Changes

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.

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. Displacement to the left results in a reduced flow of ingesta as well as reduced digestion resulting in anorexia and [[Dehydration|dehydration]].  

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.  

*'''Laparoscopic techniques'''

*'''Laparoscopic techniques'''

Two general laparoscopic techniques have been developed, the two-step (Janowitz) and the one-step (Christianssen/Barisani) procedures. Both 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 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 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. Advantages include a more rapid procedure, faster recovery to milk and gastrointestinal motility and lower postoperative morbidity/mortality (compared with right flank omentopexy), and validation of toggle placement, lower morbidity/mortality, visualisation of concurrent pathology, and a lower redisplacement rate (vs blind toggle placement). The prime disadvantage is the cost of the equipment required. Laparoscopic techniques for correction of right-sided displacements and cases of abomasal volvulus have also been developed.

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.

 

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>.

   

   

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.

==Prognosis==

==Prognosis==

Following surgical correction of an uncomplicated displacement short-term success rates can reach 95%. Longer-term success rates are marginally poorer, with one study demonstrating survival beyond 2 months of 79% for blind toggle and 73% for paramedian abomasopexy, although the difference in success rates 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>. 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.

Following surgical correction of an uncomplicated displacement, short term success rates can reach 95%. Longer term survival 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>. 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.

==Literature Search==

==Literature Search==

<references/>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<references>

<references/>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<references>

<references/>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. <references>

 

 

 

 

 

 

 

<references/>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<references>

{{review}}

{{review}}

[[Category:Stomach_and_Abomasum_-_Pathology]][[Category:Gastric Diseases - Cattle]]

[[Category:Stomach_and_Abomasum_-_Pathology]][[Category:Gastric Diseases - Cattle]]

[[Category:Brian Aldridge reviewing]]

[[Category:Brian Aldridge reviewing]]