21. Abomasal impaction and reflux syndrome

Question 1

Abomasal impaction Ethiology

Answer 1

Abomasal impaction (obturation)

Etiology

• Sand or rough hard fodder + lack of drinking water
• Occurs in feedlot bulls and sheep,

Question 2

Clinical signs of Abomasal Impaction?

Answer 2

Clinical signs

• similar to abomasal ulcer
• but other characteristic local signs abomasum: firm, sand sack-like palpatory finding

Question 3

Treatment and surgery?

Answer 3

Treatment

• Conservative

o Spasmolytics, laxatives + fluid and electrolyte replacement

• Surgery

o Rumenotomy or abomasotomy

Question 4

Reflux Syndrome ( intraruminal vomitus- Hoflund syndrome, posterior functional stenosis ?

Answer 4

Consequence in the rumen: H+ and Cl- increase o PhysiologicabomasalpH2-4

• 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 Normalvalue<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

Pathogenesis?

Answer 5

Question 6

Clinical signs?

Answer 6

Clinical signs

• Accumulation of abomasal fluid within the rumen

o Local

§ Dilatation of rumen= undulating, thin (watery)/ sour- smelling content

o General

§ Dehydration

• Exsiccosis: eyes, CRT incr, PCV incr, GFR decr
• Extrarenal uremia: urine-like breath, creatinine incr

§ Metabolic alkalosis

• Respiration rate decr, swallow breathing

o + characteristic clinical signs of the underlying abomasal disease

o !!! reflux could be a negative cause of any abomasal diasease and is usually not the primary problem