L9 Feed Additives

Question 1

What is feed additives

Answer 1

Compounds that are added to diets for reasons other than to supply nutrients

Question 2

What are purposes of feed additives?

Answer 2

improve feed efficiency
promote faster gains
improve animal health
increase production of animal products

Question 3

Feed additives that influence feed stability, manufacturing and properties of feed.

Answer 3

antifungal
antioxidants
pellet binder

Question 4

Additives that modify animal growth, feed efficiency, metabolism and performance.

Answer 4

feed flavour
digestion modifiers (enzymes, probiotics, buffers)
metabolism modifiers (hormones)
growth performance (antibiotics)

Question 5

Additives that modify animal health.

Answer 5

Drugs
- treatment and prevention of disease and internal parasites
- worming agents (phenothiazine, dichlorovos, piperizine)
- coccidiostats (monesin, amprolium, sulfaquinoxalene)

Question 6

Additives that modify consumer acceptance.

Answer 6

Xanthophylls
- important in poultry and fish nutrition
- Alfalfa (200mg/kg)
- Yellow corn (20mg/kg)
- Marigold petal meal (6000-10000mg/kg)
- 1-3% alfalfa meal

Question 8

Antifungal feed additives.

Answer 8

• prevent fungal growth
• moisture content 13-14%
• humidity 80-85%
• temperature 55F
• propionic acid (1% in diet) can last for 90 days
• sulfur dioxide

Question 9

Antioxidants

Answer 9

• prevent autooxidation of fats
• Natural (Vita E&C)
• Synthetic (ethoxyquin & butylated hydroxytoluene BHT)
• 62.5-125 ppm of ethoxyquin in broiler diets

Question 10

Pellet binders

Answer 10

• give firmer, stronger pellets with reduced tendency to crumble
• bentonites (2-3%) - improve utilisation of urea by ruminants by absorbing mycotoxins
• ball clay (3-4 ppt in poultry and fish diet)

Question 11

Feed flavor

Answer 11

• increase the acceptance of diets with low palatability
• increase the intake of palatable
• increase the intake of diets during period of stress
• sucrose
• saccharin

Question 12

Enzymes

Answer 12

• digestion of substance that animal cannot digest
• cellulase enzyme
• B-glucanase (increase the digestion of B-glucans in barley and oats)
• Trichoderma viride (reduce viscosity of rye and improve utilisation by poultry)

Question 13

Buffers

Answer 13

• resist pH change
• for ruminants fed high-concentrate diets
• sodium bicarbonate (increase dry matter digestibility in beef cattle)

Question 14

Probiotics

Answer 14

• improve GI microbial balance
  Bacterial probiotics
• Lactobacillus acidophilus, Streptococcus faecium, Bacillus subtilis
• control pathogen like E.coli and vibrio cholera to not produce disease
  Yeast probiotics
• Saccharomyces cerevisiae, Aspergillus oryza
• reduce stress of calves when handling and shipping
• improve digestibility

Question 15

Hormones

Answer 15

Diethystilbesterol (DES)
- synthetic estrogen
- improve growth and feed efficiency in ruminants
Melengestrol acetate (MAG)
- synthetic progesterone
- improve weight gain and feed efficiency

Question 16

Antibiotics

Answer 16

• natural metabolites of fungi that inhibit the growth of bacteria
• treat diseases caused by bacteria
• added to food to enhance the rate of growth
• reduce stressed
• pig and poultry foods
• 20-40mg/kg improve 4-16% of growth rate and 2-7% in FCR
• Tetracyline, Bacitracin, Streptomycin, Virginiamycin, Flavomycin.