1.8 Fats and Oils

Question 1

Essential fatty acids

Answer 1

Linoleic acid
- precursor for arachidonic acid

Linolenic acid
- precursor for EPA and DHA (longer)

Question 2

What are the fxns of dietary fat?

Answer 2

1. carrier for fat-soluble vitamins
   - they absorb with dietary fat
2. reduces dust
   - palatability
   - animal and human health
3. manipulation of carcass fat
4. lubricate feed mill equipment

Question 3

What are 4 sources of feed-grade fats for animals?

Answer 3

1. Inedible (for humans) animal fats and vegetable oils
2. Tallow and lard
3. Marine and vegetable oil (both more expensive)
4. Restaurant grease

Question 4

What are 3 potential limitations of fats and oils in feed?

Answer 4

1. Cost
2. Rancidity (oxidation)
   - especially oils high in PUFA
3. FA composition
   - effect on pork quality

Question 5

Unsaturated fatty acids

Answer 5

• higher energy than saturated fatty acids
• more susceptible to oxidation
• vegetable oils usually high in UFA

Question 6

Saturated fatty acids

Answer 6

• usually animal origin
• solid at room temp
• dark color
• cheaper
• young animals may have difficulty digesting

Question 7

What does the carcass/tissue/products of chickens and pigs reflect?

Answer 7

Dietary fat
- carcass and egg GA profile can be manipulated

Question 8

What are the active forms of omega-3 in the body? What is the precursor?

Answer 8

EPA and DHA are active forms; precursor is linolenic acid
- chickens moderate at elongating/desaturating
- mammals are poor at elongating/desaturating

*can feed chickens flax oil, they elongate/desaturate, mammals eat the chicken (cheaper than fish oil)

Question 9

What are the 2 biological effects of fat?

Answer 9

1. Slows digesta passage rate
   - increased digestibility of other nutrients
2. Less HI than CHO
   - beneficial in hot climates to maintain animal energy intake

Question 10

When is pancreatic lipase maximized for pigs?

Answer 10

At 8 wks old
- SCFA more digestible than LCFA
- Unsaturated fat more digestible than saturated
= use a short-chain, unsaturated fat when feeding baby pigs