Abdominal distension Flashcards
All clinical exams should include assessment of rumen, shape, filland motility.
What informatin does this provide you with?
How is rumen contour and motility assessed?
Provides key information on feed intake and potential causes of distension
- Decreased motility = Sensitive for disease, Not specific for which disease
Rumen contour (shape)
- Early in exam
- From a distance
- Rear and side of cow
- Gaunt, normal or distended
Rumen motility
- Simultaneous auscultation and palpation
- Count contractions (3 in 2 mins)
- Primary and secondar contractions not differentiated
when/why does hypermotility occur?
Why does hypomotility occur?
Hypermotility:
- Relatively uncommon finding on clinical exam
- Early rumen distension –> as stretch receptors stimulated
- Increase in primary contractions as result
- Physiologically normal response to a large meal
- Contractions cease if distension continues
Hypomotility:
- Systemic inflammation
- Increased sympathetic tone
- Rumen distension or acidosis
what are the differentials for abdominal bloat?
- Bloat - frothy or free gass
- Acidosis
- Oesophageal obstruction
- Pregnancy
- Vagal indigestion
- Urethral obstruction +/-ruptured urethra
- GI obstruction, impaction or displacement
- Traumatic reticulitis/TRP
- Peritonitis
- Ascites - Liver, cardiac or renal failure; hypoproteinaemia
- Miscellaneous - Clostridial disease, neoplasia, overeating etc
what ancillary diagnostic tests can be done for abdominal distension?
what should the pH of the rumen be?
how can you test the activity of the protozoa of the rumen?
- Rumen fluid analysis
- Colour, pH, protazoal activity, methylene blue reduction time, chloride concentration (will be high if there is an obstruction)
- Blood chemistry profiles
- Metabolic state?
- Ultrasonography
- Rumenotomy (opening the rumen)
pH 5 - 5.5
protozoa activity - methylene blue reduction time - colourless in 2 mins
what is Bloat?
what are the types?
- Ruminal dilation or abdominal distension?
(Rumen most commonly responsible)
Primary = frothy bloat
Secondary = gassy bloat
Ruminal tympany = same thing!
what is frothy bloat?
what is the aeitology?
what are the clinical signs?
how do you differentiate it?
- Formation of stable froth in rumen as a result of diet
- Usually associated with lush pasture, clover and legumes
- Fatal
- Severe distension –> Compression of thoracic viscera
- Cattle > sheep - Same presentation in sheep
Clinical signs:
* Abdominal enlargement of left-hand side when viewed from rear
* Colic
* Kicking, treading, lying down and rising, vocalisation
* Stretched stance, rear feet placed far behind
* Decreased rumen motility
Beware heavily fleeced sheep…will hide apperance
Differential diagnosis - Stomach tube passes but doesn’t decompress
what are the two pathophysiology of frothy bloat?
Legumes:
- High threshold stretch receptors inhibit motility
- Less saliva –> increase in rumen liquor viscosity
- Fluid higher in chloroplast membrane fragments and soluble proteins –> prevents reflex relaxation of cardia –> eructation not possible
Low fibre and high concentrate diets:
- Less saliva –> increase in rumen liquor viscosity
- Microbial polysaccharide production
- Polysaccharides + increased liquor viscosity = stable foam
what is the treatment for frothy bloat?
what is the emergency treatment that farmers can do?
- Anti-foaming agents (e.g. Mineral oil, poloxalene – “BloatGuard”)
- Rumenotomy decompression
- Severe cases (prognosis?)
- Diet management:
- Pasture: take off pasture, late morning grazing, strip graze, feed hay before going onto grass
- Add long fibre to diet
Emergency treatment:
- large needle or scalple - stab incision behind the last rib at the highest point of the side
What is free gas bloat?
what is the aetiology?
what is the treatment?
Secondary: inability to eliminate gas by eructation secondary to another condition
- Obstruction: foreign body (may be palpable)
- Hypocalcaemia
- Prolonged lateral recumbency
- Vagal nerve damage
- Tetanus (rigidity, protrusion 3rd eyelid, hyperesthesia)
- Actinobacillus
- Outside pressure (carcinoma, papilloma, EBL, bTB)
Identify and treat the primary cause
what does Vagal nerve damage/injury cause?
what are the clinical signs?
