Exam 1 Flashcards
What are the life requirements for plants?
- Water
- Energy- sunlight
- Nitrogen (Nitrate or NH3)
- Inorganic elements (Minerals)
What are the life requirements for animals/humans?
- Water
- Energy (CHO and Lipids)
- Nitrogen (in the form of essential amino acids)
- Inorganic elements (Minerals)
- Vitamins
- Essential fatty acids
What are the 6 major nutrient categories?
- Carbohydrates
- Fats (Lipids)
- Proteins
- Vitamins
- Minerals
- Water
What are Carbohydrates?
Simple Sugars (mono, di, poly) Fibrous polysaccharides
What are Lipids?
(Fats)
Triglycerides and Phospholipids
Essential fatty acids
Sterols (e.g., cholesterol)
What is a protein?
Essential and non-essential amino acids
Nucleic acids, urea etc.
What are the organic nutrients?
- Carbohydrates
- Lipids
- Proteins
- Vitamins
(all of which are carbon based)
What are some variables that impact feed nutritional values?
Genetics, geographic locale, weather, milling/storage
What are some variables that impact an animal’s nutrient requirements?
Age, Gestation/lactation, breed, stress
What are the 4 functions of water?
- Solvent
- Diluent
- Transport
- Substrate
What are the three sources of water?
- Drinking water
- Water with in food
- Metabolic water
Where does water absorption occur? Vs.
Where does most NET water absorption occur?
Absorption of water occurs throughout the GI track; lost of water added to food stuff in early sections of the GI track
Most NET water absorption occurs in the large intestines
How does water absorption occur?
By passive diffusion
What are the three key factors that affect water requirement/intake?
- Water availability
- Dry matter intake
- Water losses
What are the four common factors that affect suitability of water for livestock?
- Total dissolved solids (TDS)
- Sulfur and Sulfate (rotten eggs; frequent)
- Nitrates (linked to repro. problems in livestock)
- Iron (frequent)
What is the most essential nutrient?
Water
Gross Energy
Also referred to as?
What is GE measured with?
- The quantity of energy (in the form of heat) resulting from the complete oxidation of food, feed, or other substance.
- Also referred to as Heat Combustion
- GE is measured by a bomb calorimeter
Digestible Energy?
- Intake of food energy (GE) minus energy lost in feces
- Requires collection of feces
Metabolizable energy?
ME = GE of food consumed minus energy lost in feces, urine and combustible gases
Net energy
What is the equation to calculate NE?
Portion of energy that is available to the animal for maintenance or various productive purposes
(making milk, eggs, doing work)
NE = ME - HI;
Net Energy = Metabolic Energy - Heat Increment
What is Heat Increment?
Represents the heat produced by the digestion and metabolism of a food stuff over and above what is produced prior to food ingestion
**The more the nutrient is absorbed and deposited into tissues the lower the HI
Maintenance
How much Metabolizable Energy is needed for normal production to meet maintenance needs in Cattle?
Refers to (in context of animal nutrition) a condition in which a non-productive animal neither gains nor loses body energy reserves
65-70% of ME is needed for normal production to meet Maintenance needs
Maintenance Energy is used for?
used for blood circulation, kidney and liver functions, respiration, protein and lipid biosynthesis and turnover, ion transport ,etc.
Energy required for maintenance is mostly needed to produce what?
ATP
Gross Efficiency
Refers to the caloric value of the product over the caloric intake; (Calories Out over Calories In)
Net Efficiency
The caloric value of the product over caloric intake ABOVE maintenance
(Calories out) over (Calories in - Maintenance)
Indirect Calorimetry
The amount of energy in feedstuff can be determined INDIRECTLY by simply measuring oxygen consumption required in metabolizing food
This approach provides the physiological energy value of feedstuff
CHO : Protein : Fat, respectively?
4: 4:9
* *More energy is released from fats than from carbohydrates on a per gram basis
Energy is formed by?
The complete oxidation of carbons resulting in the formation of CO2 and metabolic water
What are the two critical factors of how we feed livestock and companion animals?
- Cost and quality of feedstuffs
2. GI tract physiology
Fermentation refers to?
Metabolization with out oxygen to create energy
What is the crop used for in Avians?
For storage only
birds will empty crop if scared in order to escape
What is the Proventriculus in Avians?
The true stomach
What is the gizzard used for?
Functions as teeth in birds (equivalent to mouth)
What is the Ceca?
2 cecums for fermentation
The environment of the rumen?
- Highly reduced (little O2)
- pH= 6.0 - 7.0
- 10 - 15% dry matter
- 39 degree C
What are the four compartments of the foregut?
- Rumen
- Reticulum
- Omasum
- Abomasum
What occurs int he rumen?
Most fermentation by bacteria, protozoa, and fungi takes place here;
Digestion via microbial enzymes
What is the function of the reticulum?
Primarily to move food back up into the mouth for additional chewing
(only partially separated from the much larger rumen)
“Reticular groove” allows milk to by-pass the rumen
What is involved in rumination?
- occurs 10 - 12 hours a day
- reduces particle size
- only small particles leave reticulo-rumen
- incr. surface area leading to more efficient microbial digestion
- breaks down plant coating
