Oesphagus

• What type of epithelium lines the esophagus and the four stomachs?

  The esophagus and the four stomachs are lined by stratified squamous epithelium.
• Why are viral diseases likely to affect the esophagus and four stomachs?

  Because they share similar pathogenesis and lesions with the oral cavity.
• What is hyperkeratosis and what causes it?

  Hyperkeratosis is the thickening of the keratin layer caused by vitamin A deficiency and chlorinated naphthalene poisoning.
• What is a potential complication of scar formation in the esophagus?

  A reduction in the size of the lumen, leading to stenosis.
• How can external pressure affect the esophagus?

  External pressure can cause stenosis, which may occur from a persistent right aortic arch.
• What happens when the aortic arch traps the esophagus?

  It can lead to pressure on the esophagus, causing obstruction and potential complications.
• What is a diaphragmatic hernia?

  A diaphragmatic hernia occurs when there is a weakness in the diaphragm, allowing the stomach to push into the chest cavity.
• What are some causes of esophageal obstruction?

  Stenosis, foreign bodies, and bloat can cause esophageal obstruction.
• What is megaesophagus and what can cause it?

  Megaesophagus is the dilation of the esophagus, which can occur due to stenosis or loss of neural control.
• What is achalasia?

  Achalasia is a condition characterized by the loss of peristalsis in the esophagus.
• Which breed of dog is commonly associated with congenital megaesophagus?

  The German Shepherd dog is commonly associated with congenital megaesophagus.
• What is myasthenia gravis and how does it relate to the esophagus?

  Myasthenia gravis is a neuromuscular disease that can lead to weakness in the esophageal muscles.
• What is the effect of the vagus nerve on the esophagus?

  The vagus nerve innervates the esophagus, and damage can lead to paralysis.
• What are some causes of megaesophagus?

  Causes include idiopathic innervation loss, infections, and certain toxins.
• How does a foreign body cause obstruction in the esophagus?

  A foreign body can physically block the esophagus, preventing food from passing through.
• What is ruminal bloat?

  Ruminal bloat occurs when the rumen becomes filled with gas and cannot escape.
• What are the two types of ruminal bloat?

  Primary bloat and secondary bloat.
• What causes primary bloat?

  Primary bloat is caused by fermentation of legumes and protein, trapping gas in bubbles.
• What causes secondary bloat?

  Secondary bloat is caused by obstruction or damage to the vagal nerve.
• What is the significance of the "bloat line" in bloated animals?

  The blue line indicates areas of the esophagus that are under pressure and may be compromised.
• What is rumen acidosis?

  Rumen acidosis occurs when there is an increase in volatile fatty acids and a drop in pH due to high carbohydrate intake.
• What are the consequences of rumen acidosis?

  Consequences include overgrowth of pathogenic organisms, reddening of the rumen wall, and potential dehydration.
• How can necrobacillosis develop from rumen acidosis?

  Necrobacillosis can develop when the normal flora is killed off, allowing pathogenic organisms to overgrow and invade the rumen wall.
• What are the potential sequelae of rumen acidosis?

  Potential sequelae include liver abscess formation, pulmonary embolism, and laminitis.
• What is the effect of fungal overgrowth in the rumen?

  Fungal overgrowth can lead to necrotic lesions and vasculitis in the rumen wall.
• What is the relationship between rumen acidosis and protozoa?


  Rumen acidosis can kill off normal protozoa, disrupting the rumen microflora.
• How can emboli from liver abscesses affect the lungs?

  Emboli can travel to the lungs, causing pulmonary embolic aneurysms and potential hemorrhage.
• What are the signs of pulmonary embolic aneurysm?

  Signs include bleeding from the nose and respiratory distress.
• What is the significance of infarcts in the rumen wall?

  Infarcts indicate areas of tissue death due to compromised blood supply, often from fungal invasion.
• How does rumen acidosis affect the absorption of B vitamins?

  Rumen acidosis can impair the absorption of B vitamins, leading to conditions like polioencephalomalacia.
• What is the relationship between rumen acidosis and laminitis?

  Rumen acidosis can cause vascular compromise to the limbs, leading to laminitis.
• What is the appearance of the rumen mucosa in cases of acidosis?

  The rumen mucosa appears hyperemic and reddened due to low pH.
• What are the potential outcomes of necrobacillosis?

  Outcomes include liver abscesses, thrombosis, and pulmonary complications.
• How can rumen acidosis lead to systemic infections?

  Infections can occur when bacteria from the rumen invade the bloodstream, leading to abscesses in organs like the liver.