Abomasal Disease

Question 1

Discuss abomasal related conditions?

Answer 1

Several related conditions

• Left displaced abomasum (LDA)
• Right displaced abomasum (RDA)
• Abomasal torsion/volvulus(AV)
• Abomasal ulceration

Relatively common in dairy cows

Common features in pathophysiology

Question 2

Discuss the occurence of the related conditions in abomasal disease?

Answer 2

Left displaced abomasum very common

• Range of incidence rates quoted from 0.25 –5% in UK
• Probably near 5% in USA (more difficult to manage in more high yielding herds)
• Around 1.5% in Germany

Right displaced abomasum

• Similar signs to LDA
• Less common

Abomasal torsion

• Abdominal emergency
• Severe colic signs
• Even less common

Abomasal ulceration

• May be no/mild signs or can be severe/fatal
• Incidence uncertain!

Question 3

What can lead to a drop in abomasal motility?

Answer 3

Question 4

What can lead to RDA and LDAs?

Answer 4

Question 5

What happens after abomasal dilation?

Answer 5

Question 6

How do LDA, RDAs and AVs occur?

Answer 6

Pathophysiology

• Similar mechanisms behind all three presentations (LDA, RDA, AV)
• Which one occurs may depend on stage of lactation (LDA most often close to calving)
• There is also an element of chance!

Question 7

What are the risk factors abomasal disease?

Answer 7

Things that decrease DMI around calving

• Cows over-fat at calving
  
  • Often also have fat infiltration of liver
• Poor calving management
• Periparturient disease/problems e.g. hypocalcaemia, mastitis, metritis, dystocia
• Poor feed access/palatability

Lack of dietary long fibre

• (poss related to rumen fill)

Poor control of energy balance around calving

• (often have subclinical ketosis before LDA)

Sudden concentrate feeding at calving/no concentrate fed in transition

Hypocalcaemia

• Decreased GI motility

Often peak incidence in spring

• ? Related to lack of fibre in spring grass or sudden change in diet at turnout

Question 8

LDA clinical signs?

Answer 8

Clinical signs

• Decreased yield (classically 5-10 ltrs)
• Decreased feed intake (especially concentrate)
• Poor rumen turnover
• May be signs of underlying primary disease (e.g. metritis, mastitis)
• May show mild colic (rare)

Question 9

LDA diagnosis?

Answer 9

Diagnosis –percussion auscultation “ping”

Question 10

LDA diagnosis extra?

Answer 10

Diagnosis

• May also hear spontaneous abomasal noises on left (“tinkling”)
  
  • May elicit spashing/tinkling/ping on ballottment
  • Very commonly ketotic
    
    • Positive Rotheras/urine ketonetest
  • ALWAYS look for underlying primary disease!!!
• May come and go
  
  • “swinging LDA”

Question 11

LDA Abomasum treatment options?

Answer 11

• Coservative
• Semi-surgical
• Surgical

Question 12

Discuss LDA conservative treatment?

Answer 12

Conservative treatment

• Roll the cow (+/-sedation)
• Cast onto right hand side
  
  • Reuff’s method (ref AHW1)
• Slowly roll through dorsal recumbency onto left side
• +/-…
  
  • Brief “stop” in dorsal recumbency
  • Shaking the cow from side to side while in dorsal
• Other reason to roll a cow is for uterine torsion

Question 14

Depict LDA rolling?

Answer 14

Question 15

Discuss conservative treatment to be used alongside rolling?

Answer 15

The following may be used in conjunction with rolling…

• Oral propylene glycol
• Oral fluids/electrolytes (stomach tube)
• Oral probiotics
• Systemic prokinetics(metoclopramide (promote abomasum contractility), erythromycin???, iv calcium?)
  
  • Licensing –can’t use metoclopramide
• Long-fibre only diet for 24hrs (e.g. good quality hay)

Conservative treatment

• ~75-80% reported to relapse

Question 16

Discuss semi-surgical treatment for LDA?

Answer 16

Semi-surgical treatment

• toggle
• Roll as for conservative treatment (+/-sedation)
• Insert “toggles” through trochar into abomasum while cow in dorsal recumbency

Question 18

Surgical treatment options for LDA?

Answer 18

• Paramedian
• Bilateral flank
• Left flank
• Right flank

Question 19

Discuss the surgical paramedian approach to LDA treatment?

Answer 19

Paramedian approach

• As toggle but open abdomen to visualise abomasum
• Requires more sedation, local anaesthesia
• Remember licensing!
• Suture abomasal fundus to ventral body wall –partial thickness
• Often include abomasum in closure of muscle layer

Question 20

Discuss the surgical bilateral flank approach to LDA treatment?

Answer 20

Surgical – bilateral flank approach

• Two surgeons, standing cow
• Local anaesthesia (e.g. paravert) & skin prep
• Paralumbar fossa incision on each side

Left surgeon…

• Identifies and decompresses abomasum (ballottment, can use sterile 16g needle and tubing)
• Passes under abdominal contents via ventral midline to…

Right surgeon

• Brings abomasum to right side
• Fixes abomasum in place

Question 21

Surgical - bilateral flank approach options for fixation?

