Bloat and Traumatic Reticulitis PDF

Bloat and Traumatic Reticulitis Emma Fishbourne and Dai Grove-White Learning objectives    Describe the main surgical conditions of the gastrointestinal tract. Describe the aetiology of these conditions and their association with nutrition Describe surgical treatment of these conditions Re...

Bloat and Traumatic Reticulitis Emma Fishbourne and Dai Grove-White Learning objectives    Describe the main surgical conditions of the gastrointestinal tract. Describe the aetiology of these conditions and their association with nutrition Describe surgical treatment of these conditions Revision - The Rumen  200 + litres capacity  Fermentation chamber  Lots of gas produced – lost by eructation  Bloat occurs when loss of gas is prevented Ruminal Tympany (Bloat)    “accumulation of rumen gas sufficient to change contour of rumen” Visible distension 2 types   free gas bloat – less common – obstruction or animal unable to burp! frothy bloat – more common, stable foam produced on top of the rumen liquid which blocks the release of the gas Clinical Signs      Rumen on the LHS – therefore distended left abdomen. As distension continues whole abdomen can become distended. Often painful – reluctant to move and eat, appear distressed, vocalisation Respiratory distress Death can occur quickly – especially once an animal is recumbant Can affect either 1 or 2 individuals or lots (more affected with frothy bloat) http://www.vivo.colostate.edu/hbooks /pathphys/digestion/herbivores/tympa ny.html Free Gas Bloat  Loss of gas prevented i.e.  Obstruction of the oesophagus     Foreign Body e.g. potatoes 2° to chronic pneumonia – mediastinal abcesses 2° to other conditions which interfere with rumenoreticular motility (wire, vagal indigestion, milk fever, tetanus) Posture – animal gets ‘cast’ Frothy bloat    More common, stable foam produced on top of the rumen liquid which blocks the release of the gas Occurs most commonly in animals on pasture containing alfalfa, lucerne or clover – rapidly digested in the rumen and form fine particles that trap gas bubbles Or can see in animals fed high levels of finely ground grain Diagnosis   History – especially feeding history! Clinical Signs! Treatment – Free Gas   Pass stomach tube Trochar  in emergency   Chronic bloat    taut rumen “red devil” rumen fistula Treat underlying condition Treatment – Frothy Bloat Pass stomach tube  Trochar Won’t Work Alone – need to dose with surfactant then exercise:     oils e.g. vegetable oil (200-500mls) Silicone based commercial preparation e.g. simethicone If emergency – 4-6” incision – L sublumbar fossa Prevention      Avoid high risk pastures at high risk times i.e. soon after turn out, when wet Buffer feed Restrict access – strip graze Administer antifoaming agents – spray grass Remove animals with recurrent bloat Traumatic Reticulitis History: 1. 2. 3. 4. 5. Sudden MILK DROP e.g. - 20l to 5l. Hunched up appearance. Stiff gait. Inappetent. Often fed a TMR. Where does the reticulum lie?  Opposite 6 – 8 th rib on LHS. Rumen Contractions: 3 rumen / reticular contractions in 2 mins. 2 types of contractions Primary and secondary cycles. 1°: 2° 2:1. (varies)  Summary of Rumen Contractions Primary Cycle FIRST RETICULAR Primary CycleCONTRACTION Coarse material to dorsal sac FIRST RETICULAR CONTRACTION SECOND RETICULAR CONTRACTION Coarse material to dorsal sac Fine material to cranio-dorsal blind sac SECOND RETICULAR CONTRACTION Fine material to omasum Fine material to cranio-dorsal blind sac DORSAL RUMEN CONTRACTION Fine material to omasum Fine material from CONTRACTION cranio-dorsal blind sac DORSAL RUMEN to reticulum Fine material from cranio-dorsal blind sac Coarse material circled back to caudoto reticulum dorsal blind sac and up Coarse material circled back to caudoSome exchange with ventral sac dorsal blind sac and up VENTRAL RUMEN CONTRACTION Some exchange with ventral sac Fine material circulated back to cranial VENTRAL RUMEN CONTRACTION blind sac and up Fine circulated back Somematerial exchange with dorsal sacto cranial blind sac and up Some fine material into cranio-dorsal blind Some sac exchange with dorsal sac Some fine material into cranio-dorsal Secondary Cycle blind sac DORSAL RUMEN CONTRACTION Secondary Cycle Gas cap pushed forward and gas released DORSAL RUMEN CONTRACTION up oesophagus Gas cap pushed forward and gas released up oesophagus Ratio 2 Primary : 1 secondary Regurgitation Regurgitation Start again Primary cycle: Secondary cycle:  biphasic.  