‘Vagal indigestion’:
* enlarged rumen>bloat
* Secondary to hardware disease/TRP, actinobacillosis (rumen/reticulum), peritonitis, abscessation
* characterized by dysfunction of reticulorumen
* hinders the passage of ingesta from the reticulorumen, abomasum or both, resulting in the distension of the abdomen
Clinical signs: non-specific
* Decreased milk yield, anorexia
* Abnormal faeces
* Recurrent bloating
* Decreased ruminal motility
there are two forms of vagal indigestion, describe them
Anterioir function stenosis:
* Insufficient excitatory stimuli from vagus nerve
* Decreased motor drive of the primary reticular cycle
* Paralysis of omasum and reticuloomasal orifice
* Substantial reticular adhesions prevent normal ingesta and fluid flow to reticuloomasal orifice
* Decreased/absent flow into omasum so rumen distends
Pyloric outflow failure:
* Issue with vagus nerve near the abomasum
* Accumulation of ingesta in abomasum and omasum
* Abomasal content enters the rumen
* Severe distension and decrease in forestomach motility
* Increased fluid retention in rumen
* Marked dehydration and hypochloremic metabolic alkalosis (as Cl- trapped in the rumen, kidney will try and fix, reabsorbes bicarbonate )
What are causes of choke (obstruction) on cattle and sheep?
what is the general treatment?
Common in sheep and cattle!
Large quantities of feed, rapid intakes
Root crops
Potatoes, turnips, apples, fodder beet etc
Placenta (sheep!)
Profuse salivation and bloat
Distressed, extended neck, coughing
Obstruction sites:
Oropharynx, thoracic inlet, heart base
Palpable/pass stomach tube
Diagnosis = history and clinical signs
Treatment:
- Attempt removal using fingers or gentle pressure with stomach tube (using paraffin/cooking oil or lubricant)
- Leave to macerate if rumen trocar/red devil is present
- If severe relieve rumen tympany - Trocar and cannula in left paralumbar fossa
what therapeutics are used for choke in cattle and sheep?
Spasmolytic IV/IM
Hyoscine Butylbromide + Metamizole
Spasmium comp.
Licensing:
- Has license for dairy cows
- Use in pregnancy after benefit-risk assessment by vet
- As supportive therapy for acute diarrhoea
But Do not use in cases of:
- gastro-intestinal ulceration
- chronic gastro-intestinal disorders
- mechanic stenoses in the gastro-intestinal system
Sedation IM/IV - Xylazine
Licensing:
- Pre-medication for minor superficial operations, painful manipulative procedures and local or regional anaesthesia.
But :
- Increased risk of regurgitation
- Increased risk of recumbency
- Not for use in latter stages of pregnancy except at parturition
when does ruminal bloat occur?
what are the clinical signs?
what is the management?
- Usually slightly older calves
- Poor oesophageal groove closure
- Often just after weaning
- Causes not well understood
- Related to poor rumen development
Clinical signs
* Much more chronic
* Diarrhoea, poor hair coat, decreased DLWG
* Often recurrent bloat
* May follow concentrate feeding
Management
* Short term deflate with stomach tube
* Long term fistula or trocar
what is the cause of abomasal bloat?
what is the signalment?
what is seen on clinical exam?
what is the treatment?
what is the managment?
Cause:
- Rapid gas production in abomasum
- Excessive fermentation of simple carbs
- Overgrowth of gas producing bacteria
Signalment
- Pre-weaned calves, 1-3 weeks old, Usually dairy
Clinical exam
* Splashing on abdominal percussion
* Right ventral abdominal distension
* Colic
Treatment
* Relieve bloat (tube or needle)
* IVFT
* Antibiotics (penicillin) (think there is a bacterial cause, betalactam or penicillin)
* Hyoscine
* NSAIDs
Management
* Review milk feeding (concentration, hygeine)
* Secondary abomasal ulceration?
