDA entail
Cast & roll
Little evidence to support the use of medical management alone High recurrence rate
What does Percutaneous fixation of LDA entail
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
Advantages of Percutaenous fixation
Quick and easy
Minimal specialist equipment needed
Inexpensive
Disadvantages of percutaenous fixation
Safety risk with casting and rolling
Require 2+ assistants
Risk of ventral fistula formation
Blind technique so risk of incorrect fixation
What does surgical correction of LDA entail
right flank incision
Locate then deflate abomasum
Reposition abomasum
Differentiate advantages between right and left flank approach to correct LDA
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
Differentiate disadvantages between right and left flank approach to correct LDA
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
What approach is contraindicated in pregnant cow
Paramedian approach
Does Right displaced abomasum and volvulus or LDA have more clinical signs
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
What surgical approach to use for RDA
Only right flank approach appropriate (not left flank or paramedian)
Dietary causes of impaction
Fibrous diet low in protein and energy
Heavy ingestion of sand
Poor water availability
Non-dietary causes of impaction
Abomasal hypomotility in postpartum dairy cattle
Any cause of reduced abomasal outflow e.g Vagal nerve damage
Most common reason for loss of wall intergrity
Abomasal ulceration
Outline the 4 types of ulceration
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
Abomasal ulceration diagnosis
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
Abomasal ulcer treatment
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)
What is an abomasal fistula
Infrequently develop following abomasopexy
Intraluminal suture placement can allow leakage of abomasal content and weakening of the incision
