Lecture 5 Flashcards
Importance of knowledge of the GIT
Influential for food/nutrient utilization.
Functions of Organs, Glands, & Specialized Structures of the GIT system
Procurement, chewing, & swallowing.
Digestion/absorption of nutrients.
Secretory/excretory functions.
Ultimate Goals of GIT
Efficient assimilation of nutrients.
Rejection of harmful constituents.
Digestion definition
Preparation of food for absorption.
Mechanical forces of digestion
Mastication, swallowing, peristalsis.
Chemical forces of digestion
Hydrochloric acid, microorganisms, bile.
Mastication
Chewing, breaking down, coating with saliva.
Peristalsis
Muscular contraction of intestines.
Processes of absorption
Passage of small molecules from GIT to blood/lymph.
Considerations if absorption
Variation in structure/function.
Symbiotic microorganisms.
Carnivores - Non-ruminants
-Primarily non-plant material.
-Concentrated, highly digestible diet.
Carnivores - GIT
Gastric stomach.
Short, uncomplicated intestine.
Hind gut fermenters.
Examples of Carnivores
Dogs & cats
Non-ruminants - Omnivores
Plant/animal protein diet.
Modified GIT for plant tissue utilization.
Examples of Omnivores
Pigs & rats
Herbivores diet:
Fibrous plant material.
Examples of herbivores
Cows, horses
Important differences of herbivores
All ruminants are herbivores, not vice versa.
Mouth & Associated Structures of Non-ruminant species
Used for grasping/masticating food.
Saliva aids in digestion.
Saliva
Breaks down starch.
Cleans mouth, fights microorganisms.
Esophagus function
Transports bolus to GIT.
Stomach (Non-Ruminant) shape/size
Varies by species.
Stomach (Non-Ruminant) Non-glandular region
entry site for esophagus. No digestive secretion/absorption
Stomach (Non-Ruminant) Glandular regions
Cardia: Mucus production.
Fundus: Rugae, gastric pits, various cells.
Pylorus
Digestive Process
-Presence of food triggers HCL and enzyme secretion.
-Mucin prevents self-digestion.
-Forms chyme.
Small intestines:
Primary Site for Enzymatic Digestion
Villi for absorption.
Sections of small intestines
Duodenum, Jejunum, Ileum.
Duodenum
Neutralizes chyme (6.8-7) with bile salts.
Pancreatic enzyme secretion. Protein, carb, and fat digestion
Jejunum & Ileum
Primary sites for nutrient absorption.
Large Intestine is the Primary Site for Microbial Digestion
Absorption of water and organic compounds.
Elimination of undigestible components.
Large Intestine Sections:
Cecum, Colon, Rectum.
The avian species have no teeth
Beak/claws reduce food size.
Swallowed feed goes to crop.
The stomach is replaced by what in avian species?
Crop, Proventriculus, Gizzard.
The crop:
Temporary storage.
Great capacity for expansion.
Proventriculus:
Gastric secretions produced.
Gizzard
Muscular grinding.
Small Intestines of avain’s
Enzymes, acidic pH, water absorption.
Cloaca
Single duct for urine & feces.
