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Diseases of the stomach

Gastric dilation

Dilation of the stomach ( abdomen ) is accompanied by:

- Severe abdominal pain.
- Projectile vomiting.
Etiology:
1-Sudden & complete obstruction of the pylorus by foreign body (Hair balls).
2- Gross overeating (grain engorgement ) or drinking.
3- External compression by lipoma in horses.
4-The condition may occur in old debilitated animals fed for long periods on indigestible
roughages
5-Wind-sucking in horses.
6- Acute idiopathic dilation after racing.

Pathogenesis:

1-Dilation of the stomach stimulates vomiting with consequent increase in gastric motility
leading to powerful peristalsis towards the pylorus causing pain.


2- Reflex depression of the cardia and peripheral vascular system results in the occurrence of
shock and their may be a reflex depression of respiration.
3- Local damage to gastric mucosa may cause additional shock.

4- Excessive secretions & loss of fluids causes fatal dehydration and alkalosis.

5-Increase permeability of mucosa to byproducts produced by putrefaction causes toxemia.
6-Rupture of the stomach may also occur.

Clinical findings

1-Vomiting is a cardinal signs in acute gastritis. Vomiting is usually projectile in nature.(In the
horse vomiting materials may come form the nostrils (terminal event) followed by rupture.)
** In case of grain engorgement in horses vomiting does not occur as grain absorb much of
fluids.
2- Abdominal pain is severe in horse. This is manifested by:
Sweating , rolling, kicking at the belly, sitting on the hunches. The dog sitting in horses helps
the animals to relief pressure on the diaphragm to facilitate breathing.
3- Dehydration, looseness of the skin elasticity sunking of the eyes.
4-When the alkalosis develops the signs are tetany, tremors and rapid shallow respiration.
5- Pulse rate is increased (rapid and progressive).
6- Passage of stomach tube results in evacuation of a large quantities of foul smelling fluid.
7-In chronic dilation there is anorexia, mild continues or current pain scanty faeces, loss of
weight, occasional vomiting after feeding and moderate degree of dehydration.
8- If rupture has occurred, vomiting ceases, the animal stands quiet, cold, sweating tremors
occurs, subnormal temperature and severe congested m.m., pulse reaches 120/m and is very
weak. Peristalsis are absent.
Lab. diagnosis:
1- Examine the vomitus to determine the origin and nature of the contents.
2- X- ray exam. may be of value in young animals.


Treatment:
1-Sedate the animal by giving 30-40 gram chloral hydrate i/v or orally by a stomach tube.
2- Evacuation of the stomach by the aid of a large stomach tube could, he tried and in most
cases is unsuccessful.
The procedure is done by pumping 1-2 gallons of normal saline then siphoned out. The
difficulty is met with when there are grains.
3-Another trial is the administration of mineral oil (one gallon) or 2 liters linseed oil followed by
a parasympathetic stimulant. There is a danger as this latter drug may cause rupture of the
stomach.
4- It is preferable to keep the animal in the standing position to prevent rolling otherwise torsion
is likely to occur.
5- Periodical removal of gastric fluid may relief discomfort, but in this case i/v administration of
electrolyte solutions is necessary.
6- Repeated administration of belladonna preparations may help in relaxation of the pylorus.
Horses: 30-60 mg S/C two to four times daily.
7-Gastrotomy is advisable in young animals when physical activity due to tumors or foreign
bodies are in the suspect
8- Chronic atony may be treated by administration of: oral /14 ml tincture of Nux vomica given
twice daily.
9- You can give orally salicylic acid 15-25 gr. (Large animals) to control fermentation.

Gastric ulcer

Definition:
Ulceration of the gastric mucosa is characterized by anorexia, abdominal discomfort; intestinal motility giving rise to either constipation or diarrhoea and in some cases gastric hemorrhage.

Etiology:

Gastric ulcers in farm animals are usually traumatic or it may result from the following causes:
1- Light feeding on corrosives or chemicals for a long time, which will cause shallow erosion
giving rise to ulcers.
2- Neglected cases of gastritis.
3- Tumors of the stomach may lead to ulcers.
4- Due to long standing parasitic infection in the stomach such as Gastrophilus species
( botflies ) or Habronema megastoma.

