Compartment Where Regurgitation Initiates

Regurgitation initiates in-

Correct Answer: Reticulum

Regurgitation initiates in the Reticulum. During rumination, a powerful reticular contraction forces a bolus of ingesta back up the esophagus to the mouth for re-chewing.

Four Steps of Rumination

• Step 1 — Regurgitation: Strong reticulum contraction → anti-peristalsis in esophagus → bolus travels to mouth
• Step 2 — Remastication: Bolus re-chewed 40–60 seconds → particle size reduced to <1–2 mm for passage through rumen
• Step 3 — Reinsalivation: Alkaline saliva mixes with bolus (buffers VFAs, lubricates material)
• Step 4 — Reswallowing: Fine material swallowed back into rumen-reticulum

Normal Ruminal Motility

• Normal rate in cattle: 3 cycles per 2 minutes
• Each cycle: Reticulum contracts (2×) → dorsal rumen sac → ventral rumen sac → eructation

Hardware Disease (Traumatic Reticuloperitonitis)

• Metal objects (nails, wire) swallowed → settle in reticulum → penetrate wall → peritonitis
• Treatment/Prevention: Rumen magnet placed prophylactically in rumen