L7: Water and Protein Flashcards
_*Describe the factors affecting water requirements_
- Heat production/ambient temperature
- Feed intake
- quality and type
- Salt
- level
- Accessibility to water source
- travel distance
- Water quality
- turbidity, salt etc
- Species
- Physiological state
- Environmental adaptation
Define essential amino acid and list examples
An essential aa must be obtained from the diet as it cannot be synthesised by the body.
10 classed as essential
- Arginine
- Histidine
- Iso-Leucine
- Leucine
- Lysine
- Methionine
- Phenylalanine
- Threonine
- Tryptophan
- Valine
List some:
water sources?
water losses?
- Sources:
- drinking
- feeding
- metabolic water
- Losses:
- urine
- faeces
- sweat
- insensible; no solutes (skin, respiratory tract)
What range of % is the animals body made of water?
50 - 80%
Which is the most critical nutrient?
WATER
*Describe measures of water quality
How do we assess water quality?
- Odour and taste (organoleptic properties)
- bad smell = high microbial popn
- pH, salinity, TDS/TSS (total solutes in solution), TDO and hardness (physiochemical properties
- Organic chemical contaminants, heavy metals, toxic materials
- Excess minerals, nitrates, sulfates
- Bacteria
- coliform in faeces
**_\*Describe measures of water quality_** Describe TSS (ppm) levels and their suitability
- TSS = TOTAL SOLUTES in SOLUTION
- <1000
- no risk to stock
- 1000 - 3000
- mild diarrhoea possible
- 3000 - 5000
- temporary refusal possible
- 5000 - 10,000
- avoid using for breeding, poultry, young stock
- 10,000 - 15,000
- okay for mature dry sheep/cattle
- Greater than 15,000 mg/L TSS or > 600mg/L Mg = unsuitable for stock
Are proteins essential? Why?
What is their function?
- Yes, essential. Must be provided in diet as true protein or NPN
- Major constituents of all living tissue
- Can be made but deplete quickly
Describe protein structure
- Chains of amino acids
- Physical properties determined by sequence and type of aa present, presence of non-aa groups
- Aa’s all contain N, have amino group, carboxylic acid group and side chain
Amino acid groups:
name characteristics of:
Non-polar =
Polar =
Acidic =
Basic =
??
- Non-polar = hydrophobic
- Polar = hydrophilic (non-charged)
- Acidic = -vely charged
- Basic = +vely charged
What are the two types of protein classes?
- Simple (only amino acids)
- Conjugated (contain non protein groups)
Describe simple proteins
- only aa
- Fibrous (resisitant to digestive enzymes). Structural roke e.g. collagens
- Globular (compact, folded polypep. chains) e.g. albumins (milk, blood, eggs, plants)
Describe conjugated proteins
- Glycoproteins (contain heteroglycans)
- Lipoproteins (contain lipids)
- Phosphoproteins (contain phosphoric acid)
- e.g. casein; rumen protected protein
- Chromoproteins (contain pigments) e.g. haemoglobin
Describe some examples of Non Protein Nitrogen (NPN)
- Nucleic acids
- building blocks of all living organisms
- contain purines, pyrimidines, a pentose, phoshoric acid
- Amines
- involved in DNA, RNA, protein synth, cell signalling, can be toxic
- Amides
- urea and uric acid
- Nitrates (N3)
- can be reduced to nitrite (N2) in rumen -highly toxic
- Alkaloids
_*Describe the process of protein digestion and absorption in monogastrics and ruminants_
Monogastrics.
Protein digestion mainly occurs where?
Describe Liebig’s law of minimum (limiting amino acid)
- digestion of proteins occurs in sml intestine
- Growth is controlled not by total amount of resoirces available but by scarcest resource (Liebigs law)
- deficient in 1 aa effects production of others
- most important aa in diet is one w/ least []
- Limiting amino acid is any aa not present in sufficient amounts to enable protein synthesis to proceed
_*Describe the process of protein digestion and absorption in monogastrics and ruminants_
Monogastric diagram
Draw as much as you can, describe as much as you can
*Describe the process of protein digestion and absorption in monogastrics and ruminants
List ruminant protein sources
_*Describe the process of protein digestion and absorption in monogastrics and ruminants_
Describe microbial protein production
- most dietary protein degraded in rumen
- MP reaches abomasum & SI when microbes washed out of rumen
- Optimal digestive efficiency occurs when growth rate of microbial mass is maximal
- Need rapidly growing microbe popn
- dependent on nutrient supply
*Describe the process of protein digestion and absorption in monogastrics and ruminants
Describe the synthesis of microbial protein from NPN
- If sufficient energy, microbes can synthesise protein from NH3
- NH3 converted into urea in liver (recycling process; MNG do not do this they excrete via kidneys)
- Recycling in saliva or returned to rumen as NPN source
