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Bloat (view source)

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==Description==

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Bloat is the ruminal distension caused by the accumulation of gas produced by the fermentation process.

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Bloat is the ruminal distension caused by the accumulation of gas produced by the fermentation process. Bloat can be categorised according to cause into Primary bloat (frothy bloat) and secondary bloat (free gas bloat).

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===Primary bloat===

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Occurs following ingestion of large amounts of succulent green plant material. This is highly fermentable and produces large amounts of gas.

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*** Material contains high levels of soluble proteins. These act as foaming agents by reducing surface tension but increasing surface viscosity of rumenal liquids and a stable rumenal foam forms.

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*** The [[Volatile Fatty Acids - Anatomy & Physioogy|volatile fatty acids]] of the plant material consumed lower pH, optimising conditions for formation of froth.

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*** Gas present in bubble form is insufficient to trigger eructation, and so the [[The Rumen - Anatomy & Physiology|rumen]] becomes distended.

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===Seconday bloat===

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** '''Free gas bloat/ Secondary bloat'''

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*** May be:

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**** '''Acute'''

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*****Due to sudden [[Oesophagus - Anatomy & Physiology|oesophageal]] obstruction, for example by a solid foreign body (e.g. a piece of potato or turnip).

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**** '''Chronic'''

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***** Results from partial [[Oesophagus - Anatomy & Physiology|oesophageal]] obstruction/ compression, or from interference with the normal eructation mechanism, e.g. with:

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****** partially obstructive foreign bodies

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****** actinobacillosis in the oesophagus or [[Oesophageal groove|oesophageal groove]]

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****** [[Oesophagus - Anatomy & Physiology|oesophagus]] or groove tumours

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****** chronic inflammatory or adhesive disease of the [[The Reticulum - Anatomy & Physiology|reticulum]]

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***** Some passage of gas is possible, so gas build-up and distenesion is more prolonged.

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***** Interference with cardiac and respiratory function is seldom life threatening.

==Signalment==

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==References==

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*The disease is acute and progressive and will result in death in a matter of hours.

===Pathology===

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** [[Oesophagus - Anatomy & Physiology|Oesophageal]] "bloat line" at thoracic inlet.

*** Congested and haemorrhagic cranially, pale caudally.

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~~===Pathogenesis===~~

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* There are two forms of bloat:

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** '''Frothy bloat/ Primary bloat'''

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*** Occurs following ingestion of large amounts of succulent green plant material. This is highly fermentable and produces large amounts of gas.

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