- father of medicine

-weight loss during fasting was due to "insensible perspiration" from skin & loss of heat

-4 elements

Fire, air, earth, water

-4 properties

Hot, cold, wet, dry

Renaissance

Leonardo da Vinic 

(1452-1519)

-Mathematician, physicist, naturalist

- No animal (whether of land or air) could live in an atmosphere which could NOT support a flame

** Antoine Lavoisier **

(1743-1794)

-Father of Nutrition

-Law of Conservation of Mass

-Named oxygen

- Combustion = oxidation

-^applied theory to animals

-1st to work w/ respiratory quotients

-1st to use environmental chamber

albuminous = proteins

oily= lipids

saccharine= carbohydrates

minerals

-fully proved 5th nutrient group: by amine compoound use to cure beri-beri(thiamin def) 

-came up with name Vitamins bc amine compounds "vital" for life 

- Refinement of nutrient requirements

-Nutrient interrelationships

-Bioavailability

-Nutraceuticals

-How to feed 9 billion people

All have

-carbohydrates

-proteins

-lipids

-minerals

-vitamins

Plants, Animals, Microbes

all have

- Glycolysis

-Kreb's cycle

-Election transport (oxidative phosphorylation) 

Require: SIMPLE INORGANIC molecules

(H2O, NO-3,SO-4,PO4)

SYNTHESIZE complex organic molecules

(carbs, lipids, proteis) 

use PHOTOSYNTHESIS

(6CO2+6H2O)=C6H12O6+6O2

-use COMBUSTION (OXIDATON) for energy

-reverse of photosynthesis to get ATP

C6H12O6+6O2=6CO2+6H2O+Energy(ATP)+ HEAT

-"Self Feeders"

-higer plants

(those that carry out photosynthesis)

-"one that feeds"

-Animals

-Fungi

-Most bacteria

if they can not, can not support:

-growth

-maintenance

-work

-production ( milk, eggs)

Metabolism

(anabolism+catabolism)

BUILDING UP of body tissue and chemical components

-NET gain in body tissue

TEARING DOWN of body tissue and chemical components

-losing of body tissue

-Glucose

-amino acids

-minerals & vitamins

Essential

(Indispensable Nutrients)

NON-essential

(dispensable nutrients)

-Alimentary canal

-Flexible muscular tube

-continuous from MOUTH to ANUS

-highly selective

-Storgae

-prepare food for absorption

-reject undigested residue

-**Fermentation**: takes place PRIOR  in RUMINANT

AFTER in horses

prehension: obtaining food(getting in mouth);using lips, teeth, tongue 

mastication: chewing (the breaking up of food)  

deglutition: process of swallowing (involuntary reflex) 

regurgitation: bring food back to mouth ; *important for ruminants*- not possible for horses

Saliva

Parotid: watery saliva

Sublingual & Submaxillary: mucus like saliva

- a muscular tube connecting the mouth to the stomach

- "peristalsis"

-deglutition

-Cardiac sphincter

-separates esophagus from stomach (helps prevent acid reflex/heart burn)

-species dependent; some dont have

Functions:

-storage

-mixing (food + gastric secretions="chyme")

-Empties @ a controlled rate

-chemical & enzymatic dig ( HCl, Pepsin, Rennin)

-Bacteriostat (pH~2)

What stimulates gastric secretions? (HCl +pepsinogen)

GASTRIC SECRETIONS --> Stimulus:

-smell, taste, thought of food

-**GASTRIN**: hormone released;most powerful stimulator

-Acetylcholine

-Histamine

-Protein (pepsin stimulates)

-Acid

-Antihistamine

-**CCK**: hormone released; primary inhibitor

-Fat

-OTC products

-Osmotic Pressure

Regulation of stomach

pH (1.5-2.0)

1.) Food enters stomach (stimulates muscle contractions) -->

2.)Stomach wall secretes gastrin hormone into blood -->

3.) Stomach glands secrete HCl -->

4.) Acid stops gastrin secretion (pH is now 1.5)

-on left side of animal

-site for MICROBIAL fermentation

-4 distinct compartments

RUMEN

(paunch)

-epithelial lining

-numerous papillae that vary in shape, size, 

Reticulum 

(honeycomb)

-epithelial lining

-thrown into folds that form polygonal cells that give it (honeycomb look) 

Omasum

(manypiles)

-epithelial lining

-thrown into broad longitudinal folds 

-some times referred to as book

-allows ruminants to consume, LOW quality, FIBROUS feeds; which would not otherwise support life

-makes them LESS dependent on diet vs non ruminants

MICROBIAL POPULATION: microbes digest 70-80% of the dry matter intake of ruminant

-primary digestors of what we feed them; then convert into something usable for animal

-bacteria 

-Protozoa

-Yeasts

- frequent food intake

-constant temperature

-constant pH

- **removal of end products (so theres no build up of microbial products)

-similar osmotic pressure to blood

-**dynamic environment and very powerful

(b/c moving about 400lb of material)

-esophageal of reticular groove (nursing calf- bypasses rumen str8 to true stomach)

-rumination (chewing of cud)

-eructation (removing of gas)

Regulation of stomach emptying

(NON ruminant & ruminant)

