Topic 61 - Motility of the forestomachs, eructation, rumination Flashcards
1
Q
Words to include in motility of the forestomach
A
- Light bolus
- Heavy bolus
- Gas pocket
- Reticular-rumen cycle
- Reticular contraction
- Resting
- Ruminating
- Erucating
- Fermentation product
- Density
- Biphasic contraction
- Reguritation
- Mixing
- Omasal contraction
2
Q
Words to include in rumination
A
- Saliva
- Physiological pH
- Reflex mechanism
- Mechanoreceptors
- Ruminal mucosa
- Afferent fibers
- N. vagus
- Reflux
- Myencephalon
- Ventral area of hypothalamus
- Efferent fibers
- Salivary glands
- Esophagus
- Reticulum
- Reguritation
- Remastication
- Redegutition
3
Q
Words to include in erucation
A
- Gas production
- CO2
- Methane
- Stretch receptors
- Antiperistaltic gas transport
- Esophagus
- Pharynx
- Nasopharyngeal closure
- Alveolar air
4
Q
Words to include in motility of the omasum
A
- Water
- Electrolytes
- Suckling effect
- Suckling-pressure pump
- Reticulo-omasal opening
5
Q
Words to include in motility of abomasum
A
- Peristaltic wave
- Recurrent flow
6
Q
Words to include in innervation
A
- Parasympathetic
- N. vagus
- Sympathetic
- Plexus solearis
7
Q
Topics to include in the essay
A
- General about light bolus and heavy bolus
- Motility of the forestomach
- Ruminoreticular cycle
- Erucation
- Rumination
- Ruminoreticular cycle
- Motility of omasum
- The role of the reticulo-omasal opening
- Motility of abomasum
- Innervation of the forestomach
8
Q
How does the light bolus travel?
A
- Kept in dorsal sac of rumen for a longer period of time, until it becomes dense enough to sink down to the ventral sac
- Reticulum
- Omasum
- Abomasum
9
Q
How does the heavy bolus travel?
A
- Enters directly to the ventral sac, then the reticulum shortly
- Omasum
- Abomasum
- Microbial action happens in the rumen, so the light bolus food gets more exposed to it than the heavy
10
Q
Motility of the forestomach
General
A
- In ruminants, cyclic and spontaneous contraction occurs in the first three compartments of the stomach
- The motility of the compartments is divided into:
- Reticular-rumen cycle
- Omasal contraction
- Rumen contracts 6-8 times in 5 minutes
11
Q
Motility of the forestomach
Ruminoreticular cycle
A
- Types of activity:
- Resting
- Rumination
- Erucation
- Role: separating the fermentation products according to their density, and mixing the forestomach content and transporting it to the abomasum
- The contraction starts in reticulum and spreads through rest of the rumen in a highly specific manner
-
Reticulum
- Biphasic contraction
-
Cranial sac
- Contraction inhibits flow between the cranial and caudal sacs
-
Caudodorsal sac
- Contraction pushes content to the ventral direction
- Mixing begins
-
Ventral and caudoventral blind sac
- Mixing proceeds
-
Ventral sac
- Complete mixing
- Erucation
- Rumination
12
Q
Motility of the forestomach
Erucation
A
- Gas production
- Gas consists of CO2 and methane
- Gas location
- On the top of the dorsal rumen sac
- Gas enters cardia
- Stretch receptors of the dorsal rumen sac are stimulated
- Dorsal sac, cranial and caudal ruminal pillars contract and press the gas cranially
- Reticulum dilates
-
Antiperistaltic gas transport in the esophagus
- Cardia opens reflexively - the gas gets into the esophagus
- Gas is passed towards the pharynx by antiperistalsis
- Gas leaves the rumen
- Nasopharyngeal closure
- The gas can either:
- Enter the lungs
- Gas becomes balanced with the alveolar air
- Emptied through nare
- Enter the circulation
- Enter the lungs
13
Q
Motility of the forestomach
Rumination
A
- Saliva secreted during rumination contribute to the normal amount of fluid and to the physiological pH of the reticulo-rumen
- Rumination is a reflex mechanism
- Initiated by mechanoreceptors in the ruminal mucosa in reticulum and cardia
-
Afferent fibers:
- N. vagus
- Run to the myencephalon and to the ventral area of the hypothalamus
-
Efferent fibers innervate:
- Salivary glands
- Esophagus
- Reticulum
-
Reguritation
- Bolus enters into cardia-esophagus:
- Saliva swallowing
- Inspiration with closed glottis (Müller’s experiment)
- Cardia opens reflexively
- Regurgitation contraction
-
Esophageal phase:
- Bolus squeezed
- Bolus is separated and passed further by antiperistalsis
- The bolus enters the oral cavity
- Bolus enters into cardia-esophagus:
-
Remastication
- Remastication
- Mixing with saliva
- Swallowing with saliva (2-3 times)
-
Redegutition
- Swallowing the remasticated bouls
- Bolus is mixed in the rumen
14
Q
Innervation of the forestomach motility
A
-
Parasympathetic:
- N. vagus
- Increases the intensity and frequency of the forestomach motility
-
Sympathetic:
- Plexus solearis
- Decreases forestomach motility