March 2018 Newsletter - #74
 
 
In This Issue
About Us
The Dairy One Forage Lab excels in providing high quality analyses  
and customer service. Our goal is to provide analytical services designed to meet the expanding demands of modern agriculture.  
New technology and traditional methods are combined to deliver fast, accurate results.
 
More than just CP, ADF, and aNDF
By Sarah E. Fessenden, PAS; Business Developer Manager


Recently I was asked to speak at a producer's meeting regarding some of the calculations that accompany your typical analysis. With nutrition conferences focusing heavily on the new things coming down the pipeline, I always find it refreshing to come back to our roots. Interpreting your analysis may seem too broad or too simple, but one of the most common conversations I had as a nutritionist was walking my customers through test results and devising a strategy to incorporate it into the diet. It was easy to fall back on two to four routine numbers. While traditional values such as CP, ADF, and aNDF are an important starting line, there are a number of calculated or predicted values that should also be assessed when evaluating forage quality or purchasing feed.

A value commonly used for comparison when purchasing forage is relative feed value, or RFV. RFV is calculated using ADF and aNDF. A more appropriately used measurement is relative feed quality, or RFQ. RFQ considers more of the forage components and is calculated using CP, fat, ADF, aNDF, NDFD48, TDN and NFC. You should consider replacing RFV with RFQ as your primary feed gauge as it includes digestibility, energy, and fiber. Below is an example of two hay samples with the same RFV but different RFQ due to digestibility.

 
% CP 
% ADF 
% NDF 
NDFD48 % NDF 
RFV 
RFQ 
Alfalfa A.
20 
30 
40 
45 
152 
151 
Alfalfa B.
20 
30 
40 
55 
152 
174 

Table 1. RFV vs RFQ alfalfa comparison


Net Energy (NE) and Total Digestible Nutrients (TDN) are occasionally still used by nutritionists to compare feeds. These energy values are calculated using CP, aNDF, fat, ash, lignin, ADICP, and NDICP. When available, In-vitro True Digestibility's(IVTD's) are substituted for aNDF and lignin to fine tune the contribution from fiber digestibility.

Non Fiber Carbohydrates (NFC) are calculated using CP, aNDF, fat, and ash. Though NFC may not typically jump to the top of your list when characterizing feed quality, it is still a very important part of the total diet being fed. Current recommendations for NFC are to formulate for 38-42% in the total diet ration for lactating cows.

While the values discussed above can be used when making purchasing decisions, they are also a helpful guide when assessing forage quality on your farm. Some farms have already been feeding 2017 forages, while others have not opened them up yet. In the November newsletter I elaborated on current trends for fresh corn silage samples and the implications for the coming forage year. Below is an updated chart on fresh silage samples. In both NY and PA there was an increase in fiber and a decrease in both fiber digestibility and starch. Starch digestibility in NY samples was unchanged, while samples from PA showed a decrease. If you desire summary data for a different state, please contact me directly and I'll be more than happy to summarize and supply that information.

 
Table 2. Fresh corn silage quality from
Sept 1st to Nov 25th, 2016 and 2017
 
Meet Savannah Dittmeyer!
Senior tech for Fibers


Savannah is originally from Dallas, Texas. She moved to NY to study Geology at Fredonia, before completing her AAS in Chemical Technology at Corning Community College in 2015. Using her geo-chemistry background, she started in the Agro-One Soils Lab in 2016 where she learned how to operate many different instruments. Her favorite was the ICAP Spectrometer which is used to determine the mineral content in the extracted soil samples. Savannah briefly returned to Texas for a short sabbatical, but she has since returned to work with Dairy One in the Forage Lab in 2017 as a Fibers Technician. In December 2017 she transitioned to Senior Technician for Fibers where she now has full operational oversight of that department.

"It's an exciting, fast-paced area to be in; there's always something interesting going on - exotic samples or experimental procedures."

Outside of work Savannah enjoys reading, playing drums or piano, and driving cross-country to see national parks and monuments. She also spends as much time as possible with her dog, Max. He has accompanied her on her cross-country treks and their favorite park so far has been Arches in Moab, Utah. 
Upcoming Events - Come see us!

April 4-5
Canadian Dairy Expo
Stratford, Ontario
 
April 10
Herd Health and Nutrition Conference
Syracuse, NY
https://prodairy.cals.cornell.edu/conferences/herd-health-nutrition

April 16-18
Tri-State Nutrition Conference
Fort Wayne, IN
  
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Dairy One - Forage Laboratory
730 Warren Road ~ Ithaca, NY ~ 14850
Phone:  1-800-344-2697 Ext. 9962