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Also known as:  '''''Twisted stomach — LDA — RDA
 
Also known as:  '''''Twisted stomach — LDA — RDA
    
==Introduction==
 
==Introduction==
This is much less dramatic than a [[Gastric Dilatation and Volvulus|displaced stomach in the dog]], and develops chronically.  
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Generally, this is much less dramatic than a [[Gastric Dilatation and Volvulus|displaced stomach in the dog]], and develops chronically, although abomasal volvulus is a comparable condition.
The [[Abomasum - Anatomy & Physiology|abomasum]] is the fourth stomach of the cow and hangs loosely by the omentum. It can move from its normal position to left displacement where it becomes trapped under the rumen or a right displacement which may result in abomasal volvulus and torsion.  
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The [[Abomasum - Anatomy & Physiology|abomasum]] is the fourth chamber of the cow stomach and hangs loosely by the omentum. It can move from its normal position to left displacement where it becomes trapped under the rumen or a right displacement which may result in abomasal volvulus and torsion.  
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Rearrangement of abdominal viscera in pregnancy is thought to be an important aetiological factor, however reduced abomasal motility is thought to be the primary aetiological cause. Once the abomasum is displaced gas production by the organ continues causing distension and further displacement.  
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Rearrangement of abdominal viscera in pregnancy is thought to be an important aetiological factor, however reduced abomasal motility is thought to be the primary aetiological cause. Once the abomasum is displaced gas production by the organ continues causing distension and further displacement.
    
==Signalment==
 
==Signalment==
A disease of the cow affecting mainly high yielding [[Bovine Breeds - WikiNormals#Dairy Breeds|dairy cows]] on high concentrate diets. Usually occurs in the first 6 weeks of [[Lactation - Species Differences Cow - Anatomy & Physiology|lactation]]. Sometimes displacement does occur before calving, this is in late gestation and accounts for 5% of cases.  
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A disease of the cow affecting mainly high yielding [[Bovine Breeds - WikiNormals#Dairy Breeds|dairy cows]] on high concentrate diets. Left displacements usually occur in the first 6 weeks of [[Lactation - Anatomy & Physiology|lactation]], although this association is less strong for right-sided displacements and cases of abomasal volvulus. Sometimes displacement does occur before calving, this is in late gestation and accounts for 5% of cases.
    
==Diagnosis==
 
==Diagnosis==
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==History and Clinical Signs==
 
==History and Clinical Signs==
A typical history would be a recently calved cow with a sudden drop in appetite and milk production. Animals display general malaise and abdominal pain. On clinical exam a rapid loss of condition may be evident, [[Ketosis of Cattle|ketosis]] or decreased ruminal activity on ausculatation. Often the left flank bulges behind ribs and the temperature may be normal or slightly raised.
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A typical history would be a recently calved cow with a sudden drop in appetite and milk production. Animals display general malaise and abdominal pain. On clinical exam a rapid loss of condition may be evident, [[Ketosis of Cattle|ketosis]] or decreased ruminal activity on ausculatation. Often the left ribs appear 'sprung', with a concave left paralumbar fossa, and the temperature may be normal or raised.
    
==Pathogenesis==
 
==Pathogenesis==
 
There are two manifestations of abomasal displacemet. In both the abomasum becomes trapped between [[Rumen - Anatomy & Physiology|rumen]] and abdominal wall. The more common presentation is the '''left displacement (LDA''') which is ventral and to the left of the rumen. The [[Omasum - Anatomy & Physiology|omasum]], [[Reticulum - Anatomy & Physiology|reticulum]] and [[Liver - Anatomy & Physiology|liver]] are also displaced.
 
