water and protein topic 2 Flashcards
What is food?
material which after ingestion is capable of being digested, absorbed and metabolised
define ingestion
process of taking food into your body
define digestion
process of breaking down larger molecules in food into smaller ones capable of being absorbed across the GIT
define absorption
process of absorbing the end product of digestion across the GIT
define metabolism
process whereby absorbed nutrients are utilised to meet the animals requirements for energy, protein etc.
what are the 2 major components of food?
draw the nutrients in feed diagram
food= water and DM
DM= organic and inorganic
organic= carbs, lipids, proteins, vitamins
why choose a feed sample of 10% water over a 50% water?
has less water content so hence a higher DM (90%) content, be of greater nutrient value
define organic matter
carbon based
why is water important?
60-70% of animals body, essential for bodily processes
what are 5 functions of water?
solvent, in metabolic processes (sweat), transport, tissue fluid and saliva
what are the 3 major sources of water?
metabolic water, drinking and food
what are the 2 types of water loss, give an example of each
sensible losses
- urine, faeces and sweat
insensible losses
- respiration
why is there a variation for water requirements in animals?
heat production (increases requirements) feed intake (increase in intake, increase in water req) salt accessibility quality species physiological stage (e.g. lactation) enviro adaptations
what are 3 things to consider when assessing water quality?
potential toxins
excess solids
chemical residues
list the steps nutrients in feed must go through to be useful to the animal
ingestion-
taking food into the body
digestion-
breaking down larger molecules into smaller ones capable of being absorbed
absorption-
absorbing the end products indigestion across the GIT
metabolism-
absorbed nutrients are utilised to meet animal requirements
what compounds can be potentially toxic to animals if drunk?
blue-green algae, nitrates, fluorine
why are proteins important?
essential to life, major part of all living tissue
what are the 4 main functions of proteins?
immunity (immunoglobulins) structural (hair) metabolism (enzymes) potential energy source (not efficient)
where do proteins come from?
diet
what makes up proteins?
aa
what is the basic structure of an aa?
amino group (NH2)
carboxyl group (COOH)
central carbon
r group
what is an essential aa, list them (10)
animal cannot syn
arginine histidine isoleucine lysine leucine methionine phenylalanine threonine tryptophan valine
where are proteins digested in monogastrics and ruminants?
SI and
rumen microbes then finally by animal in SI
what form of proteins are absorbed into the blood across SI wall in mongastrics?
aa and dipeptides
what breaks down proteins in the stomach and SI?
stomach
HCL and pepsin
SI
trypsin, chymotrypsin, peptidases
what is the limiting aa?
the first limiting aa is most likely to be limiting
what is biological availability of protein?
not all ingested proteins are accessable to the animal, those that are are considered biologically available
what determines the protein requirements of a mongastric?
age - higher demand in young stage - lactating and pregnant maintenance -has lowest requirements
why does the digestion of proteins differ from mongastrics?
presence of microbes, modifying affect of rumen
what is the role of microbes in ruminant digestion of protein?
they have 1st access before SI
enzymes they secrete break down proteins into ammonia and some aa which they use to build proteins for themselves
microbes die, wash to SI
microbes digested by animal, then absorb aa through SI
what is MCP?
microbial crude protein, ruminants absorb most protein though microbes.
this gives its measure
what is UDP? when would be the advantage of increasing this? (ruminants)
undegradable dietary protein,
protein that escapes microbial digestion in rumen. can do this by heating feed or adding chemicals (formaldehyde)
usually MCP enough, but in high producing cows (milking) may need to increase UDP
what us NPN?
non protein nitrogen
e.g. urea
microbes need N so they can synthesise protein, feed NPN to increase protein in ruminant
little affect on monogastrics as the cannot use NPN
draw a flow diagram of protein digestion in ruminants
page 48 study guide
what are the ruminant protein requirements?
don’t have essential aa to same extent as monogastrics, microbes syn
what is crude protein?
includes all N sources in feed (protein and non protein)
how is crude protein calculated?
total N content X 6.25
when is urea used?
to increase crude protein uptake in ruminanants
crude protein = 281%
(45% N X 6.25)
shouldn’t feed as more then 1% of diet- too much = rapid build up of ammonia = toxic
what is urea poisoning and how can it be avoided?
too much urea in diet =rapid build up of ammonia = toxic
avoided by introducing slowly feed at low levels mix thoroughly (no big clumps) use blocks/open feeders (access at lib)
define protein quality
dietary proteins containing essential aa at the level needed by the animal = high quality proteins
what regulates absorption of water?
osmotic pressure
what are the 2 protein classes give examples
simple
- only aa
- either fibrous structural role e.g. collagen
- or globular
e. g. albumin
conjugated
- contain non protein groups
- glycoproteins
- lipoproteins
what are the 5 types of N compounds
nucleic acids amines amides nitrates alkaloids
what are endopeptidases and exopeptidases?
o Endopeptidases
Break proteins at internal points along AA chains
Produce essentially no free AAs
o Exopeptidases
Release individual AAs from ends of peptide chains
what are zymogens?
digestive enzymes released from stomach or pancreas in the inactive form
