By Mike Hutjens
The spring and summer forage growing season has challenged dairy managers across the United States:
• Drought conditions continue in the west and southwest.
• Excessive spring rains in the Midwest delayed planting corn silage and delayed harvesting first crop alfalfa.
• Nearly two million acres of alfalfa winter-killed in the Midwest.
These factors occurred after the huge drought stress of 2012, reducing forage inventories on dairy farms leading to high priced hay, corn, and protein supplement. Use the following checklist now when adjustment and strategies are still possible.
Checklist item #1. Current forage inventories are critical as fall forages (corn silage, last cutting of legume-forage, corn stalks, and fall cereal grains) can fill out forage needs. Your monthly inventory is needed to determine if you have adequate amounts to get to spring forages (winter cereal grain or first cutting or 2014 corn silage).
As a guide, 5 1/2 tons of forage dry matter (30 lb./day) is needed for large breed cows including dry and lactation phases (add 1.5 tons if heifers are going to fed forage from your inventory). These values include a 10% shrinkage loss.
Checklist item #2. If your inventory from checklist 1 is too low, decide on your strategy now, not in March when forage prices may be high and supplies limited.
• By-product feeds could be one alternative if implemented early.
• Cull low producing cow or cows with health challenges.
• Reduce heifers numbers and/or have heifers raised by someone else. But consider costs and heifer growth history on the commercial heifer raiser.
Checklist item #3. Monitor forage quality as large variation can be expected.
• First cutting may be low in quality (RFQ or relative forage quality index). Higher producing cows should be fed legume/grass forages over 150 RFQ. One alternative is using 2nd and later cuttings for the lactating cows and feed 1st crop to heifers or low-lactation cows.
• Corn silage will also vary as some corn was planted in July, which will not have starch. Pollination in Illinois was variable due to heat stress and low soil moisture levels in July. High-quality corn silage will be over 30% starch.
• Some corn silage will have to wait for a killing frost as immature corn can be over 80% moisture leading to poor fermentation and excessive leaching. Depending on storage system, dry matter needs to be over 30% (drier for conventional upright silos).
Checklist item #4. Be sure to preserve all forages grown on the farm or purchases. A research-based silage inoculant can reduce dry matter losses due to improper fermentation by 3% or more (that’s like getting three more acres of forage when harvesting 100 acres). Covering silage piles or bunkers with oxygen barrier plastic can reduce losses in the top 3’ leading to 3 to 5% conserved dry matter in the entire silage mass.
Baled hay should be stored inside or covered with a plastic tarp or bonnet to shed moisture (rain and/or snow). Bales must not be left on the ground as moisture will migrate into the bales. All bags should be inspected for holes due to rodents, birds, or other reasons and taped immediately.
Baleage should be wrapped in plastic the same day of baling at optimal dry matter 40 to 60% to achieve optimal fermentation and avoid molding.
Checklist item #5. If you are going to feed less alfalfa/legume forage and more corn silage, you will need to consider the following points.
• Long particles may be short leading to a need for more effective fiber (cud chewing and control rate of feed passage). Straw could fulfill this need. Using the Penn State Particle Separator (PSPS), have over 8 to 10% on the top box and over 40% in the second.
• Be sure kernel plant processors are adjusted correctly with 10 to 15% in the top PSPS box and over 50% in the second PSPS box with all kernels ground (no large pieces). Shredlage overcomes both of these risks.
• Legumes have higher natural buffering capacity related to its mineral profile. Buffers may be needed to control rumen pH over 5.9, especially in rations with corn silage providing over 50% of the forage dry matter and if the ration is wetter due to immature corn silage.
• Protein levels and forms (level of rumen degraded protein and soluble protein) will change. Monitor closely. Be sure your nutritionist adjusts protein fractions including metabolizable protein level and amino acid flow.
• Nutrient requirements do not change with less legume or more immature corn silage or cereal grain forage (triticale or wheat for example).
- September 2013