Lecture 8 - Food and Feed Flashcards
The components of the diets
Feedstuff
All feedstuff offered during a 24 hours period
Ration/Daily ration
Nutrients that must be provided in the diet to support health
Essential nutrients
Feed formulated to provide all essential nutrients for the animal (except water); can be fed as a sole food source (such as extruded diets for dogs and cats that are balanced)
Complete feed
True or False: Most livestock diets are a mixture of individual feedstuff, although complete feeds do exist as an option
True
High fiber foods with a crude fiber content of 20% or more; examples include forage, straw, silage/haylage, and seed hulls
Roughage
Starches, simple sugars, proteins, vitamins, and minerals are found in the plant cell’s ________.
Cytosol
Fiber comprises the cell _____, and soluble fiber is in the _____________ space, forming a matrix that holds cells together.
Wall; intercellular
Seeds (grains) have a high content of…
Starch
Cellulose, hemicellulose, and lignin are all examples of fiber found in the… (name the part of the cell)
Cell wall
Pectin and gums are both examples of fiber found in the… (name the part of the cell)
Intercellular space
Fiber and starch are both polysaccharides, but what is the key factor that makes them different in regards to dietary needs?
Endogenous mammalian enzymes cannot break the 1, 4 glycosidic linkage (only alpha) in cellulose or hemicellulose
What eventually happens to starches with bacterial fermentation?
They form volatile fatty acids (VFA)
Carbohydrates that do not support the building foundations of the plant, and thus are usually more digestible
Non-structural carbohydrate (NSC)
These represent a fraction of the non-structural carbohydrates, and they are reduced when hay is soaked in water
Water-soluble carbohydrates (WSC)
Beet pulp is energy dense and has a ____ NSC content, while rice bran is energy dense but has a _______ NSC content
Low; Higher
Extra note:
Low = 4 to 20% NSC DM
Higher = 16 to 34% NSC DM
Where does fermentation occur in horses, rabbits, and rodents?
Hindgut
Where does fermentation occur in camelids and ruminants?
Forestomach
An anaerobic process where the substrate is broken down to simpler compounds by microbial enzymes (such as cellulase)
Fermentation
What is produced during fermentation?
Energy, VFAs, and gasses (CO2 and CH4)
A non-carbohydrate carbon polymer found in plants; its content increases in plants as they mature and grow, and digestibility decreases when it exists in high amounts
Lignin
What structural component in lignin molecules directly correlates with combustibility?
They are high in hydrocarbons
Grass and legumes are both examples of ___________.
Forage
What is the link between legumes and nitrogen?
Associated bacteria can fix N2 into the soil, then NH3 is absorbed into the plant to be used as substrate for protein and other nitrogenous compounds
Refers to plants that are available for grazing; can either be cultivated or wild and may or may not be irrigated
Pasture
Cut forage that is dried and consists of 90% dry matter and 10% moisture; can be stored for relatively long periods of time in bales and stacks once cuts
Hay
Most hays are either __________ or __________ hay
Grasses (ex: timothy grass hay, orchard grass hay)
Legume (ex: alfalfa hay)
What are the stages of maturity for hay?
(4 stages)
- Bud stage (HIGHEST nutrient content)
- Bloom stage (high yield, decreased digestibility)
- Seed production stage (aged, less digestible/nutritious)
- Dormant stage (LEAST digestible/nutritious, often burnt for fertilizer rather than used for graze)
First harvest, variable maturity, less digestible, and lower nutritional value
First cutting of hay
Uniform growth, greater water penetration, warmer weather, higher nutritional value, higher digestibility
Second and third cutting of hay
How can water exposure affect hay?
(2 answers)
- “Moldy basement smell” (hay too wet when baled or got wet while in storage)
- Dark brown color, visible mold spores (water damage)
What factors should be noted when evaluating hay?
(3 factors, one word each)
Appearance, color, and smell
What is the MOST ACCURATE way to determine if hay is of good quality?
Lab analysis of nutrient content and digestibility from a core sample
The forage that regrows after hay is cut, dried, and removed; high quality, nutrient rich, and lush
Aftermath - also called stubble (mostly for grains) or residue
Bloat, enterotoxemia, laminitis, pulmonary edema (cattle) are all clinical signs that may arise as a result of ingesting hay that is too _______.
Rich
Stems of mature grain plants left behind once grains are removed; thick and high in lignin; better as substrate than food, but can be chopped into small pieces and added to livestock ration as a partially digestible fiber
Straw
Cereal crop that is chopped and fermented prior to being fed; usually uses the entire plant (stems, leaves, and grain); 65 to 70% moisture, and 30 to 35% dry matter
Silage
Made from a non-grain forage such as alfalfa; usually uses the entire plant; 40 to 50% moisture
Haylage
What are the steps of ensiling (the process of silage and haylage production)?
- Crops are cut and removed from field
- Material is packed tight and sealed in a silo or bag to ferment (anaerobic process, lack of O2 vital to process)
- Acid acts as preservative and inhibits bacterial growth
A seed of bacteria from another silage used to expedite fermentation and limit mold and spoilage in new silage
Inoculants
Why is it important for silage to be packed in tightly to its storage space and under anaerobic conditions?
Mold and spoilage often occur in looser areas/gaps where air/rain/groundwater can penetrate
Oils/fats as well as grains/concentrates are ______ energy feeds.
High
True or False: Non-nitrogen proteins are useful in monogastric and hindgut fermenters, but not foregut fermenters
False; useful in FOREGUT fermenters but not monogastric or hindgut fermenters
Nitrogen-containing feedstuffs include not only protein, but also compounds such as…
Urea, biuret, and ammoniated forages
Where is non-protein nitrogen absorbed in species other the foregut fermenters?
Small intestines (later excreted in urine)
