With everyone experiencing record low milk prices, which are not expected to change much for 2001, managing your feeding program is an area that will be very critical to controlling costs.
Controlling feed costs means feeding balanced rations, and balancing rations starts with forage sampling and analysis. I would like to share with you some forage sampling recommendations that Phil Taylor, dairy agent for Michigan State University Extension, presented in the Michigan Dairy Review.
Meaningful sample analysis starts with a good representative sample of what is being fed. Sampling should be done as a normal part of the process of feeding cows, not as a special activity requiring extra people at a special time. The most representative sample will be collected while the feeding operation is taking place.
The process by which the sample is taken is also important and changes with the types of forage and structure in which the forage is stored. Dry hay may not make up a large amount of rations today, however, sampling and analysis is still important. Use a core sampler (with an extension for round bales and big squares) take a composite sample from a minimum of 12 bales. Take samples as hay being fed changes.
Silage sampling takes a different approach for bunker silos and tower silos. Bunker silos may require less frequent sampling than an upright. A good rule of thumb is to sample every quarter of the silos length. So for a 100 foot bunker sample very 25 feet. More often if the silage makes a noticeable change (dry matter change, field change, etc.).
When sampling from a bunker silo the first rule is to sample what the cows are receiving. If spoilage and mold are removed don’t include this in the sample. If all this is mixed in, sample it that way.
An easy way to get the sample is to take a clean empty mixer, put in the amount of silage usually fed and mix for a short period of time. Dump out a small pile and take a gallon or more sample size.
Another method using a bucket loader as a mixing tool. Dump some silage in piles on a clean area and use the bucket to lift and dump and mix the pile. Again, take a gallon or more as a representative sample. You need several buckets of silage from across the face of the pile.
For tower silos sample the silage while the silo unloader is running. Sample several times and especially sample at the beginning as the silage will change after the very top is removed. Take a partial sample every 1 to 11/2 minutes of unloader operation. Composite all the samples for mixing.
Once you have all the composite samples it is time to do a final mixing for a representative sample to send to the lab. Taylor described the following tarp technique for the final mixing of the samples.
In an enclosed room, out of the wind, dump the samples on a tarp or heavy piece of plastic, about four feet square. Take one corner of the tarp and fold diagonally to the other corner. Unfold the tarp and continue with the other 3 corners. After all corners have been folded and unfolded, use your hand to carefully split the sample into four equal parts. Discard two opposing quadrants of the original sample and remix. Continue removing and mixing until the sample size is the right size to send to the lab.
Forage sampling and testing should be a standard operating procedure on every dairy farm. The type of forage test and what to test for I will leave for another column.
(The author is a dairy agent for OSU Extension in Wayne County. Questions or comments can be sent in care of Farm and Dairy, P.O. Box 38, Salem, OH 44460; or e-mail: firstname.lastname@example.org.)