rumen contraction  mixing cycle.  starts in caudal  contraction of reticulum rumen  pushes gas to  then contraction of cardia rumen.  ERUCTATION Diagnosis  Eric Williams Test      Withers Pinch – abdominal pain Pole Test – abdominal pain (localise) Faeces – stiffer with long fibre   Listen over trachea Feel rumen contractions in L flank Individual cow not group (SARA) WBC count – non-specific In practical terms: Eric-Williams test. 1° cycle:  Place right hand in left sub lumbar fossa.  Stethoscope over trachea  Feel contraction.  No eructation. 2° cycle. Feel the contraction. Observe the eructation. with traumatic reticulitis: There is pain on reticular contraction:  3 scenarios: 1. Reduction in 1° cycles 2. Grunt immediately prior to 1° . 3. Breath holding prior to 1° . 4. Very subtle Causes: 1. 2. 3. 4. 5. From tyres – fall into feeder wagons Perished tyres. Baling sheep netting. Nails fall into mixer wagons. Etc Old fencing wire – outside etc Not fussy eaters. Clinical signs:     sudden onset – drop in yield increased temp 39.50 reduced rumen contractions. Eric Williams test.      hunched up   Reduced number of 10 contractions +ve early on -ve later on lesion walled off Adducted elbows inappetant , dull, depressed. Further tests:  withers pinch.   pole test.    localise lesion metal detector. neutrophillia & left shift.   +ve for any pain More neutrophills than lymphocytes exploratory rumenotomy. Consequences of swallowing a wire   If no penetration – no effect Penetration – local reticulo-peritonitis   Ventral/lateral – better prognosis Medial       Damage to vagus Abcess in medial wall No pain receptors Pericardium – pericarditis Other organs – lungs, spleen etc Generalised peritonitis Heart Traumatic pericarditis.    pulse and temp – raised very ill – “toxic” heart sounds    initially – pericardial rub later – very quiet /absent later “washing machine sounds” Hear failure develops ……..     Distended jugular V. Visible jugular pulse Sub-mandibular oedema Hopeless prognosis Exploratory rumenotomy. 1. 2. Left sub lumbar fossa. Incise. Not too high or low. 3. Palpate abdomen. Retic 4. 5. 6. 7. 8. 9. Exteriorise cranial portion of rumen. 2 bone pins act as anchors. Sterile towels as a seal around rumen. Incise rumen. Hand forward. Locate reticulum. 10.   11. Search for FB- often ventral. Does she feel pain as you manipulate. More than 1 wire. Close rumen: Cushing or Lembert. After care: 1. 2. 3. 4. 5. Antibiotics. NSAIDS. Return to milk yield. Magnets for others. Stop using tyres. Vagus indigestion. Etiology  Complication of traumatic reticuloperitonitis.  Vagus nerve injury.   Penetration in medial wall of reticulum Reticular adhesions. Etiology  Vagus nerve injury and dysfunction:  dorsal vagus nerve injury.    pyloric branch of ventral vagal nerve.   • achalasia of reticulo omasal orifice. = enlarged rumen ± bloat achalasia of pylorus = abomasal impaction. hypermotility OR hypomotility of rumen – Depends on fibre types damaged  often no gross lesion:   microscopic lesions in medial wall damage of vagal tension receptors. reticular adhesions.   most important cause. extensive inflammation   inhibits reticular motility disturbs the particle separation process. Other causes: 1. 2. 3. actinobacillosis of rumen / reticulum. fibropapillomas of cardia. late pregnancy. History  traumatic reticulitis.   several weeks to months earlier. often undiagnosed Pathogenesis  disturbance in rumen outflow disturbance in pylorus outflow    rumenal distension pasty / frothy contents alteration in reticulo rumen motility.    hypermotile OR hypomotile ratio of 10: 20 contractions upset “chaotic” Clinical findings. • • • • • chronic: inappetence / loss of BCS. “10 to 4” appearance. hypo/hyper motile “vague” “chaotic”          dehydration. enlarged rumen. scant faeces. undigested material inadequate response to tx. distended abomasum in lower right quadrant. hypermotile (4-6 / min) Or hypomotile with rumen atony & bloat ping on right lower flank – sometimes ! Differential diagnosis: 4. chronic traumatic reticulitis. abomasal impaction / dietary in origin. omasal impaction. abomasal ulceration. 5. “vague & chaotic” 1. 2. 3. Treatment  1. 2. 3. prognosis is poor - slaughter rumen lavage. fluid therapy and laxatives. rumenotomy / Red Devil. Other reasons for rumenotomy: 1. 2. Unable to relieve bloat via stomach tube. Reccurring chronic bloat. Now over to Rob…..  Unless you have any other questions…..