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Consultant Link Fine Ground Corn Meal

How Important is Particle Size?
Particle size vs Feeding Value Table

Corn Meal Particle Size Testing Procedure

Dairy Tech Labs Corn Silage Overview
1999 vs 1998 Corn Silage Analysis

Liquid Supplements for Today's Dairy Enterprise
Summary of a presentation by Rick Lundquist, Ph.D.

HOW IMPORTANT IS PARTICLE SIZE?
By Dr. Larry Chase

There are plenty of cases involving poor animal performance when feeding coarsely ground corn versus finely ground corn products. Mills will vary in the fineness in which corn is ground. One method to evaluate the value of corn products is to measure the percentage of material remaining on a 1/16" screen. Below is a corn meal particle scoring chart.

Evaluating Corn Value Based On Coarseness
% Fines	Relative Value (%)
95+	110
90	105
75	100
55	90
15	75

Dairy Manager

CORN MEAL PARTICLE
SIZE TESTING PROCEDURE

Procedure:

• Weigh a 10 ounce sample of ground Corn
  
• Sift the sample (approx. 1/16 " screen) until all fine material has passed through the screen.
  
• Weigh out the particles remaining on the screen and compare the results to the table below.

Amount Remaining on Screen	Score
1 ounces	Excellent - Too Fine?
2 ounces	Excellent
3 ounces	Good
4 ounces	Fair
5 ounces	Poor
5+ ounces	"Turkey Feed"

* The above procedure will provide you with an estimated measurement of the efficiency of utilization of carbohydrates in the rumen. Finely ground corn can be used in forage feeding programs where rapidly fermented carbohydrate is desirable. For best results, consult your nutritionist for assistance with interpreting your results.

1999 vs 1998 Corn Silage analysis

1999 corn crop was very variable because of the effects of the drought. It will be very important to test samples frequently to monitor changes. Overall the results for analyses done in October and November 1998 versus 1999 are listed below.

	1999	1998
# of samples	917	954
Dry Matter	33.1	35.8
Crude protein	9.2	7.9
NE 1	.70	.70
NDF	46.9	47.3
Ca	.29	.24
P	.24	.24
K	1.16	.98
Mg	.2	.17

As you might expect silage is lower DM (farmers cut earlier, afraid they wouldn't get crop if waited, and fooled by brown leaves into thinking it was dry), higher CP, Ca, K, and Mg reflect higher proportional stalk and less cob. Energy is predicted to be the same, HOWEVER, this is based only on fiber, which is similar. It does not take into account higher digestibility.

Digestibility analysis
Pioneer Hybrid determines digestibility on its hybrids in test plots across the northeast. Their results are:

	1999	1998
# of samples	710	790
Dry Matter	37.4	37.0
Crude protein	7.9	6.6
NDF	41.7	43.1
Sugar	6.5	5.9
Starch	28.8	30.2
Whole plant dig.	71.3	70.1
Digestible Fiber, % NDF	47.3	46.4

Crude protein is up because of more stalk to ear, sugar is up because ear formation was spotty and starch is down because where poor ears formed sugars did not convert to starch in the kernel. NDF is down because of proportionally more sugar remaining in the stover. Digestibility of fiber and whole plant is up as expected in a dry year. Stalks are shorter and less lignified. (However, whole plant digestibility is lower than in 1997 when it was 74.9%).

Outside testing
There may be a limited number of situations where additional testing is justified. Some of these tests might be 1) Mycotoxins 2) Silage VFA's 3) Digestibility. These tests can be done at outside labs. Tests cost from ~ $50 to $150 per sample. Some of the potential problems with the tests are: Mycotoxin and VFA tests only identify what is in the sample - representative sampling is essential. Be sure the farmer is able and willing to do something about the bad forage if a problem is detected before going through the testing. There are several methods of digestibility testing which each give differing results. Be sure the farmer and you can interpret and use the results before testing. Having given the cautions we can arrange for these tests if appropriate and beneficial.

Summary
On average feeding value should be similar to slightly better than last year - IF FERMENTATION WAS GOOD. The variation in moisture when filling and the relatively higher sugar can result in more unusual fermentation and possibly poorer stability when feeding out. Use pH test strips to check fermentation where there is a question. If pH is unusual expect lower feeding value and potential for problems.

LIQUID SUPPLEMENTS FOR TODAY'S DAIRY ENTERPRISE
Rick Lundquist, Ph.D.
Lundquist & Associates


Historical:

• Smaller dairies usually include some molasses or molasses blends in a purchased complete grain mix from a feed company. The inclusion rate is typically 3 - 7% of the grain. The amount of molasses or molasses blend subsequently fed is limited to about 1 - 1.5 pounds per head per day.
• Molasses added at the mill reduces dust and prevents separation of the mix as well as enhancing palatability and nutritional content. However, flowability of the grain often limits the percentage of molasses that can be included in commercial grain mixes.

Today:

• As dairies expand in size and replace complete grain mixes with commodities, liquid feed usage will decline, unless it is added directly on the farm. Dairies that feed commodities may continue to purchase a concentrate with molasses or a molasses blend added at the feed mill, but these concentrates have low inclusion rates in the total mixed ration (TMR), so total molasses intake will be reduced if none is added on the farm.
• Liquid feeds are palatable, convenient vehicles for the delivery of many nutrients and additives used in the dairy industry. Manufacturers have the ability to combine many different ingredients in liquid feeds, allowing dairy producers to deliver supplemental minerals and vitamins, fat, urea, additives and various fermentation byproducts in one liquid supplement. Trace mineral and vitamin supplementation through liquid supplements is an efficient way to deliver these micro nutrients with sufficient carrier to insure thorough mixing.
• While the liquid feed manufacturer may have the ability to combine many different ingredients in one mix, I prefer to limit the number of ingredients. Flexibility may be sacrificed if too many ingredients are combined in the same supplement. The dairy producer needs to adjust rations quickly. Complicated liquid supplements can be cumbersome for both the dairy producer and manufacturer if changes are required frequently. To avoid this, I prefer to supplement only ingredients that remain relatively constant in the diet and may require adjustments only seasonally at most.
• Liquid feeds have very little shrink. This reduces potential waste of expensive additives included in small amounts in the diet through the liquid feeds. Expensive items of low inclusion rates don't end up at the bottom of the feed bunk as with many dry supplements.