220 likes | 477 Views
GASTRO-INTESTINAL TRACT (Chapter 2 of text). MonogastricSimple stomach, one compartment, not capable of good utilization of forage (high fiber) dietsPig, human. . GASTRO-INTESTINAL TRACT (Chapter 2 of text). MonogastricSimple stomach, one compartment, not capable of good utilization of forage (high fiber) dietsPig, human.
E N D
1. GASTRO-INTESTINAL TRACT (Chapter 2 of text) Function
transport food
digestion: preparation of food, reduce it to utilizable form
absorption: food that has been reduced to molecular form; allows nutrients to pass through membranes to the blood stream
passive diffusion
active transport
2. GASTRO-INTESTINAL TRACT (Chapter 2 of text) Monogastric
Simple stomach, one compartment, not capable of good utilization of forage (high fiber) diets
Pig, human
5. GASTRO-INTESTINAL TRACT (Chapter 2 of text) Monogastric
Simple stomach, one compartment, not capable of good utilization of forage (high fiber) diets
Pig, human
Avian system
Crop, proventriculus, gizzard
Branched cecum
7. GASTRO-INTESTINAL TRACT (Chapter 2 of text) Ruminant
Multi-compartment stomach; has compartments for fiber digestion
Compartments are:
Rumen: large organ for microbial growth
Reticulum (honeycomb): microbial growth
Omasum (many plies): squeeze the digesta dry and send the large particles back to the reticulo-rumen
Abomasum: similar to the simple stomach
10. GASTRO-INTESTINAL TRACT (Chapter 2 of text) Ruminant, cont
Species
Cattle, sheep, goat
Deer, elk, moose, antelope, buffalo, ox, water buffalo
Reticular groove
11. GASTRO-INTESTINAL TRACT (Chapter 2 of text) Cecal fermenters
These are really a type of monogastrics which can utilize fiber due to functioning cecum
Horse, rabbit, rodents, elephant
Copraphragy
13. Organs of the GIT Mouth
Tongue, lips, teeth: essential for grasping and mastication
Difference between cattle and sheep: sheep have more agile lips and tongue
Large difference in grazing behavior
14. Organs of the GIT - mouth Teeth are very essential for proper chewing
Problems with older animals
May regulate the amount of forage an animal is able to consume
Ruminants have no upper incisor teeth; bottom incisors must mesh with upper dental pad
Distinguish difference between carnivores and herbivores
Mastication: act or process of chewing
In the ruminant mastication occurs during eating or during regurgitation = mastication
15. Organs of the GIT - mouth During mastication salia is secreted and mixed with food to form a bolus
Serous glands: thin, watery, contains amylase and buffer
Mucous glands: thick saliva, aids in food transport, hold bolus together
Sheep secrete about 4.2 gallons per day, cattle 50 gallons
Amount of secretion is mostly dependant upon chewing; diets requiring more chewing result in more salivation
16. Organs of the GIT - mouth Saliva functions:
Enzymes: ptyalin, which is an amylase, and lipase (not in ruminants)
Buffers: maintain proper pH in the rumen
lubrication
17. Organs of the GIT Stomach
Functions:
Digesta storage
Digestion
Intrinsic factor: needed for vitamin B-12 absorption
Stomach anatomy (Figure 2-4, page 9), regions to secrete:
Mucous for protection of the stomach lining against the acid stomach environment; pH of the stomach is about 2!
Secretions: intrinsic factor, HCL, pepsinogen - HCL activates pepsinogen to active form of the enzyme - pepsin
18. Organs of the GIT Sections of the small intestine
Duodenum
Jejunum
Ileum
19. Organs of the GIT –small intestine Processess of digestion and absorption in the SI
Chyme (digesta) from the stomach enter the duodenum and is mixed with intestinal juices to neutralize the acidic stomach contents (pH = 7)
Enzymes start to hydrolyze the macromolecules of the food
Intestinal enzymes
Pancreatic enzyme secretions
Bile which is produced in the liver and stored in the gall bladder is secreted into the duodenum
Emulsifies fat and aid in absorption
20. Organs of the GIT –small intestine Processess of digestion and absorption in the SI
Digesta proceeds to the jejunum: digestion continues and absorption begins as food is broken down into simple molecules
Digesta proceeds to the ileum: absorption is completed (very little absorption of nutrients after this site) and some water is re-absorbed
Process of absorption
23. Organs of the GIT Large intestine and cecum = “hind gut”
No digestion from mammalian enzymes
Microbial growth in the cecum and upper large intestine provide some fiber digestion, some B vitamin
Water and electrolyte absorption
Digesta storage