17. Pathogenesis of the abomasal displacement, general and local consequences of abomasal displacement

Question 1

Pathogenesis of the abomasal displacement?

Answer 1

Nutritional abnormalities (intake: higher grain/ lower fibre; due to the increased milk production post calving) -

increased VFA in abomasum-hypomotility/atony of abomasum- dilatation of abomasum- displacement

Question 2

For RDA with torsion?

Answer 2

General consequences of abomasal displacement
• For RDA with torsion

Ischemia (necrosis)

Tissue perfusion

Lactate

Metabolic acidosis

Question 3

Local consequences of abomasal displacement?

Answer 3

Local consequences of abomasal displacement

• For both LDA and RDA
• Abomasal motility decreases

o Abomasal passage disturbed and/or stopped abomasal digestion decr

o Reflux syndrome

• Abomasal ulceration= peritonitis

Question 4

Consequence in the Rumen of abomasal displacement?

Answer 4

Consequence in the rumen: H+ and Cl- increase

o Physiologic abomasal pH 2-4

• HCl rarely causes severe acidosis (HCl- acidosis), due to the buffering effect of saliva, ammonia, and proteins
• Cl- is not absorbable from the rumen; its concentration can be determined in the rumen fluid

photometrically

o Normal value <30mmol/L

• Physiologically: Cl- from the abomasum goes into the small intestine and is absorbed there into the blood

stream, HCO3- is absorbed from the blood to the intestines

Question 5

Clinical signs of reflux syndrome?

Answer 5

Clinical signs of reflux syndrome

• Accumulation of abomasal fluid within the rumen
• Local:

o Dilatation of rumen → undulating, thin (watery)/sour- smelling content

• General:

o Dehydration → exsiccosis: eyes, CRT↑, PCV↑, GFR↓,