Changes

==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. On clinical exam A rapid loss of condition may be evident, ketosis, decreased ruminal activity on ausculatation. Often the left flank bulges behind ribs and the temperature may be normal or slightly raised.

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]], decreased ruminal activity on ausculatation. Often the left flank bulges behind ribs and the temperature may be normal or slightly raised.

 

===Pathogenesis===

===Pathogenesis===

* There are two manifestations of [[The Abomasum - Anatomy & Physiology|abomasal]] displacemet. In both the [[The Abomasum - Anatomy & Physiology|abomasum]] becomes trapped between [[The Rumen - Anatomy & Physiology|rumen]] and abdominal wall.  

* There are two manifestations of [[The Abomasum - Anatomy & Physiology|abomasal]] displacemet. In both the [[The Abomasum - Anatomy & Physiology|abomasum]] becomes trapped between [[The Rumen - Anatomy & Physiology|rumen]] and abdominal wall.  

*# '''Ventral and to the left of [[The Rumen - Anatomy & Physiology|rumen]] (LDA)''' - the more common presentation.

*# '''Ventral and to the left of [[The Rumen - Anatomy & Physiology|rumen]] (LDA)''' - the more common presentation.

 

*#* [[The Abomasum - Anatomy & Physiology|Abomasal]] atony and increased gas production lead to displacement

*#* [[The Abomasum - Anatomy & Physiology|Abomasal]] atony and increased gas production lead to displacement. The condition is induced by the combination of a high concentrate diet, hypocalcaemia and increased [[Volatile Fatty Acids - Anatomy & Physioogy|volatile fatty acids]] from the [[The Rumen - Anatomy & Physiology|rumen]]. A displacement to the right an RDA is less common.

*#** Is induced by the combination of a high concentrate diet, hypocalcaemia and increased [[Volatile Fatty Acids - Anatomy & Physioogy|volatile fatty acids]] from the [[The Rumen - Anatomy & Physiology|rumen]].

*# '''To the right of rumen (RDA)''' - less common.

*#* Constriction of blood vessels and trauma to the vagus nerve results in [[The Abomasum - Anatomy & Physiology|abomasal]] distenstion with blood-stained fluid and gas, congested mucosa and infarction.

*#* Constriction of blood vessels and trauma to the vagus nerve results in [[The Abomasum - Anatomy & Physiology|abomasal]] distenstion with blood-stained fluid and gas, congested mucosa and infarction.

*#* The [[The Abomasum - Anatomy & Physiology|abomasum]] may rupture, causing peritonitis, shock and death.  

Additionally the [[The Abomasum - Anatomy & Physiology|abomasum]] may rupture, causing peritonitis, shock and death.  

*May be associated with secondary development of ketosis.

*May be associated with secondary development of ketosis.