feed mixing and storage october 10, 2012. factors that influence stored feed moisture heat pests
TRANSCRIPT
Feed Mixing and Storage
October 10, 2012
Factors that Influence Stored Feed
• Moisture • Heat• Pests
Desired Moisture(when stored in aerobic conditions)
• Whole grains should contain less than 13% moisture.– Shelled corn can go up to 15.5%
• Ground and/or rolled grains should contain < 11%.
• Baled forages should be cured to contain 18-20% before being stored.
Facilitating Safe Moisture Storage
• Artificial drying – Disadvantage: can be expensive due to energy
costs• Field drying – crop remains in the field longer
– Disadvantage: weather losses/damage, predators, harvest loss, time in field
• Proper ensiling
Too much moisture
• Bacteria growth• Mold growth• Fungi growth
– Reduce palatability, alter nutrients, and produce toxins
• Fermentation and heat = browning • Spoilage and nutrient destruction• Issues with caking• Spontaneous combustion risks
Pest Infestations• More common issue for grains rather than
forages. • Insects or rodents
• Damage may be grain destruction or contamination. • Feces and urine contamination 10 x more
than grain destruction or consumption• Reduce palatability• Increase risk of disease
Reducing Pest Issues• Store feed in rodent proof containers• Don’t store against the wall. Leave space. Off floor.
– USDA inspection issue• Empty and clean bins when not used. • Clean up spills. • Keep feed rotated – first in first out. • Get a rat terrier!!!
Mixing Feeds
• Most important thing is accurate formulations and proper weighing.
• Scales must be adequate and appropriate. • Scales should be maintained and kept clean, calibrated
on a regular schedule. • Conversions are a must-have skill.
– % to grams per ton, Lb to Kg, g to Lb, oz to grams• 16 oz per Lb• 453.6 grams per Lb• 1000 grams per Kg• 1 mg/kg = 1 ppm
Types of Feed Mixers
• Two major types– Batch Feed Mixers– Continuous Flow Mixers
Batch Feed Mixers
• Types– Vertical– Horizontal– Auger wagon
Mixers
• Comparing horizontal with vertical mixers: • Better for molasses and liquid ingredients.• Handle silage and ground hays better. • More expensive. • Require less mixing time. • Typically higher energy cost
Batch Mixers
• Stationary– Advantages: High accuracy, flexibility for mixing– Disadvantages: Feed needs transported to mixer,
storage, labor and energy costs • Portable
– Advantages: Convenient to producer, ease of transport, uses existing tractors for power, fenceline feeding, freshly mixed
– Disadvantages: Equipment tied up, labor and time, start up costs (renting or purchasing)
Continuous Flow Mixers
• Ingredients are simultaneously measured, ground and mixed.
• Advantages: automated, little space needed, accurate, may be more ideal for smaller situations and batch sizes.
• Disadvantages: No roughage, storage costs, energy costs, transporting costs associated with ingredients and finished mixes.
Mixing of Feeds• Order of ingredients added is EXTREMELY
important to the final mix. – Typical corn/SBM diets
• About 25% corn should be added first to “charge” the mixer.
• Followed by vitamin/mineral premix, additives, protein supplements.
• Followed by remaining grain. • Liquids should not be added at the very end but after
the critical additives (approximatley 60 – 70% of the mixing time)
Factors Affecting Mixing Efficiency
• Type of mixer chosen• Sequence of ingredients• Filling of mixer• Length of mixing time• Ingredient particle size• Ingredient density• Proper clean out
– Flushing with ground grain after mixing a batch
Interpreting Mixer Tests
• Assay for salt in multiple locations within the mix to determine the mean & standard deviation.
• Determine coefficient of variation (CV):– %CV = SD/mean x 100– < 10% CV is Excellent mixing– 10 – 15% CV = Good = increase mixing time by 25 – 30%– 15 – 20% CV = increase mixing time by 50%– > 20% CV = may need to re-evaluate other factors
ExampleLocation Salt (%)
1 0.24
2 0.51
3 0.55
4 0.42
5 0.59
6 0.55
7 0.59
8 0.59
9 0.64
10 0.55
Mean = 0.523Standard Deviation = 0.1156CV = (0.1156/0.523) x 100 = 22.10%
What would you do with this mix?
References• PDF Articles on Mixing
– Testing Mixer Performance – K State Extension– Sequencing of Feed Ingredients for Mixing – South
Dakota State University– Residue Avoidance Program – ISU Extension
• Book– Processing Feeds = pages 265-271– Mixing and Storage = pages 271 – 275– Laws and labeling (including collective terms) = pages
305 - 316
GA Requirements for Labeling