There are two manifestations of abomasal displacemet. In both the abomasum becomes trapped between [[Rumen - Anatomy & Physiology|rumen]] and abdominal wall. The more common presentation is the '''left displacement (LDA''') which is ventral and to the left of the rumen. The [[Omasum - Anatomy & Physiology|omasum]], [[Reticulum - Anatomy & Physiology|reticulum]] and [[Liver - Anatomy & Physiology|liver]] are also displaced.
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Abomasal atony and increased gas production leads to displacement. Factors reducing abomasal motility include a high concentrate diet, increased [[Volatile Fatty Acids|volatile fatty acids]] from the rumen and periparturient disease e.g ketosis, hypocalcaemia and metritis. Displacement to the left results in a reduced flow of ingesta as well as reduced digestion resulting in anorexia and [[Dehydration - Pathology|dehydration]].  
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Abomasal atony and increased gas production leads to displacement. Factors reducing abomasal motility include a high concentrate diet, increased [[Volatile Fatty Acids|volatile fatty acids]] from the rumen, increased Non-Esterified Fatty Acids from body fat mobilisation, hypokalaemia<ref>Turck, G. & Leonhard-Marek (2010) Potassium and insulin affect the contractility of abomasal smooth muscle. Journal of Dairy Science. 93, 3561-3568</ref>, hyperinsulinaemia <ref>Turck, G. & Leonhard-Marek (2010) Potassium and insulin affect the contractility of abomasal smooth muscle. Journal of Dairy Science. 93, 3561-3568</ref><ref>Pravettoni, D., Doll, K., Hummel, M., Cavallone, E., Re, M. & Belloli, A.G. (2004) Insulin resistance and abomasal motility disorders in cows detected by use of abomasoduodenal electromyography after surgical correction of left displaced abomasum. American Journal of Veterinary Research, 65, 1319-1324</ref> and periparturient disease e.g ketosis, hypocalcaemia and metritis. There are also genetic differences in mediators of abomasal motility <ref>Sickinger, M.M., Leiser, R.R., Failing, K.K., Doll, K.K. (2008) Evaluation of differences between breeds for substance P, vasoactive intestinal polypeptide, and neurofilament 200 in the abomasal wall of cattle. American Journal of Veterinary Research. 69, 1247-1253</ref>Displacement to the left results in a reduced flow of ingesta as well as reduced digestion resulting in anorexia and [[Dehydration|dehydration]].  
    
A '''displacement to the right (RDA)''' is less common. Decreased abomasal motility, distension and displacement occurs as in the LDA.  
 
A '''displacement to the right (RDA)''' is less common. Decreased abomasal motility, distension and displacement occurs as in the LDA.  
 
Rotation of the abomasum on its mesenteric axis leads to volvulus and constriction of blood vessels and trauma to the vagus nerve resulting in abomasal distenstion with blood-stained fluid and gas, congested mucosa and necrosis of the abomasum, dehydration and circulatory collapse.  
 
Rotation of the abomasum on its mesenteric axis leads to volvulus and constriction of blood vessels and trauma to the vagus nerve resulting in abomasal distenstion with blood-stained fluid and gas, congested mucosa and necrosis of the abomasum, dehydration and circulatory collapse.  
Additionally the abomasum may rupture, causing peritonitis, shock and death.  
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Additionally the abomasum may rupture, causing peritonitis, shock and death.
    
==Laboratory Tests==
 
==Laboratory Tests==
Often a severe ketosis is present resulting in raised blood butyrate.
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Often a severe ketosis is present resulting in raised blood beta-hydroxybutyrate.
    
If electrolyte levels  and blood gas are measured affected animals develop a hypochloraemia and metabolic alkalosis due to reduced outflow of ingesta from the abomasum combined with continued secretion of hydrochloric acid into the abomasum.  
 
If electrolyte levels  and blood gas are measured affected animals develop a hypochloraemia and metabolic alkalosis due to reduced outflow of ingesta from the abomasum combined with continued secretion of hydrochloric acid into the abomasum.  
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Hypokalaemia also develops due to the alkalosis which drives potassium into cells combined with a reduced intake due to anorexia.
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Hypokalaemia also develops due to alkalosis (or hyperinsulinaemia in certain cases), which drives potassium into cells combined with a reduced intake due to anorexia.
    
==Treatment==
 
==Treatment==
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Toggles are useful in low value animals as it is a cheap and fast technique.  The animal is cast and rolled onto her back. Two toggles are inserted through the ventral abdominal wall into the abomasal lumen. Once positioned the two toggles are tied together. Following this blind suture it is possible to toggle the incorrect area (e.g. rumen, reticulum) resulting in fatal complications. To avoid this complication a pH strip can be used to confirm the correct location following cannulation before the toggles are put in place.  
 
