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[[Image:Diagram of ruminating contractions.jpg|thumb|right|150px|Diagram of ruminating contractions - Copyright RVC 2008]]
 
[[Image:Diagram of ruminating contractions.jpg|thumb|right|150px|Diagram of ruminating contractions - Copyright RVC 2008]]
*Reflex initiated by mechanical stimlation of the receptors in the mucosa of the [[The Reticulum - Anatomy & Physiology|reticulum]], ruminoreticular fold and cardiac area of the [[The Rumen - Anatomy & Physiology|rumen]]
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*Reflex initiated by mechanical stimulation of the receptors in the mucosa of the [[The Reticulum - Anatomy & Physiology|reticulum]], ruminoreticular fold and cardiac area of the [[The Rumen - Anatomy & Physiology|rumen]]
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*Frequency of contractions depends on the animal's activity
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*Frequency of contractions depends on the animal's feeding activity and diet contents
 
*E.g. Cattle fed on hay or straw have the most frequent contractions at 79-100 per hour during feeding, 55-76 per hour during rumination
 
*E.g. Cattle fed on hay or straw have the most frequent contractions at 79-100 per hour during feeding, 55-76 per hour during rumination
*E.g. Cattle that are resting (not feeding or ruminating) only have contractions 47-80 per hour
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*E.g. Cattle that are resting (not feeding or ruminating) only have contractions at 47-80 per hour
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*Discrete reticular contraction preceedes biphasic ruminal contraction (see [[The Rumen - Anatomy & Physiology#Ruminoreticular contraction|ruminoreticular contractions]])
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*Discrete reticular contraction preceeds biphasic ruminal contraction (see [[The Rumen - Anatomy & Physiology#Ruminoreticular contraction|ruminoreticular contractions]])
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*Rumination depends upon the coordination of the stomach movements with the thoracic wall and throat
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*Regurgitation depends upon the coordination of the stomach movements with the thoracic wall and throat: inspiration against a closed glottis creating a negative pressure in the thorax - allowing ingesta to be drawn into the [[Oesophagus - Anatomy & Physiology|oesophagus]]
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*Associated with inspiration against a closed glottis creating a negative pressure in the thorax allowing ingesta to be drawn into the [[Oesophagus - Anatomy & Physiology|oesophagus]]
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*Ingesta carried to the oral cavity via an antiperistaltic wave
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*Ingesta carried orally via an antiperistaltic wave
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*the process is controlled by rumination centres in the hypothalamus
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*Controlled by rumination centres in the hypothalamus
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*Fibre increases stomach motility (type and length of fibre is important)
 
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*Fibre increases stomach motility
      
*Increase in [[Volatile Fatty Acids - Anatomy & Physioogy|volatile fatty acids]] decrease stomach motility
 
*Increase in [[Volatile Fatty Acids - Anatomy & Physioogy|volatile fatty acids]] decrease stomach motility
      
==Function==
 
==Function==
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