Pathogenesis:The effects of gastric ulcers are largely reflex causing spasms of the pylorus and
increased gastric motility.
Symptoms:
1-In uncomplicated cases, there are mild and intermediate signs of abdominal pain, anorexia and
either constipation or diarrhoea.
2- In vomiting animals, vomiting occurs and the vomitus contains mucous and is not high
acidic.
3-Haemorrhage may occur ,giving rise either to severe hemorrhagic anemia
4-The faeces are black in color, usually pasty in consistency and of small volume due to the
accompanied spasms.
5- In the complicated cases, there is perforation of the stomach to rupture or severe
hemorrhage of the stomach.
Treatment:
1- Protective and astringent drugs are used (as in gastritis) and recommended for longer periods.
2- If hemorrhage takes place and is severe, blood transfusion or haematinie drugs are useful. In
addition give anticoagulants as injections of calcium and vitamin K.
3- Food containing irritant materials should be avoided.
4- Surgical repair is useful.


Gastritis
Definition:
Inflammation of the stomach causes abnormal motility and it is manifested clinically by vomiting. This might be acute or chronic & is commonly associated with enteritis in the syndrome of gastroenteritis.
Gastritis in horses is uncommon, except for those associated with gastric ulceration and parasitic causes.
Etiology:
The inflammation may be caused by:
1- Physical agents:
Grass over-feeding causing gastric dilation and is usually accompanied by secondary gastritis.
b) Ingestion of coarse fibrous feeds as straw bedding or bad teeth leading to faulty
mastication has the same effect.
c) Damaged feeds, mould & fermented hay cause moderate gastritis.
2-Chemical agents:
Caustics, irritant poisons (arsenic, lead, copper, mercury and phosphorus nitrate) cause severe gastro-enteritis.
3-Bacterial agents:
Examples: Salmonellosis .
4- Metazoan agents:
Horses: Larvae of Habronema megastomum cause ulcerative lesions of the stomach which lead
to perforation.
Pathogenesis:
Inflammation of the stomach may be either:
1-Acute reaction where increased motility causes pain ,increase peristalsis) with rapid
emptying of the stomach by vomiting or via the pylorus in animals which do not vomit.
2-Chronic reaction causes increased secretion with delayed food indigestion which permits
putrefaction and leads to further inflammation of the intestine.
Clinical findings:
Acute gastritis:
1-Vomiting: The vomitus contains much mucous, may be tinged with blood. Repeated vomiting
is accompanied by retching movements.
2- The appetite is always reduced or absent.
3- Excessive thirst.
4- Breath has a rank smell.
5- Diarrhoea is present, then there is gastro-enteritis.
6- Faeces are pasty and soft.
7- Signs of the primary disease.
8- Dehydration & alkalosis with tetany & rapid breathing may develop if vomiting is excessive.
Chronic gastritis:
1- Signs are less severe with depraved appetite.
2- Vomiting occurs sporadically (after feeding) the vomitus contains viscid mucous.
Diagnosis:
1- Gastritis & gastric dilation have some similarities. In the latter the vomitus is more profuse
and more projectile.
2-Oesophageal obstruction: vomitus is not acid or rancid.
3-Intestinal obstruction: always contain bile and alkaline in reaction.
Treatment:
Treat the primary cause.
Many preparations could be prescribed.
1 - Gastric sedatives: Preparation of: - Magnesium hydroxide. - Magnesium carbonate
- Kaolin-Pectin-charcoal. - Bismuth or carbonate.
2- Gastric asthrgents: Tannic acid.
3- Fluid therapy:
To replace the electrolytes lost by vomiting. (These electrolytes are Na, K, Ca, Mg.). These
are given by I/v. and orally when vomiting stops.
4-Some chemotherapeutic drugs and antibiotics are also prescribed as sulphaguanidine.
5- If purgatives are used to empty the alimentary tract use mineral oil to avoid further irritation
by other purgatives.
6- During convalescence, give the animal soft, highly nutritional feed.
7- Alimentary tract stimulants as strychnine preparations , ammonium carbonate to be quick the
return of gastric motility.
8- Vitamin B6 in a dose of 50-100 mg every other day.