Toggles are useful in low value animals as it is a cheap and fast technique.  The animal is cast and rolled onto her back. Two toggles are inserted through the ventral abdominal wall into the abomasal lumen. Once positioned the two toggles are tied together. Following this blind suture it is possible to toggle the incorrect area (e.g. rumen, reticulum) resulting in fatal complications. To avoid this complication a pH strip can be used to confirm the correct location following cannulation before the toggles are put in place.  
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*'''Right flank omentopexy'''
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*'''Right flank (pyloro-)omentopexy'''
The right flank is incised one hands distance behind the last rib and the displaced abomasum is located. The organ is then deflated and repositioned in the correct location. The abomasum is sutured to the abdominal wall and the incision is closed in a routine manor.
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The right flank is incised one hands distance behind the last rib and the displaced abomasum is located. The organ is then deflated and repositioned in the correct location. The omentum (+/- pylorus) is sutured to the abdominal wall and the incision is closed in a routine manor.
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*'''Left flank abomasopexy/"Utrecht"'''
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The left flank is incised just caudal to the last rib and the omentum adjacent to the abomasum is located. A continuous, partial thickness nylon or absorbable suture line with long tails is placed in the body of the abomasum then both ends are passed through separate points on the ventral body wall. An assistant can help locate the correct position for the suture to be passed by palpating the region with a pair of artery forceps. The two pieces of suture are tied externally and hold the abomasum in the correct position whilst adhesions form.
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*'''Right paramedian abomasopexy'''
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For this technique the cow is sedated and cast onto her back. An incision is made to the right of midline caudal to the most posterior part of the sternum. The abomasum is located, repositioned and sutured to the body wall.
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*'''Left flank omentopexy'''
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*'''Laparoscopic techniques'''
The left flank is incised just caudal to the last rib and the omentum adjacent to the abomasum is located. A long nylon suture is passed through the fat a few times and then both ends through separate points on the ventral body wall. An assistant can help locate the correct position for the suture to be passed by palpating the region with a pair of artery forceps. The two pieces of suture are tied externally and hold the abomasum in the correct position whilst adhesions form.
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Three general laparoscopic techniques have been developed, the two-step (Janowitz) <ref>Janovitz, H. (1998) Laparoskopische Reposition und Fixation des nach links verlagerten Labmagens beim Rind. Tierarztl Prax, 26 (G), 308-313</ref>, the one-step (Christiansen/Barisani) procedures<ref>Christiansen K. Laparoskopisch kontrollierte Operation des nach links verlagerten Labmagens (Janowitz-Operation) ohne Ablegen des Patienten. Tierärz Prax, 2004; 32(5):118-121.</ref><ref>Barisani C. Evoluzione della tecnica di Janowitz per la risoluzione della dislocazione abomasale sinistra secondo Barisani. Summa, 2004; 5:35-39.</ref>, and the recumbent one-step method (Newman) <ref>Newman KD, Anderson DE, Silveira F. One-step laparoscopic abomasopexy for correction of left-sided displacement of the abomasum in dairy cows. JAVMA, 2005; 227(7):1142-1147, 1090</ref>. Both the Janowitz and Christiansen/Barisani methods start with port placement in the left paralumbar fossa of the standing cow, followed by abomasal trocharisation under laparoscopic guidance, modified toggle placement and deflation of the displaced abomasum. Then, in the two-step Janowitz procedure, the cow is rolled, two more portals are placed ventrally, and the suture line of the preplaced toggle is retrieved and tied externally around a piece of gauze. In the standing one-step method, a special tool (spieker) is introduced through the left 11-12 intercostal space or through the paralumbar fossa and is used to push the toggle (and abomasum) ventrally and pierce the body wall in the desired location, where it is again tied externally. In the recumbent one-step method (Newman), the cow is anaesthetised in dorsal recumbency and an intracorporeal suture line is placed under laparoscopic guidance to anchor the abomasal body to the ventral abdominal wall, reducing the risk of abomasal fistula formation by avoiding perforation of the abomasal lumen.  
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*Right paramedian abomasopexy
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Advantages of laparoscopic methods may include a more rapid procedure, faster recovery to milk and gastrointestinal motility and lower postoperative morbidity/mortality (compared with right flank omentopexy) <ref>Wittek, T., Locher, L.F., Alkaassem, A., Constable, P.D. (2009) Effect of surgical correction of left displaced abomasum by means of omentopexy via right flank laparotomy or two-step laparoscopy-guided abomasopexy on postoperative abomasal emptying rate in lactating dairy cows. Journal of the American Veterinary Medical Association. 5, 652-657.</ref>, and validation of toggle placement, lower morbidity/mortality, visualisation of concurrent pathology, and potentially a lower redisplacement rate (vs blind toggle placement). The prime disadvantages are the cost of the equipment required, and a steep learning curve for intracorporeal suturing (Newman method). Laparoscopic techniques for correction of right-sided displacements and cases of abomasal volvulus have also been developed <ref>Kümper H, Seeger T (2003) Labmagenverlagerung beim erwachsenen Rind. Teil 3: Therapie (Fortsetzung), prae- und postoperative Behandlung, Prognose. Tierärztliche Praxis, 31 (G), 224-230</ref>.
For this technique the cow is sedated and cast onto her back. An incision is made to the right of midline caudal to the most posterior part of the sternum. The abomasum is located, repositioned and sutured to the body wall.  
   
