7

Diseases of the esophagus

Oesophagitis

Inflammation of the esophagus which is accompanied by signs of:

I- Spasms and obstruction.
2- Pain on swallowing and palpation.
3- Regurgitation of blood-stained slimy materials.
Causes:
1- Ingestion of chemicals or irritant materials.
2- Laceration of the mucosa by foreign bodies as uses of large stomach tube.
3- Death of Hypoderma lineata in the submucosa of the esophagus causes acute
local inflammation.
4- Secondary to some infectious diseases such as(mucosal disease, malignant
head catarrh .
Pathogenesis:
Inflammation leads to an increase in muscle tones and involuntary movement with local edema and swelling leading to functional obstruction.
Clinical findings:
1- Salivation and attempts to swallow which cause severe pain particularly in
horses.
2- Regurgitation of food mixed with fresh blood and mucus, coughing, retching
movements, with vigorous contraction of cervical & abdominal muscles.
5- Perforation of the thoracic esophagus leads to fatal pleurisy.
6- Signs of viral diseases) where the lesions being mainly erosive.


Treatment:
Food should be stopped for 2-3 days and intravenous injection of glucose should be supplied.
2- Parentral antibiotic administration especially if laceration or perforations occurs.

Oesophageal obstruction

Oesophageal obstruction may be acute (chock) or chronic. The major clinical signs are:
1- Inability to swallow.
Regurgitation of food and water.
continuous drooling of saliva,
Bloat in ruminants.
Horses with choke commonly regurgitate feed and water and drool saliva through the nostrils because of the anatomical characteristics of the equine soft palate.

Causes:

Obstruction may be intraluminal by swallowed material or extraluminal due
to pressure on the esophagus by surrounding organs or tissues.

Intraluminal obstructions: These are usually due to ingestion of materials that are of inappropriate size and that then become lodged in the esophagus:
Solid obstructions, especially in cattle, by turnips, potatoes, peaches, apples,
oranges, etc.


The most common type of esophageal obstruction in horses is simple
obstruction due to impaction of ingesta .

A trichobezoar caused esophageal obstruction in a cow.

Extraluminal obstructions

Tuberculous or neoplastic lymph nodes in the mediastinum or at the
base of lung
Cervical or mediastinal abscess.
Esophageal paralysis.

Pathogenesis:

Physical inability to swallow and prehension.
Eructation which leads to bloat.
Clinical findings:
Acute obstruction or choke:
Cattle:
1- The site is usually in the cervical esophagus just above the larynx or at the thoracic inlet.
2- Animal stops eating and shows anxiety and restlessness.
3-Forcible attempts to swallow.
4- Salivation-coughing-continuous chewing movements,
5 - Incomplete obstruction with bloat.
6- Ruminal movements are continuous and forcible.
7- Systolic murmurs are heard on heart auscultabon.
8- Passage of stomach tube is impossible.
9- Acute signs may subsides within few hours due to relaxation of the oesophageal spasm, but tympany persists. Many obstructions may pass spontaneously, other may persist for several days.
Horses:
Site:
Obstruction is often in the terminal part of the thoracic esophagus and cannot be seen or palpated.
Clinical signs:
-Like that of cattle in general, but in horses it takes a violent picture.

-Death may occur in either species due to aspiration pneumonia and dehydration.


Chronic obstruction:
1- Absence of acute signs.
2- Chronic bloat which persists for very long period .

Treatment:

1- In acute obstruction sedate the animal at first by any ataractic drug or chloral hydrate may help to relax the oesophageal spasm or the use of other relaxants such as: Atropine sulphate (16-32 mg \ kg body weight).
2- Passage of stomach tube to locate the obstruction.
Gentle attempts may be made to push the obstruction onward avoid damage of the
oesophageal mucosa.
3- In cattle where solid obstruction is in the upper esophagus, you can reach it by passing the hand or large forcipes into the pharynx through a speculum and by the help of an assistant to push the foreign body upward. A wire bent as a loop may help also to pull the object upward. In cattle you have to watch tympany. In emergency cases trocar the rumen and leave the cannula until obstruction is relieved. If all these fail to pull it out, leave the animal for a while and apply relaxants for the esophagus.
Horses:
1- Some difficulty is met with in removing those materials which accumulate in the lower esophagus in horses. In this case, small quantities of warm saline are introduced through a stomach tube that passed to the site of obstruction-then the saline is pumped or siphoned out. Repeat this several times until fluid comes clear. If obstruction is still present fluid extract of belladonna should be administered before removal of the tube. Further attempts could be made at shorten the intervals but avoid aspiration pneumonia.
2- In case of a palpable obstruction in the neck vigorous squeezing from exterior may brake it up and aid in its removal.
3- Surgical removal by oesophagotomy may be necessary if other measures fail. Treatment of chronic obstruction is usually unsuccessful.
Complications
1-Suffocation, asphyxia and death.
2-Subcutaneous emphysema if the obstructive material causes perforation of the esophagus.
3- unrelieved choke may lead to fatal paralysis and necrosis of the esophagus.
4- Death may take place from drenching pneumonia which arises from the passage
of the saliva to the respiratory tract.
5- Tympany appears and will be severe one if there is complete choke.