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==Introduction==

| Also known as:

[[Image:traumatic reticulitis.jpg|right|thumb|200px|<small><center>'''Traumatic pericarditis'''. Courtesy of A. Jefferies</center></small>]]

| '''Hardware Disease <br> Traumatic Reticuloperitonitis<br> Wires'''

 

Due to their unselective feeding habits, cattle may ingest a variety of foreign bodies. Cattle cannot spit out metallic agents (e.g. screws, nails, pieces of wire, bottle tops) once in their mouths, and so ingest them. Heavier metallic objects consumed can become lodged in the [[Reticulum - Anatomy & Physiology|reticulum]], and may penetrate the reticular wall under the influence of the continuous [[Reticulum - Anatomy & Physiology#Ruminoreticular contraction|reticular movements]] or forces caused by pregnancy and parturition.

Due to their unselective feeding habits, cattle may ingest a variety of foreign bodies. Cattle cannot spit out metallic agents (e.g. screws, nails, pieces of wire, bottle tops) once in their mouths, and so ingest them. Heavier metallic objects consumed can become lodged in the [[Reticulum - Anatomy & Physiology|reticulum]], and may penetrate the reticular wall under the influence of the continuous [[Reticulum - Anatomy & Physiology#Ruminoreticular contraction|reticular movements]] or forces caused by pregnancy and parturition.

Pathological changes depend on the direction of penetration; this is usually in an anterior-ventral direction. Pyogenic bacteria escape from the [[Reticulum - Anatomy & Physiology|reticulum]], causing localised [[Peritonitis|peritonitis]] and local fibrinous adhesions.

Pathological changes depend on the direction of penetration; this is usually in an anterior-ventral direction. Pyogenic bacteria escape from the reticulum, causing localised [[Peritonitis|peritonitis]] and local fibrinous adhesions.

Penetration of the [[Diaphragm - Anatomy & Physiology|diaphragm]] and pericardium results in [[Pericarditis|pericarditis]]. Penetration of the [[Heart - Anatomy & Physiology|heart]] itself results in [[Myocarditis|myocarditis]] and [[Endocarditis|endocarditis]]. Penetration of the [[Lungs - Anatomy & Physiology|lungs]] and pleura can occur resulting in pneumonia and pleurisy.

Penetration of the [[Diaphragm - Anatomy & Physiology|diaphragm]] and [[Heart Structure - Anatomy & Physiology#Pericardium|pericardium]] results in [[Traumatic Pericarditis|pericarditis]]. Penetration of the [[Heart - Anatomy & Physiology|heart]] itself results in [[Myocarditis|myocarditis]] and [[Endocarditis|endocarditis]]. Penetration of the [[Lungs - Anatomy & Physiology|lungs]] and pleura can occur resulting in pneumonia and pleurisy.

[[Liver - Anatomy & Physiology|Liver]] and [[Spleen - Anatomy & Physiology|splenic]] abscesses also occasionally occur following penetration of either organ.

Liver and splenic abscesses also occasionally occur following penetration of either organ.

==Signalment==

==Signalment==

More frequently affects adult dairy cows but does also affect beef animals. More comon in cows grazing a pasture where there has been previous building.

More frequently affects adult dairy cows but does also affect beef animals. More common in cows grazing a pasture where there has been a previous building.

==Diagnosis==

==Diagnosis==

Signs are often vague, but adult cattle will show a drop in milk production and fecal output is decreased. The rectal temperature is often mildly increased. The heart rate is often increased, and respiration is usually shallow and rapid. Initially, the cow exhibits abdominal pain with an arched back; and a reluctance to move often with abducted elbows.

Signs are often vague, but adult cattle will show a drop in milk production and fecal output is decreased. The rectal temperature is often mildly increased. The heart rate is often increased, and respiration is usually shallow and rapid. Initially, the cow exhibits abdominal pain with an arched back; and a reluctance to move often with abducted elbows.

Affected animals will also grunt in response to the 'bar test'.

Affected animals will also grunt in response to the 'bar test' - Two people, one on each side of the cow, hold a bar/pole underneath the animal in the region behind its front legs. They attempt to 'lift' the cow and the cow grunts in response to the pressure on its chest.

==Laboratory Tests==

==Laboratory Tests==

==Pathology==

==Pathology==

 

Thick walled, pus filled abscesses form around the points of penetration, which may be multiple.

Thick walled, pus filled abscesses form around the points of penetration, which may be multiple.

The foreign object may be found in one of these abscesses, or free in the reticular lumen.

The foreign object may be found in one of these abscesses, or free in the reticular lumen.

If the[[Structure of the Heart - Anatomy & Physiology#Pericardium| pericardium]] is penetrated it becomes thickened with oedema, and purulent fluid containing fibrin clots accumulates in the sac giving  a “bread and butter heart” which is classical of traumatic reticulitis.

If the pericardium is penetrated it becomes thickened with oedema, and purulent fluid containing fibrin clots accumulates in the sac giving  a “bread and butter heart” which is classical of traumatic reticulitis.

Additionally if the liver is affected large abscesses in the dorsal part of the liver may erode into the posterior vena cava to produce a [[Thrombosis|thrombosis]].

Additionally if the liver is affected large abscesses in the dorsal part of the [[Liver - Anatomy & Physiology|liver]] may erode into the posterior vena cava to produce a [[Thrombosis|thrombosis]].

==Treatment==

==Treatment==

==Prevention==

==Prevention==

Animals should not graze fields where they may have access to metal objects or where construction has recently taken place. Pastures should be cleared as much as possible of metal wire and such like prior to animals grazing. Additionally magnets can be administered to the cattle orally, these then remain in the reticulum and if metal objects are ingested they will remain attatched to the magnet.

Animals should not graze fields where they may have access to metal objects or where construction has recently taken place. Pastures should be cleared as much as possible of metal wire and such like prior to animals grazing. Additionally magnets can be administered to the cattle orally, these then remain in the reticulum and if metal objects are ingested they will remain attached to the magnet.

 

 

 

==References==

==References==

Merck & Co (2008) '''The Merck Veterinary Manual''' (Eighth Edition) ''Merial''  

Merck & Co (2008) '''The Merck Veterinary Manual''' (Eighth Edition) ''Merial''  

[[Category:Forestomach - Inflammatory Pathology]][[Category:Cattle]][[Category:To_Do_-_Caz]]

 

[[Category:To_Do_-_Review]]

 

[[Category:Forestomach - Inflammatory Pathology]][[Category:Gastric Diseases - Cattle]]

[[Category:Brian Aldridge reviewing]]