   
 
   
 
It is important for all surgical techniques that post-operatively the cow is given a large amount of roughage and concentrates are introduced into the diet slowly.
 
It is important for all surgical techniques that post-operatively the cow is given a large amount of roughage and concentrates are introduced into the diet slowly.
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==Prognosis==
 
==Prognosis==
Following surgical correction of an uncomplicated displacement success rates can reach 95%. Abomasomal volvulus and the presence of an abomasal ulcer are associated with a much poorer prognosis. Additionally tachycardia, decreased temperature, black faeces and a long period of illness are all associated with poorer outcomes.
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Following surgical correction of an uncomplicated displacement, short term success rates can reach 95%. Abomasomal volvulus and the presence of an abomasal ulcer are associated with a much poorer prognosis. Additionally tachycardia, decreased temperature, black faeces and a long period of illness are all associated with poorer outcomes.
 
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==Literature Search==
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[[File:CABI logo.jpg|left|90px]]
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Use these links to find recent scientific publications via CAB Abstracts (log in required unless accessing from a subscribing organisation).
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<br><br><br>
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[http://www.cabdirect.org/search.html?q=(title:(displac*)+AND+title:(abomas*)+AND+title:(left))+OR+(title:(LDA)+AND+od:(cattle)) Left Displaced Abomasum publications]
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[http://www.cabdirect.org/search.html?start=0&q=(title:(displac*)+AND+title:(abomas*)+AND+title:(right))+OR+(title:(RDA)+AND+od:(cattle)) Right Displaced Abomasum publications]
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Longer term survival after correction of Left Displaced Abomasums is poorer, with 79% and 73% of animals surviving beyond 2 months for a blind toggle and a paramedian abomasopexy respectively in one study, although the difference between procedures was not significant<ref>Sterner, K.E., Grymer, J., Bartlett, P.C. & Miekstyn, M. (2008) Factors influencing the survival of dairy cows after correction of left displaced abomasum. Journal of the American Veterinary Medical Association. 232, 1521-1529</ref>.  The most likely reasons for the slightly poorer long-term survival after LDAs are mastitis, lameness, poor production and infertility.
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[http://www.cabi.org/cabdirect/FullTextPDF/2010/20103063335.pdf ''' Management of abomasal displacement.''' Wilson, D. G.; Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada, Large Animal Veterinary Rounds, 2008, 8, 8, pp 1-6, 20 ref. - '''Full Text Article''']
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{{Learning
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|literature search = [http://www.cabdirect.org/search.html?q=(title:(displac*)+AND+title:(abomas*)+AND+title:(left))+OR+(title:(LDA)+AND+od:(cattle)) Left Displaced Abomasum publications]<br>[http://www.cabdirect.org/search.html?start=0&q=(title:(displac*)+AND+title:(abomas*)+AND+title:(right))+OR+(title:(RDA)+AND+od:(cattle)) Right Displaced Abomasum publications]
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|full text = [http://www.cabi.org/cabdirect/FullTextPDF/2010/20103063335.pdf ''' Management of abomasal displacement.''' Wilson, D. G.; Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada, Large Animal Veterinary Rounds, 2008, 8, 8, pp 1-6, 20 ref.]<br>[http://www.cabi.org/cabdirect/FullTextPDF/2006/20063094825.pdf ''' Right paramedian abomasopexy as a surgical treatment for left abomasal displacement in dairy cows: a review of 115 cases.''' Podpecan, O.; Zemljič, B.; Veterinarska Fakulteta, Univerza v Ljubljani, Ljubljana, Slovenia, Slovenian Veterinary Research, 2006, 43, Supplement 10, pp 201-204, 19 ref.]
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}}
    
==References==
 
==References==
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Andrews, A.H, Blowey, R.W, Boyd, H and Eddy, R.G. (2004) Bovine Medicine (Second edition), Blackwell Publishing  
 
Andrews, A.H, Blowey, R.W, Boyd, H and Eddy, R.G. (2004) Bovine Medicine (Second edition), Blackwell Publishing  
[[Category:Stomach_and_Abomasum_-_Pathology]][[Category:Cattle]]
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<references/>
[[Category:Expert_Review]]
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{{review}}
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[[Category:Stomach_and_Abomasum_-_Pathology]][[Category:Gastric Diseases - Cattle]]
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[[Category:Brian Aldridge reviewing]]
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