Answer 21

Omentopexy:

• Continuous suture in omentum, each end sutured to muscle layer

Pyloropexy:

• Suture through partial thickness pylorus and through muscle

Question 22

What can be seen here?

Answer 22

Pyloric region of abomasum

Question 23

Discuss surgical right flank surgery to treat LDA?

Answer 23

Surgical – right flank approach

• One-surgeon version of bilateral flank
• Paralumbar fossa incision on right side
• Abomasum palpated on left side by reaching round behind rumen

Question 24

Discuss right flank approach further?

Answer 24

• +/-abomasum deflated using needle/tubing
• Falls/guided into ventral midline
• Located by surgeon and gently pulled up to incision
• Pylorus/omentum indentified and pexied

Question 25

Describe left flank approach to LDA surgery?

Answer 25

Surgical – left flank approach * Standing, left paralumbar fossa incision * Abomasum identified and continuous suture line placed in fundus with very long ends left on suture material * Abomasum decompressed if necessary * Needle attached to one end of suture material and passed ventrally through abdomen (guarded!) and poked out through ventral body wall to assistant * Repeated with second needle, two ends of material secured on outside as abo repositioned

Question 27

Discuss surgical laproscopy treatment for LDA?

Answer 27

* Various techniques described * Becoming more popular in Europe and UK * Some methods involve rolling * Others are done standing

Question 28

Discuss LDA prevention?

Answer 28

**Prevention** **Key points** * Maximise DMI around calving/early lactation * Transition diet: some but not too much concentrate, sufficient long fibre * Fresh calved diet: sufficient long fibre * Early lactation energy balance * Check milk fever control (e.g. high incidence clinical cases?) * Check incidences of other diseases (e.g. metritis) and association with LDA cases

Question 29

Look at this flow diagram of LDA?

Answer 29

Question 30

Describe the pathophysiology of RDA?

Answer 30

Question 31

Clinical signs of RDA and diagnosis?

Answer 31

**Clinical signs** * Similar to LDA but usually more severe * May also show mild colic **Diagnosis** * Auscultation during percussion and ballottment * Similar sounds to LDA, different location!...

Question 32

Where does a RDA go?

Answer 32

Question 33

RDA conservative treatment?

Answer 33

**Treatment-conservative** * Often first line if no signs of a torsion **Medical** * Gastric motility modifiers (metoclopramide (NO), hyoscine/dipyrone (Buscopan), erythromycin?) * Usually repeated x2-3 q12hrs * NSAIDs? Meloxicam * Iv calcium also sometimes used in hope will stimulate abomasal contractility **Dietary management** * Long fibre only diet (hay) * Comes down to feeding lots of hay and giving meloxicam Buscopan commonly used (unlikely to be gastric prokinetic, response ? related to analgesia) –little evidence to justify. Also not permitted for use in lactating cows –VMD have suggested they wouldn’t support this as use under the cascade

Question 34

RDA Surgical treatment?

Answer 34

Treatment – surgical * If significant colic, ­ HR or conservative Tx fails * Standing right flank approach * Abomasum decompressed * Best by exeriorising/emptying * Can use needle/tubing or large bore tube/purse string suture * Checked for signs of ulceration (oversewn if severe) * Pyloropexy normally performed to prevent torsion **Prognosis not as good as LDA**

Question 35

Discuss abomasal torison (AV)?

Answer 35

* Normally a sequel of RDA, but may not present until torsion occurs * Require emergency surgery

Question 36

Clinical signs of abomasal torsion (AV)?

Answer 36

Similar signs to RDA but… * Usually some colic signs, may be severe * HR normally higher (typically \>80-100/min) * Usually sparse/no faeces in rectum * May be signs of circulatory compromise * Low temperature, discoloured mucous membranes, clinically evident dehydration, poor pulse quality

Question 37

Discuss abomasal torsion surgical treatment?

Answer 37

Treatment – surgical * Standing right flank laporotomy * Empty abomasum as much as possible (tube) * Identify and correct torsion * Often several axes of torsion (can be very difficult!) * Perform pyloropexy and close SuppportiveTx… * Fluids, NSAIDs etc * Guarded/poor prognosis (consider euthanasia)

Question 38

Discuss abomasal uclers?

Answer 38

Abomasal ulceration * May be secondary to LDA/RDA * Also appears to occur by itself * Possibly related to… * Stress/concurrent disease * Ingestion of soil/sand?

Question 39

Discuss abomasal ulceration?

Answer 39

* Probably significantly under-diagnosed * Common incidental finding at slaughter/PME * Signs often mild, may self-cure * Even if penetrated, omentummay seal off (picture courtesy of BCVA photo library) * Can also cause severe signs (colic, poor production) * May even be fatal

Question 40

Abomasal ulceration clinical signs and management?

Answer 40

**Clinical signs** * Mild colic, may be inapparent * Pain on ballottement right ventral abdomen * Melaena/faecal occult blood * Signs of peritonitis **Management** * Euthanasia often advocated once melaena established Analgeisa? (care –NSAIDs may be ulcerogenic) Antacids? * Antibiotics

Question 41

Conclusions on abomasal injury?

Answer 41

**Conclusions** * The abomasal disease complex consists of a variety of related conditions * LDA is very common in dairy cattle and has major welfare/economic consequences * There are a variety of treatment options * As always, prevention is better than cure!