1.) pylorus opening; pylorus relaxes -->

2.) Acidic food slips through -->

3.) Acid entering SI causes Pylorus to close -->

4.) Pylorus reopens when acidic chyme is neutralized -->

-Bicarb (CHO3-): secreted by the pancreas

-stimulated by Secretin (hormone)

Small Intestine

(small bowel) 

-long tube for digestion & absorption of nutrients (pH 6-7)

-**main site for enzymatic digestion & absorption

-SI lining must be healthy --> enteritis 

- 3 parts - each roughly 1/3 of SI

-length

-folds

-villi & microvilli: increase SA; tremendous turnover rate; basically new SI lining everyday

-circular & longitudinal muscles

main movement of SI

-(squeeze in the middle but ultimately make it move to-->)

Large Intestine

(large bowel)

-absorbs H2O and electrolytes

-storage of feces until it is expelled out the anus

-bacterial action

-hind gut:important in the horse, rabbit, and elephant

-humans dont have one have appendix 

ascending (up),transverse (side) and a descending (down) colon

-no cecum 

Pancreas

(lies w/in DUODENUM Loop-middle of it)

1.) Stimulus (acid chyme from stomach)-->

2.) Secretin (hormone) released from S-cells of SI-->

3.) Secretin travels through blood to the pancreas-->

4.) causes pancreas to release bicarbonate (CHO3-)

inactive forms

a.) Proteases :  digests proteins

b.) Amylases: digests starch

c.) Lipases: digest lipids

-responsible 4 blood glucose levels

insulin: causes blood glucose levels to DECREASE

glucagon: causes blood glucose levels to INCREASE

normal blood glucose level = 90-110

Pancreatic Functions:

Endocrine : (insulin & glucagon)

-insulin - released from BETA cells

-glucagon- released fromAPLPHA cells

Exocrine: (enzymes + bicarbonate)

Liver

(waste stream)

- FAT in chyme causes release of **CCK**--> travels in BLOOD to --> gall bladder --> contracts releasing BILE

-continuously secretes bile

-composed of water, phospholipids, bile acids, cholesterol, BILIRUBIN

-bile acids synthesized from CHOLESTEROL (Taurocholic and Glycocholic) HDL(good) LDL(bad)

-liver can create grams of cholesterol if not in diet

1.) pigment stones: calcium salt of unconjugated bilirubin (normally conjugated w/ glucuronic acid)

2.) Cholesterol stones: most common (50-70% cholesterol) 

-Gluconeogensis

-Fatty acid & lipoprotein synthesis

-Glycogen synthesis (storage & breakdown)

-Storage of fat-soluble vitamins

-Detoxification

-numerous Enzymes produced

-Distribution center

-PROTEINS that are capable of catalyzing a specific chemical rxn

-very sensitive to HEAT & pH change

(changes shape of enzyme = will not function)

- All enzymes are PROTEINS

- They INCREASE (speed up) the chemical rxn

-Most end in -ASE

-Many enzymes can act alone, however several require a Cofactor

-Enzymes are sensitive to temp and pH 

- Metal Ions: Mg, Zn, Cu, Fe, Mn

- coenzymes: Complex organic molecules; water soluble vitamins

-Enzyme w/ cofactor: Holoenzyme

-Enzyme w/o cofactor: Apoenzyme

-A physiological, organic, chemical substance, synthesized and secreted by specific ductless glands from which it is directly transported to blood or lymph systems and carried to another part of the body where they modify the actions of specific target tissues and organs

Hormone Functions:

-homeostasis

-Respond to emergency demands (stress, trauma )

-integration of Growth (Growth and Development of Skeleton, muscles, etc)

-regulation of sexual reproduction

Hormone 

categories

1.) Polypeptides

2.) Steroids

3.) Phenolic Amines

Polypeptides

(Glycoproteins)

1.) yield amino acids (3-1000)

2.) Synthesized in: 

-BRAIN: hypothalamus, anterior & posterior pituitary, 

-Pancreas, thyroid, gut

-REPRODUCTIVE SYSTEM : placenta, ovary, testis

3.) examples: insulin, gastrin, secretin

- originate from cholestrol

- synthesized in :

ADRENAL CORTEX

EMBRYONIC MEMBRANES

REPRODUCTIVE SYSTEM: ovary, placenta, testis (estrogen, testorone)

-synthesized in:

Thyroid: T3, T4 ( t3 has 3 iodine molecules, t4 has 4 )

Adrenal Medulla

Pineal 

-works through receptor sites at the cell

- different locations for different types of hormones

phenolic

MUST QUICKER THAN OTHERS

-large protein molecules w/ high specificity and affinity(tight bond)

-2 parts: 

-enzyme activation, ion channel, transport protein

-once hormone binds to receptor- something biological happens

proteins= turn something on

thyroid vs sterioid: thyroid happens sooner, steroid delay in response 

Ribusco 

(Ribulose 1,5 Diphosphate Carboxylase )

-enzyme that adds a carbon to a 5 carbon sugar to get a 6 sugar caron

Feed

water              dry matter

organic matter                                Ash(minerals 

Nitrogenous substances        Non-nitrogenous substances

True Protein Non-nitrogenous subs      carbohydrates  Fats      

                                      soluble (NFE)  Insoluble (fiber)

NFE = 100-(moisture+ash+CP+EE+CF)

-NFE is determined by difference, NOT product of a direct chemical or physical assay