C8 - The stomach of ruminants, blood supply and innervation

Question 1

The stomach of ruminants

Give the main division of the proventriculus

Answer 1

• Rumen
• Reticulum
• Omasum
• Abomasum

Question 2

The stomach of ruminants

Structures to mention in rumen

Answer 2

• Rumen (Largest compartment of the ruminant stomach)
• Facies parietalis (Facing the body wall to the left and ventrally)
• Facies visceralis (Facing the intestines, to the right)
• Curvatura dorsalis
• Curvatura ventralis
• Extremitas cranialis (Adjacent to reticulum)
• Extremitas caudalis (Blind sac)
• Atrium ruminis [Saccus cranialis] (Between reticulum and saccus ventralis)
• Saccus dorsalis (Dorsal to the longitudinal grooves)
  
  • Saccus caecus caudodorsalis (Caudodorsal blind sac)
• Saccus ventralis (Ventral to the longitudinal groove)
• Recessus ruminis (Cranial end of the ventral sac)
• Saccus caecus caudoventralis (Caudoventrall blind sac)
• Sulcus cranialis (Between atrium and recessus ruminus)
• Sulcus caudalis (Separates the caudodorsal from the caudoventral blind sac)
• Sulcus longitudinalis dexter
• Sulcus accessorius dexter (Dorsal to the sulcus longitudinalis dexter)
• Insula ruminis (Island of rumen, enclosed by the right longitudinal and accessory grooves)
• Sulcus longitudinalis sinister
• Sulcus accessorius sinister
• Sulcus coronarius dorsalis (Limits the caudodorsal blind sac)
• Sulcus coronarius ventralis (Limits the caudoventral blind sac)
• Pila cranialis (Muscular fold projecting into the cavity of the rumen between atrium and recessus ruminis)
• Pila caudalis (Between the caudodorsal and caudoventral blind sac)
• Pila longitudinalis dextra
• Pila accessoria dextra
• Pila longitudinalis sinistra
• Pila accessoria sinistra
• Pila coronaria dorsalis (Limits the caudodorsal blind sac)
• Pila coronaria ventralis (Limits the caudoventral blind sac)
• Ostium intraruminale (Opening between the dorsal and ventral sacs, bounded by the cranial, caudal, and longitudinal pillars)
• Sulcus ruminoreticularis
• Plica ruminoreticularis
• Ostium ruminoreticulare (Opening between rumen and reticulum)
• Papillae ruminis

Question 3

The stomach of ruminants

Structures to mention in reticulum

Answer 3

• Reticulum (Most cranial compartments of the ruminant stomach)
• Facies diaphragmatica (Contact with diaphragm)
• Facies visceralis (Surface towards rumen)
• Sulcus reticuli (Extends from the cardiac orifice to the reticulo-omasal orifice along the inside of curvatura minor)
• Labium dextrum
• Labium sinistrum
• Ostium reticuloomasicum (Opening from the reticulum → omasum)
• Cellulae reticuli
• Cristae reticuli
• Papillae reticuli

Question 4

The stomach of ruminants

Structures to mention in omasum

Answer 4

• Sulcus omasi (Extends from ostium reticuloomasicum → ostium omasobomasicum)
• Canalis omasi (Formed by the sulcus and the free border of the laminae omasi)
• Pila omasi (Transverse muscular pilar at the abdomasal end of the sulcus omasi)
• Sulcus omasoabomasicus (Exterior groove between omasum → abomasum)
• Ostium omasoabomasicum
• Laminae omasi (Flat parallel fold of mucous membrane extending from the curvatura towards the sulcus omasi)
• Papillae omasi

Question 5

The stomach of ruminants

Draw the stomach

Answer 5

Question 6

The stomach of ruminants

Structures to mention in abomasum

Answer 6

• Abomasum (Glandular part of ruminal stomach)
• Facies parietalis (Fascing abdomianl wall)
• Facies visceralis (Facing rumen)
• Curvatura major
• Curvatura minor
• Fundus abomasi (Dilation cranial and to the left of the ostium omasoabdomasum)
• Corpus abomasi
  
  • Plicae spirales abomasi (Large mucosal folds in the fundus and corpus)
• Glandulae cardiacae
• Glandulae gastricae propriae
• Glandulae pyloricae (Found in pars pylorica)
• Sulcus abomasi (Groove between mucosal fold along the inside of curvatura minor)
• Pars pylorica
  
  • M. sphincter pylori

Question 7

Give the composition of the stomach wall

Answer 7

1. External peritoneum
2. 3 layers of smooth muscles:
   
   1. ​External oblique fibers
   2. Circular muscle layer
   3. Inernal oblique fibers
3. Thin submucosa
4. Plexiform muscularis mucosae
5. Mucosa proper (gastic glands)

Question 8

Blood supply

1. List the blood vessels in ruminants
2. Draw the blood supply in ruminants

Answer 8

• A. coeliaca
  
  • ​A. gastrica sinistra (→ omasum & abomasum
    
    • ​A. gastroepiploica sinistra (anastamoses with a. gastroepiploica dextra)
  • A. lienalis
    
    • ​A. ruminalis dextra (runs caudally in the right longitudinal groove, anastomoses with a. ruminalis sinistra)
  • A. hepatica
    
    • ​Aa. hepaticae
      
      • ​A. gastroduodenalis
        
        • ​A. gastrica dextra (→ omasum)
        • A. gastroepiploica dextra (anasotmoses with a. ruminalis dextra)
        • A. pancreatoduodenalis
  • A. ruminalis sinistra (Follows the cranial groove between the antum and ventral sac
    
    • ​A. reticularis (→ reticulum)
• Veins runs parallel to the areries and join the v. portae

Question 9

Innervation

Answer 9

Ruminant:

• From truncus vagosympatheticus (along with esophageus)
  
  • Tr. vagalis dorsalis (→ rumen & branches to reticulum)
  • Tr. vagalis ventralis (→ abomasum & branches to omasum)
• Parasympathetic from n. vagus
  
  • ​Increases forestomac motility
• Sympathetic from plexus solearis
  
  • ​Decreases forestomach motility