Necropsy of STOMACH

CONTENTS

• What is stomach?

• Types of stomach

• Anatomical differences

• Pathology of stomach

STOMACH

• The stomach is a muscular, hollow, dilated part of the digestive system which functions as an important organ of the digestive tract

• located between esophagus and small intestine

– Two basics types

• Simple

• Ruminant

Types of Stomachs

• Simple Stomach

– Man, Pig

• Complex Stomach

– Cattle, Sheep, Goats

– occupies 4th of the abdominal cavity

• Simple Stomach with enlarged caecum

– Horses, Rabbits, Guinea Pigs

Simple Stomach

• Humans, swine, rabbits and horses

– Divided into three regions

• cardiac

• fundus

• pylorus

Simple stomach

Ruminant Stomach

Anatomy:

– Reticulum

– Rumen

– Omasum

– Abomasum

COMPARISION compound stomach simple stomach

4 compartments No compartments

Long digestive system Short digestive system

Prominent microbial digestion Enzymatic digestion

Can synthesis protein Can not synthesis of protein

More utilization of fibers Fiber utilization not significant

No need to provide good protein Need to provide good protein

Syntheses of vit. b No synthesis of vitamin b

Ph. 4.7 Ph. 3.2-4

Duration of digestion 4-7 days Duration of digestion is 12- 24 hours

Propionic acid is the source of energy Glucose is the source of energy

Four Components of Ruminant StomachRumen

– First part of the stomach

– composes 80% of ruminant stomach in mature bovine animals and 30% in young animals

– Papillae lining

– Storage , Soaking , Physical mixing and breakdown

– Fermentation

– Breaks down fibrous feeds into VFAs

Reticulum

• Second compartment of stomach.

• It has honey comb like structure.

• Help open and close rumen make up 5% of the stomach.

Omasum

– “Many plies”

– No enzymes from walls

– Reduce particle size

– Absorb some water

– composes 7-8% of bovine stomach

– absorbs mostly water

Abomasum

the “true” stomach

Fourth compartment of the stomach . Where true digestion occur.

composes 7-8% of stomach in mature animals and 70% in young animals

Enzymes activity break down the feed.

Avian Stomach

–Contains two parts

• Proventriculus: same as monogastricstomach and provides digestive excretions

• Gizzard: located after proventriculus, very muscular, used to grind food

PATHOLOGY OF STOMACH

Ruminal Tympany

• Ruminal Tympany is accumulation of gases in rumen

• It is also known as bloat.

• Rumen is distended due to excessive accumulation of gases

• Distended rumen compresses diaphragm to hinder

respiration.

• • Tarry colure blood, pale liver and rupture of diaphragm

• • On rupture of rumen gas comes out

GASTRITIS

• Gastritis is theinflammation of stomachin non-ruminant animalshaving simple stomachcaused by chemicals/drugs, bacteria, virus,parasite and characterizedby congestion, edema,

RUMINITIS

Inflammation of rumen in ruminant animals

caused by change in diet, chemicals or drugs

seropurulent exudate

ulcer formation.

HARDWARE DISEASE

• It is also known as reticulitis

• inflammation of reticulum

• caused by trauma/ perforation by foreign body including sharp object like needles, wires,

• Abscess formation,

• pericarditis.

OMASITIS

• Omasitis is the inflammation of omasum in ruminant animals

• Caused by Actinobacillus sp.

• Granulonatous nodules in omasum

• Typical granuloma formation

• Sulfur granules of Actinobacillus in the centre of lesion.

ABOMASITIS

• Abomasitis is the inflammation of abomasum in ruminants

• caused by chemicals/ drugs, bacteria, virus or parasites and

• characterized by congestion, edema and/ or haemorrhagic ulcers.

Stomach cancer

• Stomach cancers usually occur due to fluctuations in acidity level and may present with vague symptoms of abdominal fullness, weight loss and pain. The actual cause of stomach cancer is not known eg . squamous cell carcinoma in the stomach of a horse

IMPACTION OF RUMEN AND RETICULUM

• Impaction of rumen and reticulum is common in cattle and

• buffaloes caused by heavy carbohydrate diet and characterized

• by atony of rumen, indigestion, acidosis and haemorrhage on

• serous membranes. Atony of rumen due to lactic acid production.

• • Rumen is filled with hard, caked undigested food with

• foul odour.

Ruminal Parakeratosis

• Ruminal parakeratosis is a disease of cattle and sheepcharacterized by hardening and enlargement of thepapillae of the rumen. It is most common in animals feda high-concentrate ration. It also is seen in cattle fedrations of heat-treated alfalfa pellets etc.

• The lesions are thought to be caused by the lowered pHand the increased concentration of volatile fatty acids(VFA) in the ruminal fluid.