1. HARVESTED FORAGES Silagepp

2. ENSILING What is ensiling?
Storing a forage or grain crop at a relatively high moisture concentration in anerobic conditions to have it undergo fermentation to lactic acid.
Lactic acid will preserve silage as long as the silage isn’t exposed to oxygen

3. WHY ENSILE?

4. ENSILING Goals Avoid Decrease pH of ensiled crop to <4
Increase lactic acid concentration of ensiled crop to >4% of DM
Requires anerobic conditions
Avoid
Molding and heating of crop
Occurs if forage is exposed to oxygen
Forage DM% > 60%
Butyric acid production, protein degradation, and seepage from silage
Forage DM% < 30%
Dependent of forage species

5. APPROPRIATE MATURITY AND DM PERCENTAGE FOR ENSILING
Desired for ensiling
Crop
Maturity
DM%
Whole plant corn
50% milk line stage on grain
30-40%
Grain or forage sorghum
Medium dough stage of grain
Small grains
Late boot stage
35-45%
Grasses
Boot stage
40-50%
Requires wilting
Legumes
Late bud stage
40-50% Requires wilting

6. THE ENSILING PROCESS

7. THE ENSILING PROCESS Aerobic phase Organisms Nutrient Metabolism
Plant enzymes
Aerobic bacteria and yeasts
Nutrient Metabolism
Sugars oxidized to CO2
Changes in forage
O2 is consumed and CO2 produced
Temperature increases to 115oF
Sugars decreased
Length of change
Desire < 24 hours
Extended by:
Too dry
Long chop length
Slow filling
Poor packing
No cover
In extended, results in:
Excessive heating
Increased ADIN

8. Heterofermentative phase
Organisms
Heterofermentative lactic acid bacteria
Nutrient Metabolism
Sugars fermented to acetic acid, lactic acid, and CO2
Changes in forage
Increased concentration of acetic acid and lactic acid
pH decreased to 5.0
Sugars decreased
Length of change
Desire < 1 week
Extended by:
Forage being too wet
If pH never drops to 5
Causes
Forage too wet
Inadequate sugars
Results
Clostridium bacteria growth
Butyric acid production
Protein degradation to NH3 and other forms of NPN

9. Homofermentative phase
Organisms
Homofermentative lactic acid bacteria
Nutrient Metabolism
Sugars fermented to lactic acid
Changes in forage
Increased concentration of lactic acid
6 to 8% of DM
pH decreased to 3.8 to 4.2
Sugars decreased
Length of change
Desire < 2 weeks

10. Storage phase If not exposed to oxygen If exposed to oxygen
Forage well-preserved with little change in composition
If exposed to oxygen
Growth of aerobic bacteria and mold
Results in heating, nutrient loss, and decreased palatability
Growth of listeria bacteria
Results in listeriosis
Encephalitis
Metritis and abortion

11. Feedout phase Exposes silage to oxygen
Growth of aerobic bacteria and molds
Results:
Heating
Loss of lactic acid
Nutrient loss
Losses minimized by adequate feedout rate
Match diameter of tower silos or width of bunker silos to herd size
Season
Silo type
Winter
Summer
Inches removed/day
Tower 2 4
Bunker 6

12. SILO TYPES Tower Bunker or trench Silo bags 30 to 50% DM Easy to pack
Good for hay crop or corn silage
Minimal exposed surface
Expensive
Bunker or trench
30 to 40% DM
Difficult to pack
Not desirable for hay crop silage
Requires polyethylene cover
Considerable surface area at feeding
Less expensive than towers
Silo bags
Versatile
Bags subject to punctures and tears
Relatively low capital investment

13. Big bale silage Limitations 40 to 60% DM Advantages Inexpensive
Allows small amounts of forage ensiled
Transportable
No specialized equipment beyond wrapper
Limitations
Some large balers can not bale high moisture forage
Long forage more difficult to ensile than chopped forage
Bales are heavy
Plastic wrap subject to puncture and tears
Disposal of plastic

14. DM LOSSES FROM DIFFERENT SILO TYPES
Concrete tower
Bunker
Bag
Round bale
DM losses, %
Respiration 4
Harvesting 2
Storage 9 15 7 18
Feedout
Total 17 25 30

15. PROPERTIES OF HIGH QUALITY SILAGE
Silage pH
3.6 – 4.2
Lactic acid
4-8% of DM
Acetic acid
<2%
Butyric acid
<0.1%
Nitrogen fractions
Ammonia nitrogen
<5% of total N
ADIN
<12% of total N
Microbial assay
Total aerobic bacteria
<100,000 cfu/gm silage
Molds

16. MAKING HIGH QUALITY SILAGE
Harvest at appropriate maturity and moisture
Set chop length
Fill silo as rapidly as possible
Pack, pack and pack some more
Cover silos immediately
6-mil plastic
Weight on bunker silos
Feedout
Adequate rate
Maintain clean face
Crop
Length of chop
Hay crop ¼”
Unprocessed corn silage
3/8 to ½”
Processed corn silage
(Kernel processor) ¾”

17. SILAGE ADDITIVES Water Bacterial inoculants Enzymes
Added if forage moisture is inadequate
Requires 5 gallons/ton to change DM by 1%
Bacterial inoculants
Lactobacilli
Add a minimum of 100,000 cfu/gm fresh forage
Useful to:
Improve lactic acid production if forage is harvested at excessive moisture concentration
Prevent aerobic damage at feedout or in feed bunk
Enzymes
Cellulases, hemicellulases, amylases, pectinases
Increase sugars to improve lactic acid production
No consistent improvement

18. NPN sources Acids Sugar sources
Used with corn, sorghum, and cereal silages
Types
Anhydrous ammonia at 5 to 10 lb/ton fresh forage
Urea at 10 to 20 lb/ton fresh forage
Advantages
Increases crude protein content
Increases aerobic stability at feedout
Acids
Propionic or formic acid
Application: 10 to 20 lb/ton fresh forage
Applied to forage that is either too wet or too dry
Formic acid causes a rapid decrease in pH if too wet
Propionic acid inhibits mold growth in too dry
Sugar sources
Molasses, whey, or grain
Added to crops with low concentration of soluble sugars
Grasses and legumes
Increases lactic acid concentration
Loss of energy from the source

19. NUTRITIONAL VALUE OF HIGH QUALITY SILAGE
Lower feed consumption than fresh crop or hay
Lower NDF, but comparable ADF to fresh crop or hay
Comparable net energy concentration to fresh crop or hay
Comparable crude protein concentration to fresh crop, but greater than hay
Greater proportion of crude protein will be degradable in the rumen than fresh crop or hay
Higher carotene content than hay