Forage utilization and voluntary feed intake Flashcards
What is voluntary intake when it comes to nutrient intake?
The amount of feed consumed by an animal when access to feed is unrestricted. Aka ad libitum intake.
What is restricted intake?
The amount of feed consumed by an animal when the feed is restricted.
What is pasture forage intake?
A modified expression of voluntary intake, influenced by forage harvestability, environmental stress, and management.
What are the two things a producer must be familiar with to manage pasture land?
- The amount of dry forage produced by the pasture.
- The amount of forage required by each animal and the herd as a whole.
What is pasture carrying capacity?
The number of animals a pasture can support without harming the pasture and without reducing animal production.
What are the three ways to calculate pasture carrying capacity?
- Pasture clippings
- Average long-term forage yields
- Experience
What is stocking density?
The number of animals stocked per acre in a grazing unit at a particular time.
# of animals/ acre
50 animals/10 acre = 5animals/acre
What is stocking rate?
Number of animals on a pasture during a month or grazing season.
What happens if the stocking rate is too high or too low?
Too high = overgrazing
Too low = inefficient use of pasture
What are the three things that can be increased by forage production?
- Species selection
- Fertility
- Grazing management
What are the three factors that affect feed intake?
- Animal factors
- Forage factors
- Management factors
How does the physiological stare change before and after parturition (giving birth)?
Dry matter intake decreases before parturition and then increases after parturition.
What are the three animal factors affecting energy demand?
- Level of production
- Body size
- Physical activity
By how much percentage does abdominal fat restrict feed intake by?
3-30%
From dairy cattle and beef cattle, which cattle have higher maintenance and intake costs?
Dairy cattle
Is production higher for dairy cattle or beef cattle? Why?
Dairy cattle because they have higher gut capacity.
What is residual feed intake (RFI) a measure of?
Feed efficiency
How heritable is residual feed intake?
Moderately heritable
What is residual feed intake?
It is the difference between an animal’s actual feed intake and its expected feed intake based on it’s size and growth.
How much more does it cost to raise free-range animals compared to animals raised in a pen?
It costs 20 - 50% more to raise free-range animals because these animals expend more energy that animals in a barn.
What is the difference between native grazers and domesticated species when it comes to metabolism during the winter?
Native species have lower metabolic rates, therefore, require lower energy during winter.
Domesticated species have higher metabolic rates and require more energy during winter.
What is the general trend of ruminant species intake and %body weight in winter and spring?
It is higher in spring and lower in winter.
What are some forage factors that result in physical constraints?
- Low dry matter digestibility.
- Limiting nutrient
- Low forage dry matter content
- Long particle size
What are the effects of digestibility on dry matter intake?
As Digestibility increases so does dry matter intake.
