معده چند قسمتی

نشخوارکنندگان

حامد امینی پور Nutrit

ion

Ph.D

. Of

معده غیر ترشحیNon- Glandular Stomach

شکمبه

هزارالنگاری

Proportion of Whole Stomach Weight of Calves% ,  

 

Age (Days)

Abomasum Omasum Rumen &Reticulum

56 10 34 1

45 15 40 14

34 11 55 28

23 11 66 47

12 18 70 100

11 25 64 Adult

Swenson, M. J. 1977. Dukes Physiology of Domestic Animals.

شکمبه

شیارهای طولی

شیارهای اکلیلی

Rumen

نگاری

چین خوردگیهای الیه مخاطی

هزارال

انتقال موادغذایی با انقباض چین خوردگی ها

شیردان

گالبی شکلخمیدگیهای کوچک و

بزرگ

Tunica MucosaTunica SubmucosaTunica Muscularis

معده غده ایGlandular Stomach

نواحی و غدد معده

CardiacFundicPyloricناحیه مری

خصوصیات فیزیولوژیک سلولهای غدد معدی

Mucous Neck Cells

Chief Cells

Parietal Cells

Entroendocrine Cells

Questions

Factor of Affect on the Absorb VFA

Effect of Deleted Protozoa on the RDP

Role of Fungi on the Bio-hydrogenation

Effect Saliva on the Materials Remains

با سپاس

پایان

DIGESTA TRACT

Editor: Hamed. AminiPour

Ph.D. of Nutrition

2012

Ruminants....

100-150 L

5-8 L

3-5 LCollectively, these organs occupy almost 3/4ths of the abdominal cavity, filling virtually all of the left side and extending significantly into the right.

The rumen papillae are key to VFA absorption;health is critical

The honeycomb of the reticulum is well suited for sorting particles by size and for rumination

The folds and plies of the omasum allow ingesta to be trapped and squeezed to allow dehydration prior to delivery to the abomasum

Rumen OmasumReticulum

Ruminants: Some Basics

A. Rumination: re-gurgitation, re-mastication, re-insalivation, re-swallowingB. Eructation: 12-30 L per minute; 3-17 times per minuteC. DigestionD. Fermentation

I. Physical: 4 specialized stomach compartments

Ruminants: Some Basics

A. Cellulase complexB. HemicellulasesC. LysozymeD. Nitrogen Capture (NPN)

II. Chemical: specialized Enzymes & Processes

Because of these enzymes and abilities, ruminants can utilize feedstuffs that provide little to no nutritional benefit to non-ruminants.

Ruminants: Some Basics

A. Fiber Digestion

B. Starch Digestion

C. Urea Utilization

III. Microbial: specialized microbial population; bacteria, protozoa, fungi

Feed In

VFAMicrobial ProteinVitamins

The nutrients presented to thecow or steer by the rumen arevery different than those enteringthe rumen as feed.

Rumen Function and Development

A. The 4 compartments or four chambers:

1. Rumen: digestion and fermentation vat (VFA production)

2. Reticulum: mixing aid (feed, water, saliva)

3. Omasum: Dehydration by compression/squeezing

removes 60-70% of water from ingesta

4. Abomasum: “true stomach”; acid secretion, lysozyme

I. Organization, function, and special relationshipsamong compartments

Rumen Function and Development

1. Rumen: digestion and fermentation vat

A. conditions must be maintained to support microbial growth

1. temperature, moisture, pH buffered

2. constant supply of nutrients

3. continuous removal of products of digestion/fermentation (gases, VFA, ammonia)

Rumen Function and Development

B. products of fermentation provide bulk of energy to animal

1. Starch and cellulose digestion

2. Anaerobic metabolism (fermentation)

3. Volatile fatty acid (VFA) production

Rumen ciliate protozoa

Rumen Function and Development

C. complex polysacharides are digested to yield sugars that are fermented to produce VFA

1. Structural polysaccharides: cellulose, hemicellulose digested by cellulases and hemicellulases

2. Cellulase is not a single enzyme, but a complex (affinity factor + hydrolytic factor)

3. Protozoa engulf starch particles to digest them

4. Microbes attach to (colonize) fiber components and secrete enzymes

D. Its The VFA That Provide The Bulk Of The Energy To The Ruminant

1. Bacterial sugar metabolism differs from that of aerobic organisms.

2. VFA are produced from pyruvate by fermentation

Polysaccharides

Galactose Sucrose Fructose Maltose

Glucose

Acetate, Butyrate, Propionate

Some Basics

Digestion

Fermentation

All CHO Must PassThrough Pyruvate toBecome VFA

Some BasicsNon-structural polysaccharides Structural polysaccharides

VFA, H+

Pyruvate Lactate

Rumen pH must be defended in the face oforganic acids and H+ production to preventacidosis.

E. Rumen pH Must Be Defended1. VFAs (acids) produced must be removed

2. Passively absorbed across rumen wall

3. Helps maintain pH at 5 6.7

Some Basics

4. Saliva also provides buffering capacity

cattle: 180 L per day (70% water entering rumen)

5. Saliva is rich in Na, K, PO4, HCO3

Rumen papillae epitheliumperforms at least 3 majorfunctions:

• Protection• Metabolism• Absorption

VFA are absorbed passively; thus, the concentration gradient from lumen to blood supply must be maintained. Metabolism of some VFA within the cells of the papillae help ensure a gradient.

II. Rumen Development

A. Newborns are not functional ruminants

1. Lack sucrase

2. Limited amylase

3. Lactase: galactose, glucose

4. Ability to digest non-starch polysaccharides

precedes that for starch

Some Basics

Rumen Development Begins Early

1. Depends on:

A. Fibrous Diet

B. Inoculation

C. VFA Stimulation

Some Basics

Questions

Factor of Affect on the Absorb

VFA

Effect of Deleted

Protozoa on the RDP

Role of Fungi on the Bio-

hydrogenation

Effect of Fatty Acids on Materials Flow Rate

Effect Saliva on the Materials

Remains

THANKS

The End