1.5 Feedstuffs - Proteins

Question 1

Even though we call them protein feeds or ingredients, conceptually, we need them for their…

Answer 1

Essential AA and amino nitrogen

ALSO! Provide other nutrients and energy

Question 2

Protein ingredients provide AA in diets to do what 6 things?

Answer 2

1. Maximize economic return
2. Optimize performance
3. Approach ideal protein/AA profile
4. For low protein diets, EAA:NEAA ratio
5. Use digestible/available AA
6. Minimize environmental impact

Question 3

How much of total dietary protein do cereal grains provide?

Answer 3

About 1/2
- Cereals have low CP, but they make up a large proportion of the diet
- AA pattern in any cereal grain is not ideal, so include high quality protein as well to complement cereal grain

Question 4

How much CP do ‘protein’ feeds contain?

Answer 4

More than ~20%
- plant sources
- animal products
- synthetic/crystalline AA

Question 5

The DE of protein feeds is similar to grains, but NE is lower, what does this effect?

Answer 5

1. Cost per unit energy greater than grains
2. Limit inclusion to needed level (for AA requirements)
3. Inclusion may be limited by properties of feedstuff (ex. ANF)

Question 6

Plants such as soybean are grown for human consumption. But what is a co-product of processing used in animal feed?

Answer 6

Oilseed meals (left after the oil has been extracted)
- CP content adjusted to a standard within a type by adding fiber (hulls) to reduce protein or removing fiber to increase protein

Question 7

What are 3 problems with oilseed meals?

Answer 7

1. often high fiber, low energy
2. often contain ANFs
3. potential for heat damage

Question 8

What is THE standard for price and protein quality?

Answer 8

Soybean meal
- Good AA balance
- >50% of all protein feedstuffs globally
- Highly palatable and digestible

Question 9

How does canola meal compare to soybean meal?

Answer 9

• Similar AA pattern
• AA less available, lower energy (especially NE) bc treated at a higher temp