Intro to Nutrition Flashcards
nutrition
the study of the body’s need and mechanisms of acquiring, digesting, transporting, and metabolizing nutrients
feed costs can exceed 70% of animal production
monogastric
human pig dog cat
simple stomach
dietary components broken down and absorbed in small intestine
ruminant
cattle sheep goats moose giraffe etc.
herbivorous diet in general
rumen contains microbes that degrade feed
-fermentation energy products absorbed here
microbes then passed into abomasum
final digestion and absorption in sm. intestine
hind gut fementation
microbes in hind gut break down forage
fermentation products absorbed for energy
nutrient
a substance in the diet that supports normal functions of the body 6 major components carbohydrates protein lipids vitamins minerals water
feedstuff components
water (moisture) protein (crude protein) fat (crude fat) carbohydrates vitamins minerals (ash)
energy NOT a nutrient
dietary essential nutrients
must be part of the animals diet
ex: essential AA, some vitamins, some minerals
species specific
50 for most monogastrics
-cant be made at all or in sufficient quantities by the body
deficiency = disease or decreased performance
nutrients are energy sources
generate energy via metabolism to generate ATP
measures of nutritional energy
calorie (cal) amt of heat to raise 1g water 1degC
nutritionalists calorie is actually a kilocalorie (kcal)
water
obtained from food, beverages, metabolism (formed during chem rxn)
excreted via kidney, skin, intestines
functions: lubrication, cooling
carbohydrates
important source of energy 4 kcal/g
chemically CHO
glucose, simple sugars, complex carbs
deficiency - no specific requirement but will be manifested as an energy deficiency
excess - deposited as fat in adipose tissue
glucose
6 carbon sugar the bodys major energy source primary fuel of metabolism - only source of food for brain limited body reserves in form of glycogen -chains of glucose in liver and muscle excess glucose converted to body fat large increase in glucose requirements in late pregnancy and lactation
monosacchardies
hexoses 6 C
glucose - blood sugar
galactose - part of lactose
fructose - part of sucrose
disaccharides
sucrose - table sugar
-glucose and fructose
lactose - milk sugar
-glucose and galactose
polysaccharides
polymers of glucose
starches
fiber
cellulose
starches
mostly alpha 1-4 linkages between glucoses
storage form of energy
plant - amylose, easily digestible
animal - glycogen
fiber
major components of plant cell walls
structural components of forages
termed non digestible
celulose
plant cell wall
gives rigidity
animals lack cellulase enzyme required to break beta 1-4 linkage
can be hydrolyzed in rumen
microbial fermentation
celulose –> glucose –> VFAs
products are short chain volatile fatty acids
acetate, propionate, butyrate
these are absorbed where they are produced
lipids
fats
9 kcal/g
made up of fatty acids (long medium and short chains of C)
fat is stored as triglyceride (glycerol and 3 fatty acids)
required for cell membranes (phospholipid bilayer)
deficiency - scaly skin, tail necrosis, growth and reproductive failure
excess - obesity, health problems
essential fatty acids
linoleic (18:2) and linolenic (18:3)
required for membrane, prostaglandin, hormone synthesis
plentiful in plant materials, fish oil, and animal fat
saturated fatty acids
solid at room temp
animal fats such as butter
unsaturated fatty acids
liquid at room temperature
ex veg oil
protein
synthesized in animal form
-AA from diet and synthesized in body
whole proteins not absorbed broken down into AA that can then be absorbed
long chains of AA
amino acids
20 different AAs characterized by 3 components 1. an amine group - NH3 (nitrogen) 2. a carboxyl group - COOH 3. an R group - specific for each AA
peptide bonds
AAs joined together by peptide bonds
- 2 AAs joined H2O molecule removed
AA composition of protein controls folding and function
essential amino acid
must be provided in the diet
non-essential amino acid
animal can synthesize or make from other AA
semi essential amino acid
rate of synthesis is too low to meet demand
first limiting amino acid
essential AA in least concentration in diet relative to animals needs
all AA must be present in diet for normal protein synthesis
amino acid deficiency
poor growth rate reduced intake low birth weight and high infant mortality reduced milk and egg production infertility
non protein nitrogen
ruminant bacteria can use NPN to make AA NPN: AA nucleic acids (DNA, RNA) Ammonia (NH3) urea
minerals and vitamins
key factors in metabolism enzyme cofactors (catalysts)
vitamins
organic components of feedstuffs that are required in minute quantities for a specific function
some species are able to synthesize some vitamins or utilize vitamins that are microbially synthesized
fat soluble vitamins
some storage in body fat
A, D, E, K
water soluble vitamins
limited body storage
vitamin C
B vitamins
function of vitamins
biochemical reactions - cofactors -such as B vit folate antioxidants - vit E and C vision - vit A structure - vit D blood clotting - vit K
vitamin D
bone growth
reproduction
vitamin E
immune function
reproduction
vitamin A
vision, bone growth
vitamin B
growth, anemia
vitamin C
scurvy
in guinea pigs causes scaly bleeding skin
minerals
inorganic elements - on periodic table
macro: Na, Ca, Cl, Mg, P, K, S
- 100’s of mg to gm range
micro: Cr, Co, Cu, F, Fe, I, Mn, Mo, Ni, Se, Si, Zn
- ug to 10’s mg range
function of minerals
most minerals may have many functions
structural (bone, egg shell) - Ca, P
biochem rxn (catalyst coenzyme) - P, Fe
nervous/ muscular system activity Ca, Na, Cl
regulation of osmotic pressure and pH (acid and base)
mineral deficiencies
calcium - osteomalacia
- milk fever
Iron - anemia (component of hemoglobin)
Iodine - goiter (thyroid hormone component)
milk fever
excessive loss fo blood Ca in early lactation
hypocalcemia
goiter
iodine deficiency
extensive growth of thyroid gland due to over compensation
osteomalacia
rickets
soft bones
bowed legs
