Changes

==Description==

==Description==

This is much less dramatic than a displaced [[Monogastric Stomach - Anatomy & Physiology|stomach]] in the dog, and develops chronically.  

This is much less dramatic than a displaced [[Monogastric Stomach - Anatomy & Physiology|stomach]] in the dog, and develops chronically.  

The [[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 displcement where it becomes trapped under the rumen or a right displacement which may result in abomasal [[Volvulus, Intestinal|volvulus]] and [[Torsion, Intestinal|torsion]].  

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 displcement where it becomes trapped under the rumen or a right displacement which may result in abomasal [[Volvulus, Intestinal|volvulus]] and [[Torsion, Intestinal|torsion]].  

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.  

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.  

===Pathogenesis===

===Pathogenesis===

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

Abomasal atony and increased gas production leads to displacement. Factors reducing abomasal motility include a high concentrate diet, increased [[Volatile Fatty Acids - Anatomy & Physioogy|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]].  

A displacement to the right an RDA is less common. Decreased abomasal motility, distension and displacement occurs as in the LDA.  

A displacement to the right an 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 [[The Abomasum - Anatomy & Physiology|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 [[Abomasum - Anatomy & Physiology|abomasal]] distenstion with blood-stained fluid and gas, congested mucosa and necrosis of the abomasum, dehydration and circulatory collapse.  

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

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

==Laboratory Tests==

==Laboratory Tests==