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| + | * Has potentially lethal effects in the monogastric animal. |
| + | |
| + | |
| + | ===Water Loss=== |
| + | |
| + | * Fluid loss is evident as: |
| + | *# An increased PCV or haematocrit. |
| + | *# An increased total protein concentration. |
| + | *# A prerenal azotaemia. |
| + | |
| + | |
| + | ===Gastric Electrolyte Loss=== |
| + | |
| + | * The main losses are of H<sup>+</sup> and Cl<sup>-</sup>, and also K<sup>+</sup> |
| + | * Can potentially cause metabolic alkalosis, although this is only likely with disease which stops at the pylorus, e.g.: pyloric outflow obstruction. |
| + | ** In cases where mild alkalosis occurs, homeostatic mechanisms produce a more alkaline urine to restore normal body pH. |
| + | ** However, in severe metablolic alkalosis with marked dehydration, acidic urine may be produced- this is termed '''paradoxical aciduria'''. |
| + | *** Because [[Control of Feeding - Anatomy & Physiology#The Vomit Reflex|vomiting]] induceses hypokalaemia, there is an overriding stimulus in the kidney for Na<sup>+</sup> (and therefore water) retention. |
| + | *** Na+ can only be resorbed in exchange for H+ |
| + | **** H<sup>+</sup> is therefore excreted in the urine, causing it to be acidic. |
| + | *** [[Control of Feeding - Anatomy & Physiology#The Vomit Reflex|Vomiting]] also induces hypochloraemia, meaning bicarbonate rather than chloride is resorbed with the Na+ to maintain electrical neutrality |
| + | **** This perpetuates the alkalosis. |
| + | * [[Control of Feeding - Anatomy & Physiology#The Vomit Reflex|Vomiting]] does not occur in the ruminant although [[The Abomasum - Anatomy & Physiology|abomasal]] content may reflux into the [[Stomach and Abomasum - Anatomy & Physiology|forestomachs]]. |
| + | ** Sequestration of secretions in the [[The Abomasum - Anatomy & Physiology|abomasum]] will have similar effects to pyloric outflow obstruction with [[Control of Feeding - Anatomy & Physiology#The Vomit Reflex|vomiting]] in the monogastric animal. |
| + | *** e.g. abomasal torsion |
| + | *** Causes dehydration, hypochloraemia, hypokalaemia and metabolic alkalosis. |
| + | |
| + | |
| + | * Lesions in the [[Small Intestine - Anatomy & Physiology|small intestine]] can also lead to [[Control of Feeding - Anatomy & Physiology#The Vomit Reflex|vomiting]] |
| + | ** Both gastric acid and pancreatic and intestinal bicarbonate secretions are lost |
| + | *** Animal consequently has a normal pH or may even be acidotic. |
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| + | |
| ==The Vomit Reflex== | | ==The Vomit Reflex== |
| [[Image:The Vomit Reflex Pathway.jpg|right|thumb|150px|The Vomit Reflex - Copyright nabrown RVC]] | | [[Image:The Vomit Reflex Pathway.jpg|right|thumb|150px|The Vomit Reflex - Copyright nabrown RVC]] |