Pasture Management Flashcards
What is the most important factor affecting CHO concentrations?
Growth stage
What are the two types of CHO?
Structural and non-structural (Storage)
What is 90% of structural CHO comprised of?
Cellulose, hemicellulose, pectin
How does cellulose change with age?
Increases with age
Which linkages cannot be broken down by a non-ruminant gut?
Beta 1-4 linkages
Which structural CHO is highly degradable?
Pectin
What molecule is part of cell structure but is not CHO?
Lignin, very resistant to degradation, alkali is used to break down lignin bonds
How does the digestibility of structural CHO and non-CHO change change with age?
Digestibility decreases with age because structural components increase with age
Which two components make up the non-structural CHO?
Fructan and starch
Which non-structural CHO can cause pasture-induced laminitis?
Fructan, dissolves in water
Which fiber contains more fructan: Ryegrass or Timothy Hay?
Ryegrass (Lower polymerization than Timothy)
Is amylose or amylopectin resistant to amylase activity?
Amylose
What percentage of most plants is amylose (Except peas)?
About 20%
Which non-structural CHO can cause normal laminitis?
Starch
Which has the least amount of starch and which has the most amount of fructan: Meadow fescue, cocksfoot, perennial ryegrass, Timothy
Least: Timothy
Most: Perennial ryegrass
Which part of a pant has the highest fructan content?
Stem (As opposed to leaves)
What time of day is non-structural carbohydrate concentration at its highest?
Mid/late afternoon to early evening (Also when you want to mow to get rid of parts with most sugar)
How does temperature affect the amount of non-structural carbohydrate in a plant?
Increased temperature = decreased NSC
How does light affect the amount of non-structural carbohydrate in a plant?
Increased light = increased NSC
How does water affect the amount of non-structural carbohydrate in a plant?
Decreased water = increased NSC
What percentage does grass contribute to the large animal diet?
80-90%, 60-65% in dairy cattle because they are so high producing
What is the main difference between permanent pasture and leys?
Permanent pastures are more than 5 years old, leys are less than 5 years old
Name some pros and cons about clover.
Pro: Restores nitrogen to soil, higher in many nutrients in comparison to grasses
Cons: May cause frothy bloat (Due to high protein), phytoestrogens mess with estrogen cycles of livestock
What problems does lucerne cause that are similar to those of clover?
Frothy bloat, phytoestrogens
What level is optimum for digestibility value?
At or above 75
Are magnesium and phosphorus constant throughout the growing season?
No, vary throughout season
Which has more protein between these pairs: Leaves and stems, legumes and grasses
Leaves > stems
Legumes > grasses
Which plant has the longest growing season, the fastest development/establishment, and is highly competitive?
Ryegrass
How do K and Mg interact in a fertilizer?
K prevents uptake of Mg, causes hypomagnesemia
What is the most important element in fertilizer?
Nitrogen
What organism frees nitrogen to be used in the soil?
Legumes
What general pH level is preferred by grasses?
Slightly acidic, 6-6.5 (Peat likes about 5.6)
What is added to basic soil to increase acidity?
Sulfur
What is added to acidic soil to increase basicity?
Lime (CaCo3 or MgCO3)
Name 5 types of grazing strategies.
Continuous, rotational (Often every 21 days), creep (Younger stock first and dams follow), mixed/alternate (Alternate species grazing on an area), zero (Cutting grass and bringing it in for indoor cows to eat)
How does integrated/conservation grazing work?
Let animals feed on 1/3 of field, cut other 2/3 for silage. Then move animals to recently cut 2/3 of field, let first 1/3 grow and then cut for silage. Then open all areas of the field for animals.
When should sward heights be the shortest and when should sward heights be the tallest?
Shortest in spring, tallest in autumn
